Random access procedure with mobility

Abstract

A method may include receiving, by a wireless device, a first Physical Downlink Control Channel (PDCCH) command that initiates a first Random Access (RA) procedure for a candidate cell of a Layer 1 or Layer 2 triggered Mobility (LTM) procedure. The method may also include initializing a power ramp counter to a first value based on the first PDCCH command indicating an initial preamble transmission. The method may also include completing the first RA procedure after transmitting a first RA preamble via the candidate cell and for the first RA procedure using a first transmission power determined based on the first value. The method may additionally include receiving a second PDCCH command to initiate a second RA procedure for the candidate cell. The method may also include incrementing the power ramp counter from the first value to a second value in response to the second PDCCH command indicating a preamble retransmission.

Description

Cross-reference to applications related to mobile random access procedures

[0001] This application claims priority to U.S. Provisional Application No. 63 / 526,345, filed July 12, 2023, which is hereby incorporated by reference in its entirety.

[0002] Examples of several embodiments of the various embodiments of this disclosure are described herein with reference to the accompanying drawings.

[0003] Figures 1A and 1B illustrate example mobile communication networks in which embodiments of the present disclosure may be implemented.

[0004] Figures 2A and 2B show the New Radio (NR) user plane and control plane protocol stacks, respectively.

[0005] Figure 3 illustrates an example of the services provided between protocol layers in the NR user plane protocol stack of Figure 2A.

[0006] Figure 4A shows an example downlink data flow through the NR user plane protocol stack of Figure 2A.

[0007] Figure 4B shows an example format of the MAC subheader in a MAC PDU.

[0008] Figures 5A and 5B show the mapping between logical channels, transport channels, and physical channels used for downlink and uplink, respectively.

[0009] Figure 6 is an example diagram showing the RRC state transition of the UE.

[0010] Figure 7 shows an example configuration in which OFDM symbols are grouped into NR frames.

[0011] Figure 8 shows an example configuration of time slots in the time and frequency domains of an NR carrier.

[0012] Figure 9 shows an example of bandwidth adaptation using three configured BWPs with NR carriers.

[0013] Figure 10A shows three carrier aggregation configurations with two component carriers.

[0014] Figure 10B shows an example of how aggregated cells can be configured into one or more PUCCH groups.

[0015] Figure 11A shows an example of the SS / PBCH block structure and location.

[0016] Figure 11B shows an example of CSI-RS mapped in the time and frequency domains.

[0017] Figures 12A and 12B show examples of three downlink and uplink beam management procedures, respectively.

[0018] Figures 13A, 13B, and 13C illustrate a four-step contention-based random access procedure, a two-step contention-free random access procedure, and another two-step random access procedure, respectively.

[0019] Figure 14A shows an example of the CORESET configuration for the bandwidth portion.

[0020] Figure 14B shows an example of CCE-to-REG mapping for DCI transmission on CORESET and PDCCH processing.

[0021] Figure 15 shows an example of a wireless device communicating with a base station.

[0022] Figures 16A, 16B, 16C, and 16D show example structures for uplink and downlink transmissions.

[0023] Figure 17 shows an example timing diagram of one aspect of an embodiment according to the present disclosure.

[0024] Figure 18 shows an example timing diagram of an RA procedure according to an embodiment of the present disclosure.

[0025] Figure 19 shows an example flowchart of an embodiment according to the present disclosure.

[0026] Figure 20 shows an example flowchart of an embodiment according to the present disclosure.

[0027] Figure 21 shows an example flowchart of an embodiment according to the present disclosure.

[0028] Figure 22 shows an example timing diagram of one aspect of an embodiment according to the present disclosure.

[0029] Figure 23 shows an example timing diagram of one aspect of an embodiment according to the present disclosure.

[0030] Figure 24 shows an example timing diagram of one aspect of an embodiment according to the present disclosure.

[0031] Figure 25A illustrates an example timing diagram of receiving a control command according to an embodiment of the present disclosure.

[0032] Figure 25B illustrates an example timing diagram of receiving a control command according to an embodiment of the present disclosure.

[0033] Figure 26 shows an example timing diagram of one aspect of an embodiment according to the present disclosure.

[0034] Figure 27 shows an example timing diagram of one aspect of an embodiment according to the present disclosure.

[0035] Figure 28 shows an example flowchart of an embodiment according to the present disclosure.

[0036] Figure 29 shows an example flowchart of an embodiment according to the present disclosure.

[0037] Figure 30 shows an example timing diagram of one aspect of an embodiment according to the present disclosure.

[0038] Figure 31 shows an example timing diagram of an LTM program according to an embodiment of the present disclosure.

[0039] Figure 32 illustrates an example diagram of one or more candidate / target (LTM cell) configurations according to an embodiment of the present disclosure.

[0040] Figure 33 shows an example flowchart of an LTM procedure according to an embodiment of the present disclosure.

[0041] In this disclosure, various embodiments are presented as examples of how the disclosed techniques can be implemented and / or how the disclosed techniques can be practiced in environments and scenarios. It will be apparent to those skilled in the art that various changes in form and detail can be made therein without departing from the scope of the invention. Indeed, alternative embodiments will be apparent to those skilled in the art upon reading the specification. The embodiments of the invention should not be limited to any of the exemplary embodiments described. Embodiments of this disclosure will be described with reference to the accompanying drawings. Limitations, features, and / or elements from the disclosed exemplary embodiments can be combined to create further embodiments within the scope of this disclosure. Any figures highlighting functionality and advantages are given for illustrative purposes only. The disclosed architecture is flexible and configurable enough that it can be utilized in ways other than those shown. For example, any actions listed in a flowchart can be reordered or used only optionally in certain embodiments.

[0042] The embodiments can be configured to operate as needed. For example, in wireless devices, base stations, radio environments, networks, combinations thereof, etc., the disclosed mechanisms can be executed when certain criteria are met. Example criteria may be based at least in part on, for example, wireless device or network node configuration, traffic load, initial system setup, packet size, service characteristics, combinations thereof, etc. Various example embodiments can be applied when one or more criteria are met. Therefore, example embodiments that selectively implement the disclosed protocols can be implemented.

[0043] A base station can communicate with a mixture of wireless devices. The wireless devices and / or base stations can support multiple technologies and / or multiple versions of the same technology. Wireless devices may have certain specific capabilities, depending on the type and / or capability of the wireless device. When this disclosure refers to a base station communicating with multiple wireless devices, this disclosure can refer to a subset of the total number of wireless devices in the coverage area. For example, this disclosure can mean multiple wireless devices having a given capability and in a given sector of a base station using a given LTE or 5G version. Multiple wireless devices in this disclosure can refer to a selected set of wireless devices, and / or a subset of the total number of wireless devices in the coverage area performing according to the disclosed method, etc. Multiple base stations or multiple wireless devices may exist in the coverage area that may not conform to the disclosed method; for example, these wireless devices or base stations may be based on older versions of LTE or 5G technology.

[0044] In this disclosure, “a (a)” and “an (an)”, and similar phrases, will be interpreted as “at least one” and “one or more”. Similarly, any term ending with the suffix “(s)” will be interpreted as “at least one” and “one or more”. In this disclosure, the term “may” is interpreted as “may, for example.” In other words, the term “may” indicates that the phrase following the term “may” is an example of one of a variety of suitable possibilities that may or may not be used in one or more of the various embodiments. As used herein, the terms “comprising” and “consisting of” enumerate one or more components of the element being described. The terms “comprising” and “including” are interchangeable and do not exclude the inclusion of unlisted components in the element being described. In contrast, “consisting of” provides a complete enumeration of the one or more components of the element being described. As used herein, the term “based on” should be interpreted as “at least partially based on” rather than, for example, “based on only.” As used herein, the term “and / or” indicates any possible combination of the enumerated elements. For example, "A, B and / or C" can mean A; B; C; A and B; A and C; B and C; or A, B and C.

[0045] If A and B are sets, and every element of A is also an element of B, then A is called a subset of B. In this specification, only non-empty sets and subsets are considered. For example, possible subsets of B = {cell1, cell2} are: {cell1}, {cell2}, and {cell1, cell2}. The phrase "based on" (or equivalently "at least based on") indicates that the phrase following the term "based on" is an example of one of a variety of suitable possibilities that may or may not be used in one or more different embodiments. The phrase "in response to" (or equivalently "at least in response to") indicates that the phrase following the phrase "in response to" is an example of one of a variety of suitable possibilities that may or may not be used in one or more different embodiments. The phrase "depending on" (or equivalently "at least depending on") indicates that the phrase following the phrase "depending on" is an example of one of a variety of suitable possibilities that may or may not be used in one or more different embodiments. The phrase "adopting / using" (or equivalently "at least adopting / using") indicates that the phrase following the phrase "adopting / using" is an example of one of a variety of suitable possibilities that may or may not be used in one or more different embodiments.

[0046] The term "configured" can refer to the capabilities of a device, whether the device is in an operational or non-operational state. "Configured" can refer to specific settings within the device that affect its operational characteristics, regardless of whether the device is in an operational or non-operational state. In other words, hardware, software, firmware, registers, memory values, etc., can be "configured" within the device to provide specific characteristics to the device, whether the device is in an operational or non-operational state. Similarly, the term "control messages generated in the device" can mean that the control messages have parameters that can be used to configure specific characteristics in the device or to perform certain actions in the device, regardless of whether the device is in an operational or non-operational state.

[0047] In this disclosure, a parameter (or equivalently referred to as a field or information element: IE) may contain one or more information objects, and an information object may contain one or more other objects. For example, if parameter (IE)N contains parameter (IE)M, and parameter (IE)M contains parameter (IE)K, and parameter (IE)K contains parameter (information element)J, then, for example, N contains K, and N contains J. In an example embodiment, when one or more messages contain multiple parameters, it means that a parameter among the multiple parameters is present in at least one of the one or more messages, but not necessarily in every one of the one or more messages.

[0048] Many of the proposed features are described as optional using the word "may" or parentheses. For brevity and readability, this disclosure does not explicitly describe every permutation that can be obtained by selecting from the group of optional features. This disclosure should be interpreted as explicitly disclosing all such permutations. For example, a system described as having three optional features can be embodied in seven different ways: having only one of the three possible features, having any two of the three possible features, or having three of the three possible features.

[0049] Many elements described in the disclosed embodiments can be implemented as modules. A module is defined herein as an element that performs the defined function and has the defined interface to other elements. Modules described in this disclosure can be implemented as hardware, software combined with hardware, firmware, wet hardware (e.g., hardware with biological elements), or combinations thereof, all of which may be behaviorally equivalent. For example, a module can be implemented as a software routine written in a computer language configured to be executed by a hardware machine (e.g., C, C++, Fortran, Java, Basic, Matlab, etc.) or a modeling / simulation program (e.g., Simulink, Stateflow, GNU Octave, or LabVIEW MathScript). It is possible to implement modules using physical hardware incorporating discrete or programmable analog, digital, and / or quantum hardware. Examples of programmable hardware include: computers, microcontrollers, microprocessors, application-specific integrated circuits (ASICs); field-programmable gate arrays (FPGAs); and complex programmable logic devices (CPLDs). Computers, microcontrollers, and microprocessors are programmed using languages ​​such as assembly, C, C++, etc. FPGAs, ASICs, and CPLDs are typically programmed using hardware description languages ​​(HDLs), such as VHSIC Hardware Description Language (VHDL) or Verilog, which configure connections between internal hardware modules with limited functionality on the programmable device. The aforementioned techniques are often used in combination to achieve the desired result of functional modules.

[0050] Figure 1A illustrates an example of a mobile communication network 100 in which embodiments of the present disclosure may be implemented. The mobile communication network 100 may be, for example, a Public Land Mobile Network (PLMN) operated by a network operator. As shown in Figure 1A, the mobile communication network 100 includes a core network (CN) 102, a radio access network (RAN) 104, and a radio device 106.

[0051] CN 102 can provide the wireless device 106 with an interface to one or more data networks (DNs) (such as public DNs (e.g., the Internet), private DNs, and / or carrier-internal DNs). As part of the interface functions, CN 102 can establish an end-to-end connection between the wireless device 106 and one or more DNs, authenticate the wireless device 106, and provide charging functionality.

[0052] RAN 104 can connect CN 102 to radio device 106 via radio communication through an air interface. As part of the radio communication, RAN 104 can provide scheduling, radio resource management, and retransmission protocols. The communication direction from RAN 104 to radio device 106 via the air interface is referred to as the downlink, while the communication direction from radio device 106 to RAN 104 via the air interface is referred to as the uplink. Downlink transmissions can be separated from uplink transmissions using frequency division duplex (FDD), time division duplex (TDD), and / or some combination of the two duplexing technologies.

[0053] The term "wireless device" may be used throughout this disclosure to mean and cover any mobile or fixed (non-mobile) device that requires or can use wireless communication. For example, a wireless device may be a telephone, smartphone, tablet computer, laptop computer, sensor, instrument, wearable device, Internet of Things (IoT) device, roadside unit (RSU) of a vehicle, relay node, automobile, and / or any combination thereof. The term "wireless device" also encompasses other terms including user equipment (UE), user terminal (UT), access terminal (AT), mobile station, handheld device, wireless transmit and receive unit (WTRU), and / or wireless communication device.

[0054] RAN 104 may include one or more base stations (not shown). The term "base station" may be used throughout this disclosure to refer to and encompass: Node B (associated with UMTS and / or 3G standards); Evolved Node B (eNB, associated with E-UTRA and / or 4G standards); Remote Radio Header (RRH); Baseband Processing Unit coupled to one or more RRHs; Repeater Node or Relay Node for extending the coverage area of ​​the donor Node; Next Generation Evolved Node B (ng-eNB); First Generation Node B (gNB, associated with NR and / or 5G standards); Access Point (AP, associated with, for example, WiFi or any other suitable wireless communication standard); and / or any combination thereof. A base station may include at least one gNB Central Unit (gNB-CU) and at least one gNB Distributed Unit (gNB-DU).

[0055] The base stations included in RAN 104 may include one or more sets of antennas for communicating with wireless device 106 via an air interface. For example, one or more of the base stations may include three sets of antennas to control three cells (or sectors) respectively. The size of the cells may be determined by the range within which a receiver (e.g., a base station receiver) can successfully receive transmissions from a transmitter (e.g., a wireless device transmitter) operating within the cell. The cells of the base stations may together provide radio coverage over a wide geographical area to wireless device 106 to support wireless device mobility.

[0056] Besides three-sector sites, other implementations of the base stations are also possible. For example, one or more base stations in RAN 104 can be implemented as sectorized sites with more or fewer than three sectors. One or more base stations in RAN 104 can be implemented as access points, baseband processing units coupled to several remote radio heads (RRHs), and / or repeater or relay nodes for extending the coverage area of ​​the donor node. The baseband processing unit coupled to the RRH can be part of a centralized or cloud RAN architecture, where the baseband processing unit can be centralized in a pool of baseband processing units or virtualized. Repeater nodes can amplify and replay radio signals received from the donor node. Relay nodes can perform the same / similar functions as repeater nodes, but can decode radio signals received from the donor node to remove noise before amplifying and replaying the radio signals.

[0057] RAN 104 can be deployed as a homogeneous network of macrocell base stations with similar antenna configurations and similar high-level transmission power. RAN 104 can also be deployed as a heterogeneous network. In a heterogeneous network, small cell base stations can be used to provide small coverage areas, such as coverage areas overlapping with the relatively large coverage areas provided by macrocell base stations. Small coverage areas can be provided in areas with high data traffic (or so-called "hot spots") or in areas where macrocell coverage is weak. Examples of small cell base stations, in descending order of coverage area, include: microcell base stations, picocell base stations, and femtocell base stations or femtocell base stations.

[0058] The Third Generation Partnership Project (3GPP) was established in 1998 to provide global standardization for mobile communication networks similar to mobile network 100 in Figure 1A. To date, 3GPP has defined specifications for three generations of mobile networks: third-generation (3G) networks known as Universal Mobile Telecommunications System (UMTS), fourth-generation (4G) networks known as Long Term Evolution (LTE), and fifth-generation (5G) networks known as 5G Systems (5GS). Embodiments of this disclosure are described with reference to the RAN of a 3GPP 5G network, known as Next Generation RAN (NG-RAN). These embodiments can be applied to the RAN of other mobile communication networks, such as RAN 104 in Figure 1A, the RANs of early 3G and 4G networks, and those RANs of future networks not yet specified (e.g., 3GPP 6G networks). NG-RAN implements 5G radio access technology known as New Radio (NR) and can be configured to implement 4G radio access technology or other radio access technologies, including non-3GPP radio access technologies.

[0059] Figure 1B illustrates another example mobile communication network 150 in which embodiments of the present disclosure may be implemented. The mobile communication network 150 may be, for example, a PLMN operated by a network operator. As shown in Figure 1B, the mobile communication network 150 includes a 5G core network (5G-CN) 152, an NG-RAN 154, and UEs 156A and 156B (collectively referred to as UE 156). These components may be implemented and operated in the same or similar manner as the corresponding components described with respect to Figure 1A.

[0060] 5G-CN 152 provides UE 156 with an interface to one or more DNs, such as public DNs (e.g., the Internet), private DNs, and / or operator-internal DNs. As part of the interface functionality, 5G-CN 152 can establish end-to-end connections between UE 156 and the one or more DNs, authenticate UE 156, and provide charging functions. Compared to the CNs in 3GPP 4G networks, the foundation of 5G-CN 152 can be a service-based architecture. This means that the architecture of the nodes constituting 5G-CN 152 can be defined as network functions that provide services to other network functions via the interface. The network functions of 5G-CN 152 can be implemented in several ways, including as network elements on dedicated or shared hardware, as software instances running on dedicated or shared hardware, or as virtualized functions instantiated on a platform (e.g., a cloud-based platform).

[0061] As shown in Figure 1B, 5G-CN 152 includes Access and Mobility Management Function (AMF) 158A and User Plane Function (UPF) 158B, which are shown as a single component AMF / UPF 158 in Figure 1B for clarity. UPF 158B can act as a gateway between NG-RAN 154 and the one or more DNs. Functions that UPF 158B can perform include: packet routing and forwarding, packet inspection and user plane policy rule enforcement, service usage reporting, uplink classification supporting the routing of service flows to the one or more DNs, user plane Quality of Service (QoS) processing (e.g., packet filtering, gating, uplink / downlink rate enforcement, and uplink service authentication), downlink packet buffering, and downlink data notification triggering. UPF 158B can act as an anchor point for intra / inter-Radio Access Technology (RAT) mobility, an external Protocol (or Packet) Data Unit (PDU) session point interconnected with the one or more DNs, and / or a pivot point supporting multihomed PDU sessions. UE 156 can be configured to receive services via a PDU session, which is a logical connection between the UE and the DN.

[0062] The AMF 158A can perform functions such as: Non-Access Layer (NAS) signaling termination, NAS signaling security, Access Layer (AS) security control, inter-CN node signaling for mobility between 3GPP access networks, idle mode UE reachability (e.g., paging retransmission control and execution), registration area management, intra-system and inter-system mobility support, access authentication, access authorization including roaming rights verification, mobility management control (subscription and policies), network slicing support, and / or Session Management Function (SMF) selection. NAS can refer to functions operating between the CN and the UE, and AS can refer to functions operating between the UE and the RAN.

[0063] 5G-CN 152 may include one or more additional network functions not shown in Figure 1B for clarity. For example, 5G-CN 152 may include one or more of the following: Session Management Function (SMF), NR Repository Function (NRF), Policy Control Function (PCF), Network Open Function (NEF), Unified Data Management (UDM), Application Function (AF), and / or Authentication Server Function (AUSF).

[0064] NG-RAN 154 can connect 5G-CN 152 to UE 156 via radio communication over an air interface. NG-RAN 154 may include: one or more gNBs, denoted as gNB 160A and gNB 160B (collectively referred to as gNB 160); and / or one or more ng-eNBs, denoted as ng-eNB 162A and ng-eNB 162B (collectively referred to as ng-eNB 162). gNB 160 and ng-eNB 162 may be more generally referred to as base stations. gNB 160 and ng-eNB 162 may include one or more sets of antennas for communicating with UE 156 over the air interface. For example, one or more gNBs in gNB 160 and / or one or more ng-eNBs in ng-eNB 162 may include three sets of antennas to control three cells (or sectors) respectively. The gNB 160 and ng-eNB 162 cells can work together to provide UE 156 with radio coverage over a wide geographical area to support UE mobility.

[0065] As shown in Figure 1B, gNB 160 and / or ng-eNB 162 can connect to 5G-CN 152 via the NG interface and to other base stations via the Xn interface. The NG and Xn interfaces can be established using direct physical connections and / or indirect connections via underlying transport networks (such as Internet Protocol (IP) transport networks). gNB 160 and / or ng-eNB 162 can connect to UE 156 via the Uu interface. For example, as shown in Figure 1B, gNB 160A can connect to UE 156A via the Uu interface. The NG, Xn, and Uu interfaces are associated with a protocol stack. The protocol stack associated with the interface can be used by the network elements in Figure 1B to exchange data and signaling messages and can include two planes: a user plane and a control plane. The user plane can process data of interest to the user. The control plane can process signaling messages of interest to the network elements.

[0066] The gNB 160 and / or ng-eNB 162 can connect to one or more AMF / UPF functions of the 5G-CN 152, such as AMF / UPF 158, via one or more NG interfaces. For example, the gNB 160A can connect to the UPF 158B of the AMF / UPF 158 via an NG user plane (NG-U) interface. The NG-U interface can provide user plane PDU delivery (e.g., non-guaranteed delivery) between the gNB 160A and the UPF 158B. The gNB 160A can connect to the AMF 158A via an NG control plane (NG-C) interface. The NG-C interface can provide, for example, NG interface management, UE context management, UE mobility management, NAS message delivery, paging, PDU session management, and configuration delivery and / or warning message transmission.

[0067] The gNB 160 can provide NR user plane and control plane protocol termination to the UE 156 via the Uu interface. For example, the gNB 160A can provide NR user plane and control plane protocol termination to the UE 156A via the Uu interface associated with the first protocol stack. The ng-eNB 162 can provide Evolved UMTS Terrestrial Radio Access (E-UTRA) user plane and control plane protocol termination to the UE 156 via the Uu interface, where E-UTRA refers to 3GPP 4G radio access technology. For example, the ng-eNB 162B can provide E-UTRA user plane and control plane protocol termination to the UE 156B via the Uu interface associated with the second protocol stack.

[0068] The 5G-CN 152 is described as being configured to handle NR and 4G radio access. Those skilled in the art will understand that NR can potentially connect to the 4G core network in a mode known as “non-standalone operation.” In non-standalone operation, the 4G core network is used to provide (or at least support) control plane functions (e.g., initial access, mobility, and paging). Although only one AMF / UPF 158 is shown in Figure 1B, a gNB or ng-eNB can connect to multiple AMF / UPF nodes to provide redundancy and / or load sharing across those nodes.

[0069] As discussed, the interfaces between network elements in Figure 1B (e.g., Uu, Xn, and NG interfaces) can be associated with a protocol stack used by the network elements to exchange data and signaling messages. The protocol stack can include two planes: a user plane and a control plane. The user plane handles data of interest to the user, while the control plane handles signaling messages of interest to the network elements.

[0070] Figures 2A and 2B illustrate examples of NR user plane and NR control plane protocol stacks for the Uu interface located between UE 210 and gNB 220, respectively. The protocol stacks shown in Figures 2A and 2B may be the same as or similar to those used for the Uu interface between UE 156A and gNB 160A as shown in Figure 1B, for example.

[0071] Figure 2A illustrates the five-layer NR user plane protocol stack implemented in UE 210 and gNB 220. At the bottom of the protocol stack, the Physical Layer (PHY) 211 and 221 can provide transport services to the higher layers of the stack and can correspond to Layer 1 of the Open Systems Interconnection (OSI) model. The next four protocols above PHY 211 and 221 include Media Access Control (MAC) 212 and 222, Radio Link Control (RLC) 213 and 223, Packet Data Convergence Protocol (PDCP) 214 and 224, and Service Data Application Protocol (SDAP) 215 and 225. These four protocols together can constitute Layer 2 of the OSI model or the Data Link Layer.

[0072] Figure 3 illustrates an example of services provided between protocol layers in the NR user plane protocol stack. Starting from the top of Figures 2A and 3, SDAPs 215 and 225 can perform QoS flow processing. UE 210 can receive services through a PDU session, which can be a logical connection between UE 210 and the DN. The PDU session can have one or more QoS flows. The CN's UPF (e.g., UPF 158B) can map IP packets to the one or more QoS flows of the PDU session based on QoS requirements (e.g., in terms of latency, data rate, and / or error rate). SDAPs 215 and 225 can perform mapping / demapping between the one or more QoS flows and one or more data radio bearers. The mapping / demapping between QoS flows and data radio bearers can be determined by SDAP 225 at gNB 220. SDAP 215 at UE 210 can learn the mapping between QoS flows and data radio bearers through reflected mapping or control signaling received from gNB 220. For reflective mapping, SDAP 225 at gNB 220 can mark downlink packets with QoS flow indicators (QFIs), which can be observed by SDAP 215 at UE 210 to determine the mapping / demapping between QoS flows and data radio bearers.

[0073] PDCP 214 and 224 can perform header compression / decompression to reduce the amount of data that needs to be transmitted over the air interface, can perform encryption / decryption to prevent unauthorized decoding of data transmitted over the air interface, and can perform integrity protection to ensure that control messages originate from their intended source. PDCP 214 and 224 can perform retransmission of undelivered packets, reordering and repackaging of packets, and removal of duplicate packets received due to, for example, intra-gNB handover. PDCP 214 and 224 can perform packet duplication to increase the likelihood of packet reception and remove any duplicate packets at the receiver. Packet duplication can be suitable for services requiring high reliability.

[0074] Although not shown in Figure 3, PDCPs 214 and 224 can perform mapping / demapping between split radio bearers and RLC channels in a dual connectivity scenario. Dual connectivity is a technique that allows a UE to connect to two cells or more generally to two cell groups: a primary cell group (MCG) and a secondary cell group (SCG). Split bearers are those that are handled by a cell group in dual connectivity, such as a single radio bearer (e.g., one of the radio bearers provided by PDCPs 214 and 224 as a service to SDAPs 215 and 225). PDCPs 214 and 224 can map / demapping split radio bearers between RLC channels belonging to a cell group.

[0075] RLCs 213 and 223 can respectively perform segmentation, retransmission via Automatic Repeat Request (ARQ), and removal of duplicate data units received from MACs 212 and 222. RLCs 213 and 223 can support three transmission modes: Transparent Mode (TM); Unacknowledged Mode (UM); and Acknowledged Mode (AM). Based on the transmission mode the RLC is operating in, the RLC can perform one or more of the aforementioned functions. RLC configuration can be based on the logical channel, independent of the parameter set and / or Transmission Time Interval (TTI) duration. As shown in Figure 3, RLCs 213 and 223 can provide RLC channels as services to PDCPs 214 and 224, respectively.

[0076] MACs 212 and 222 can perform multiplexing / demultiplexing of logical channels and / or mapping between logical channels and transport channels. Multiplexing / demultiplexing may include multiplexing data units belonging to one or more logical channels into / from transport blocks (TBs) delivered to / from PHYs 211 and 221. MAC 222 can be configured to perform scheduling, scheduling information reporting, and priority processing between UEs by means of dynamic scheduling. Scheduling can be performed for downlink and uplink in gNB 220 (at MAC 222). MACs 212 and 222 can be configured to perform error correction via Hybrid Automatic Repeat Request (HARQ) (e.g., one HARQ entity per carrier in the case of carrier aggregation (CA), priority processing between logical channels of UE 210 by means of logical channel priority ordering, and / or padding. MACs 212 and 222 may support one or more parameter sets and / or transmission timing. In the example, the mapping constraints in the logical channel priority ordering can control which set of parameters and / or transmission timing the logical channel can use. As shown in Figure 3, MACs 212 and 222 can provide logical channels as services to RLCs 213 and 223.

[0077] PHYs 211 and 221 can perform transport channel-to-physical channel mapping and digital and analog signal processing functions for transmitting and receiving information over the air interface. These digital and analog signal processing functions may include, for example, encoding / decoding and modulation / demodulation. PHYs 211 and 221 can perform multi-antenna mapping. As shown in Figure 3, PHYs 211 and 221 can provide one or more transport channels as a service to MACs 212 and 222.

[0078] Figure 4A illustrates an example downlink data flow through the NR user plane protocol stack. Figure 4A shows the downlink data flow through the NR user plane protocol stack to generate three IP packets (n, n+1, and m) of two TB at gNB 220. The uplink data flow through the NR user plane protocol stack can be similar to the downlink data flow depicted in Figure 4A.

[0079] The downlink data flow in Figure 4A begins when SDAP 225 receives three IP packets from one or more QoS flows and maps these three packets to radio bearers. In Figure 4A, SDAP 225 maps IP packets n and n+1 to the first radio bearer 402 and IP packet m to the second radio bearer 404. An SDAP header (marked with "H" in Figure 4A) is added to the IP packets. Data units from / to a higher protocol layer are called lower protocol layer service data units (SDUs), and data units to / from a lower protocol layer are called higher protocol layer protocol data units (PDUs). As shown in Figure 4A, the data unit from SDAP 225 is the SDU of the lower protocol layer PDCP 224 and the PDU of SDAP 225.

[0080] The remaining protocol layers in Figure 4A can perform their associated functions (e.g., with respect to Figure 3), add corresponding headers, and forward their respective outputs to the next lower layer. For example, PDCP 224 can perform IP header compression and encryption and forward its output to RLC 223. RLC 223 can optionally perform fragmentation (e.g., as shown with respect to IP packet m in Figure 4A) and forward its output to MAC 222. MAC 222 can multiplex many RLC PDUs and can attach MAC subheaders to RLC PDUs to form transport blocks. In NR, MAC subheaders can be distributed throughout the MAC PDUs, as shown in Figure 4A. In LTE, MAC subheaders can be located entirely at the beginning of the MAC PDU. The NR MAC PDU structure can reduce processing time and associated latency because the MAC PDU subheaders can be computed before assembling the complete MAC PDU.

[0081] Figure 4B shows an example format of the MAC subheader in a MAC PDU. The MAC subheader includes: an SDU length field indicating the length (e.g., in bytes) of the MAC SDU to which the MAC subheader corresponds; a Logical Channel Identifier (LCID) field identifying the logical channel from which the MAC SDU originates to assist in the demultiplexing process; a flag (F) indicating the size of the SDU length field; and a reserved bit (R) field for future use.

[0082] Figure 4B further illustrates MAC control elements (CEs) inserted into a MAC PDU by a MAC (such as MAC 223 or MAC 222). For example, Figure 4B shows two MAC CEs inserted into a MAC PDU. MAC CEs can be inserted at the beginning of downlink transmissions in the MAC PDU (as shown in Figure 4B) and at the end of uplink transmissions in the MAC PDU. MAC CEs can be used for in-band control signaling. Example MAC CEs include: scheduling-related MAC CEs, such as buffer status reports and power margin reports; activation / deactivation MAC CEs, such as those used for PDCP repeat detection, channel state information (CSI) reports, sounding reference signal (SRS) transmissions, and activation / deactivation of previously configured components; discontinuous reception (DRX)-related MAC CEs; timing advance MAC CEs; and random access-related MAC CEs. A MAC subheader with a format similar to that described with respect to the MAC SDU may exist before the MAC CE, and the MAC CE may be identified by a reserved value in the LCID field indicating the type of control information included in the MAC CE.

[0083] Before describing the NR control plane protocol stack, we will first describe the mapping between logical channels, transport channels, and physical channels, as well as channel types. One or more of these channels can be used to perform functions associated with the NR control plane protocol stack, which will be described later below.

[0084] Figures 5A and 5B illustrate the mapping between logical channels, transport channels, and physical channels for downlink and uplink, respectively. Information is transmitted through channels between the RLC, MAC, and PHY of the NR protocol stack. Logical channels can be used between the RLC and MAC and can be classified as control channels carrying control and configuration information in the NR control plane, or as service channels carrying data in the NR user plane. Logical channels can be classified as dedicated logical channels for a specific UE, or as common logical channels that can be used by more than one UE. Logical channels can also be defined by the type of information they carry. The set of logical channels defined by NR includes, for example: -- Paging Control Channel (PCCH), which carries paging messages for paging UEs whose location is unknown to the network at the cell level; -- Broadcast Control Channel (BCCH), which carries system information messages in the form of a Master Information Block (MIB) and several System Information Blocks (SIBs), wherein the system information messages can be used by the UE to obtain information about how the cell is configured and how to operate within the cell; -- Common Control Channel (CCCH), which carries control messages and random access; -- Dedicated Control Channel (DCCH), which carries control messages to a specific UE / carries control messages from a specific UE to configure the UE; and -- Dedicated Traffic Channel (DTCH), which carries user data to a specific UE / carries user data from a specific UE.

[0085] Transport channels are used between the MAC and PHY layers and can be defined by how the information they carry is transmitted over the air interface. The set of transport channels defined by NR includes, for example: -- Paging channel (PCH), which carries paging messages originating from the PCCH; -- Broadcast channel (BCH), which carries MIBs from the BCCH; -- Downlink Shared Channel (DL-SCH), which carries downlink data and signaling messages, including SIBs from the BCCH; -- Uplink Shared Channel (UL-SCH), which carries uplink data and signaling messages; and -- Random Access Channel (RACH), which allows the UE to access the network without any prior scheduling.

[0086] The PHY can use physical channels to transfer information between processing levels of the PHY. A physical channel can be a set of associated time-frequency resources used to carry information from one or more transport channels. The PHY can generate control information to support lower-level PHY operations and provide this control information to lower levels of the PHY via physical control channels (referred to as L1 / L2 control channels). The set of physical channels and physical control channels defined by NR includes, for example: --Physical Broadcast Channel (PBCH), which carries MIBs from the BCH; --Physical Downlink Shared Channel (PDSCH), which carries downlink data and signaling messages from the DL-SCH and paging messages from the PCH; --Physical Downlink Control Channel (PDCCH), which carries downlink control information (DCI), which may include downlink scheduling commands, uplink scheduling authorization, and uplink power control commands. --Physical Uplink Shared Channel (PUSCH), used to carry uplink data and signaling messages from UL-SCH, and in some cases, uplink control information (UCI) as described below; --Physical Uplink Control Channel (PUCCH), used to carry UCI, which may include HARQ acknowledgment, channel quality indicator (CQI), precoding matrix indicator (PMI), rank indicator (RI), and scheduling request (SR); and --Physical Random Access Channel (PRACH), used for random access.

[0087] Similar to the physical control channel, the physical layer generates physical signals to support its low-level operations. As shown in Figures 5A and 5B, the physical layer signals defined by the NR include: Primary Synchronization Signal (PSS), Secondary Synchronization Signal (SSS), Channel State Information Reference Signal (CSI-RS), Demodulation Reference Signal (DMRS), Sounding Reference Signal (SRS), and Phase Tracking Reference Signal (PT-RS). These physical layer signals will be described in more detail below.

[0088] Figure 2B illustrates an example NR control plane protocol stack. As shown in Figure 2B, the NR control plane protocol stack can use the same / similar first four protocol layers as the example NR user plane protocol stack. These four protocol layers include PHY 211 and 221, MAC 212 and 222, RLC 213 and 223, and PDCP 214 and 224. Instead of having SDAP 215 and 225 at the top of the stack as in the NR user plane protocol stack, the NR control plane protocol stack has Radio Resource Control (RRC) 216 and 226 and NAS protocols 217 and 237 at the top of the NR control plane protocol stack.

[0089] NAS protocols 217 and 237 can provide control plane functions between UE 210 and AMF 230 (e.g., AMF 158A) or more generally between UE 210 and CN. NAS protocols 217 and 237 can provide control plane functions between UE 210 and AMF 230 via signaling messages known as NAS messages. There is no direct path through which NAS messages can be transmitted between UE 210 and AMF 230. NAS messages can be transmitted using the AS of the Uu and NG interfaces. NAS protocols 217 and 237 can provide control plane functions such as authentication, security, connection setup, mobility management, and session management.

[0090] RRC 216 and 226 can provide control plane functionality between UE 210 and gNB 220, or more generally between UE 210 and RAN. RRC 216 and 226 can provide control plane functionality between UE 210 and gNB 220 via signaling messages known as RRC messages. RRC messages can be transmitted between UE 210 and RAN using signaling radio bearers and the same / similar PDCP, RLC, MAC, and PHY protocol layers. MAC can multiplex control plane and user plane data into the same transport block (TB). RRC 216 and 226 can provide control plane functions such as: broadcasting system information related to AS and NAS; paging initiated by CN or RAN; establishment, maintenance, and release of RRC connections between UE 210 and RAN; security functions including key management; establishment, configuration, maintenance, and release of signaling radio bearers and data radio bearers; mobility functions; QoS management functions; UE measurement reporting and control of said reports; detection and recovery of radio link failures (RLFs); and / or NAS messaging. As part of establishing an RRC connection, RRC 216 and 226 can establish an RRC context, which may involve configuring parameters for communication between UE 210 and RAN.

[0091] Figure 6 is an example diagram illustrating the RRC state transitions of a UE. The UE may be the same as or similar to the radio device 106 depicted in Figure 1A, the UE 210 depicted in Figures 2A and 2B, or any other radio device described in this disclosure. As shown in Figure 6, the UE may be in at least one of three RRC states: RRC connected 602 (e.g., RRC_CONNECTED), RRC idle 604 (e.g., RRC_IDLE), and RRC inactive 606 (e.g., RRC_INACTIVE).

[0092] In RRC connection 602, the UE has an established RRC context and may have at least one RRC connection with a base station. The base station may be similar to one or more of the following: one or more base stations included in RAN 104 depicted in FIG. 1A; one of gNB 160 or ng-eNB 162 depicted in FIG. 1B; gNB 220 depicted in FIG. 2A and FIG. 2B; or any other base station described in this disclosure. The base station connected to the UE may have an RRC context for the UE. The RRC context, referred to as the UE context, may contain parameters for communication between the UE and the base station. These parameters may include, for example: one or more AS contexts; one or more radio link configuration parameters; bearer configuration information (e.g., relating to data radio bearers, signaling radio bearers, logical channels, QoS flows, and / or PDU sessions); security information; and / or PHY, MAC, RLC, PDCP, and / or SDAP layer configuration information. When in RRC connection 602, the UE's mobility may be managed by the RAN (e.g., RAN 104 or NG-RAN 154). The UE can measure signal levels (e.g., reference signal levels) from the serving cell and neighboring cells and report these measurements to the base station currently serving the UE. The serving base station of the UE can request a cell transfer to one of the neighboring base stations based on the reported measurements. The RRC state can transition from RRC connection 602 to RRC idle 604 via connection release procedure 608, or to RRC inactive 606 via connection deactivation procedure 610.

[0093] In RRC idle 604, an RRC context may not have been established for the UE. In RRC idle 604, the UE may not have an RRC connection with the base station. When in RRC idle 604, the UE may be in sleep mode most of the time (e.g., to conserve battery power). The UE may wake up periodically (e.g., once in each discontinuous reception cycle) to monitor paging messages from the RAN. The UE's mobility can be managed by the UE through a procedure called cell reselection. The RRC state can be transitioned from RRC idle 604 to RRC connected 602 through connection establishment procedure 612, which may involve a random access procedure, as discussed in more detail below.

[0094] In RRC inactivity 606, the previously established RRC context is maintained in both the UE and the base station. This allows for a faster transition to RRC connection 602 with reduced signaling overhead compared to the transition from RRC idle 604 to RRC connected 602. While in RRC inactivity 606, the UE can be in a sleep state, and the UE's mobility can be managed by the UE via cell reselection. The RRC state can transition from RRC inactivity 606 to RRC connected 602 via connection resumption procedure 614, or to RRC idle 604 via connection release procedure 616, which can be the same as or similar to connection release procedure 608.

[0095] RRC states can be associated with mobility management mechanisms. In RRC Idle 604 and RRC Inactive 606, mobility is managed by the UE through cell reselection. The purpose of mobility management in RRC Idle 604 and RRC Inactive 606 is to allow the network to notify the UE of events via paging messages without having to broadcast paging messages across the entire mobile network. The mobility management mechanisms used in RRC Idle 604 and RRC Inactive 606 allow the network to track the UE at the cell group level, so that paging messages can be broadcast on the cells in the cell group where the UE currently resides, rather than across the entire mobile network. The mobility management mechanisms used in RRC Idle 604 and RRC Inactive 606 track the UE at the cell group level. These mobility management mechanisms can do this using groupings of different granularities. For example, there can be three levels of cell grouping granularity: a single cell; cells within a RAN area identified by a RAN Area Identifier (RAI); and cells within a group of RAN areas called tracking areas and identified by a Tracking Area Identifier (TAI).

[0096] A tracking area can be used to track the UE at the CN level. The CN (e.g., CN 102 or 5G-CN 152) can provide the UE with a list of TAIs associated with the UE's registration area. If the UE moves to a cell associated with a TAI not included in the list of TAIs associated with the UE's registration area via cell reselection, the UE can perform a registration update with the CN to allow the CN to update the UE's location and provide the UE with a new UE registration area.

[0097] RAN areas can be used to track UEs at the RAN level. For a UE in an RRC inactive 606 state, a RAN notification area can be assigned to that UE. A RAN notification area can contain one or more cell identifiers, a list of RAIs, or a list of TAIs. In the example, a base station can belong to one or more RAN notification areas. In the example, a cell can belong to one or more RAN notification areas. If a UE moves via cell reselection to a cell not included in the RAN notification area assigned to it, the UE can perform a notification area update on the RAN to update its RAN notification area.

[0098] The base station storing the RRC context for the UE, or the UE's last serving base station, may be referred to as the anchor base station. The anchor base station may maintain the RRC context for the UE at least during the period when the UE remains in the anchor base station's RAN notification area and / or during the period when the UE remains in RRC inactivity 606.

[0099] As shown in Figure 1B, gNB 160 can be divided into two parts: a central unit (gNB-CU) and one or more distributed units (gNB-DU). The gNB-CU can be coupled to one or more gNB-DUs using an F1 interface. The gNB-CU may contain RRC, PDCP, and SDAP. The gNB-DU may contain RLC, MAC, and PHY.

[0100] In NR, the physical signal and physical channel (discussed with respect to Figures 5A and 5B) can be mapped onto Orthogonal Frequency Division Multiplexing (OFDM) symbols. OFDM is a multi-carrier communication scheme that transmits data over F orthogonal subcarriers (or tones). Before transmission, the data can be mapped onto a series of complex symbols called source symbols (e.g., M-QAM or M-PSK symbols) and divided into F parallel symbol streams. These F parallel symbol streams can be treated as if they were in the frequency domain and used as input to an Inverse Fast Fourier Transform (IFFT) block that transforms them into the time domain. The IFFT block takes F source symbols at a time (one source symbol from each of the F parallel symbol streams) and uses each source symbol to modulate the amplitude and phase of one of the F sinusoidal basis functions corresponding to the F orthogonal subcarriers. The output of the IFFT block can be F time-domain samples representing the sum of the F orthogonal subcarriers. The F time-domain samples can form a single OFDM symbol. After some processing (e.g., addition of a cyclic prefix) and upsampling, the OFDM symbol provided by the IFFT block can be transmitted over the air interface at the carrier frequency. The F parallel symbol streams can be mixed using an FFT block before being processed by the IFFT block. This operation produces a Discrete Fourier Transform (DFT) precoded OFDM symbol, which can be used by the UE in the uplink to reduce the peak-to-average power ratio (PAPR). The inverse processing of the OFDM symbol at the receiver can be performed using the FFT block to recover the data mapped to the source symbol.

[0101] Figure 7 illustrates an example configuration of NR frames in which OFDM symbols are grouped. NR frames can be identified by a System Frame Number (SFN). SFNs can repeat at a period of 1024 frames. As shown, the duration of an NR frame can be 10 milliseconds (ms), and it can comprise 10 subframes with a duration of 1 ms. Subframes can be divided into time slots, each time slot comprising, for example, 14 OFDM symbols.

[0102] The duration of a time slot can depend on the set of parameters used for the OFDM symbols in that time slot. In NR, flexible parameter sets are supported to accommodate different cell deployments (e.g., cells with carrier frequencies below 1 GHz, up to cells with carrier frequencies in the mmWave range). The parameter set can be defined in terms of subcarrier spacing and cyclic prefix duration. For the parameter set in NR, the subcarrier spacing can be scaled up from a baseline subcarrier spacing of 15 kHz by powers of two, and the cyclic prefix duration can be scaled down from a baseline cyclic prefix duration of 4.7 μs by powers of two. For example, NR defines parameter sets with the following combinations of subcarrier spacing / cyclic prefix duration: 15 kHz / 4.7 μs; 30 kHz / 2.3 μs; 60 kHz / 1.2 μs; 120 kHz / 0.59 μs; and 240 kHz / 0.29 μs.

[0103] A time slot can have a fixed number of OFDM symbols (e.g., 14 OFDM symbols). Parameter sets with higher subcarrier spacing have shorter time slot durations and correspondingly more time slots per subframe. Figure 7 illustrates this transmission structure with time slot durations and time slots per subframe related to the parameter set (a parameter set with a subcarrier spacing of 240 kHz is not shown in Figure 7 for illustration). Subframes in the NR can be used as a time reference independent of the parameter set, while time slots can be used as units for scheduling uplink and downlink transmissions. To support low latency, scheduling in the NR can be separated from the time slot duration and begin at any OFDM symbol, continuing to transmit as many symbols as needed. These partial time slot transmissions can be referred to as micro-time slots or sub-time slot transmissions.

[0104] Figure 8 illustrates an example configuration of time slots in the time and frequency domains of an NR carrier. The time slots comprise resource elements (REs) and resource blocks (RBs). An RE is the smallest physical resource in an NR. An RE spans one OFDM symbol in the time domain via a subcarrier in the frequency domain, as shown in Figure 8. An RB spans twelve consecutive REs in the frequency domain, as shown in Figure 8. An NR carrier can be limited to a width of 275 RBs, or 275 × 12 = 3300 subcarriers. With this limitation, for subcarrier spacings of 15 kHz, 30 kHz, 60 kHz, and 120 kHz, the NR carrier can be limited to 50 MHz, 100 MHz, 200 MHz, and 400 MHz, respectively, where the 400 MHz bandwidth can be set based on a bandwidth limit of 400 MHz per carrier.

[0105] Figure 8 illustrates a single set of parameters used across the entire bandwidth of an NR carrier. In other example configurations, multiple sets of parameters can be supported on the same carrier.

[0106] NR can support wide carrier bandwidths (e.g., up to 400 MHz for a subcarrier spacing of 120 kHz). Not all UEs can receive the full carrier bandwidth (e.g., due to hardware limitations). Moreover, receiving the full carrier bandwidth can be prohibitively expensive in terms of UE power consumption. In the example, to reduce power consumption and / or for other purposes, the UE can adjust the size of its receive bandwidth based on the amount of traffic it plans to receive. This is called bandwidth adaptation.

[0107] The NR defines a Bandwidth Component (BWP) to support UEs that cannot receive the full carrier bandwidth and to support bandwidth adaptation. In an example, a BWP can be defined by a subset of consecutive Relay Buses (RBs) on a carrier. A UE can be configured (e.g., via the RRC layer) to have one or more downlink BWPs and one or more uplink BWPs per serving cell (e.g., up to four downlink BWPs and up to four uplink BWPs per serving cell). At a given time, one or more of the configured BWPs for the serving cell can be active. These one or more BWPs can be referred to as the active BWPs of the serving cell. When the serving cell is configured with a secondary uplink carrier, the serving cell can have one or more first active BWPs on the uplink carrier and one or more second active BWPs on the secondary uplink carrier.

[0108] For unpaired spectrum, if the downlink BWP index of the downlink BWP is the same as the uplink BWP index of the uplink BWP, then the downlink BWP from the set of configured downlink BWPs can link with the uplink BWP from the set of configured uplink BWPs. For unpaired spectrum, the UE can expect the center frequency of the downlink BWP to be the same as the center frequency of the uplink BWP.

[0109] For a set of configured downlink BWPs on the primary cell (PCell), the base station can configure a UE with one or more control resource sets (CORESETs) for at least one search space. A search space is a set of time-domain and frequency-domain locations where a UE can locate control information. The search space can be a UE-specific search space or a common search space (potentially usable by multiple UEs). For example, the base station can configure a common search space for the UE on the PCell or primary / secondary cell (PSCell) within active downlink BWPs.

[0110] For an uplink BWP in the set of configured uplink BWPs, the BS can configure one or more resource sets for the UE to transmit one or more PUCCHs. The UE can receive downlink reception (e.g., PDCCH or PDSCH) in the downlink BWP based on the configured set of parameters (e.g., subcarrier spacing and cyclic prefix duration) used for the downlink BWP. The UE can transmit uplink transmissions (e.g., PUCCH or PUSCH) in the uplink BWP based on the configured set of parameters (e.g., subcarrier spacing and cyclic prefix length of the uplink BWP).

[0111] One or more BWP indicator fields may be provided in the downlink control information (DCI). The value of the BWP indicator field can indicate which BWP in the set of configured BWPs is the active downlink BWP for one or more downlink receptions. The value of the one or more BWP indicator fields can indicate the active uplink BWP for one or more uplink transmissions.

[0112] The base station can semi-statically configure a default downlink BWP for the UE within a set of configured downlink BWPs associated with the PCell. If the base station does not provide a default downlink BWP to the UE, the default downlink BWP can be the initial active downlink BWP. The UE can determine which BWP is the initial active downlink BWP based on the CORESET configuration obtained using the PBCH.

[0113] The base station can configure the BWP inactivity timer value for the UE for the PCell. The UE can start or restart the BWP inactivity timer at any appropriate time. For example, the UE can start or restart the BWP inactivity timer when: (a) the UE detects a DCI indicating an active downlink BWP other than the default downlink BWP for paired spectrum operation; or (b) the UE detects a DCI indicating an active downlink BWP or active uplink BWP other than the default downlink BWP or uplink BWP for unpaired spectrum operation. If the UE does not detect a DCI within a time interval (e.g., 1 ms or 0.5 ms), the UE can run the BWP inactivity timer toward its expiration (e.g., an increment from zero to the BWP inactivity timer value, or a decrement from the BWP inactivity timer value to zero). When the BWP inactivity timer expires, the UE can switch from the active downlink BWP to the default downlink BWP.

[0114] In the example, the base station can semi-statically configure the UE using one or more BWPs. The UE can switch the active BWP from the first BWP to the second BWP in response to receiving a DCI indicating that the second BWP is the active BWP and / or in response to the expiration of a BWP inactivity timer (e.g., in the case that the second BWP is the default BWP).

[0115] Downlink and uplink BWP handovers can be performed independently in paired spectrum (where BWP handover refers to switching from the currently active BWP to a non-currently active BWP). In unpaired spectrum, downlink and uplink BWP handovers can be performed simultaneously. Handovers can occur between configured BWPs based on RRC signaling, DCI, the expiration of a BWP inactivity timer, and / or the initiation of random access.

[0116] Figure 9 illustrates an example of bandwidth adaptation using three configured BWPs with an NR carrier. A UE configured with these three BWPs can switch from one BWP to another at a handover point. In the example shown in Figure 9, the BWPs include: BWP 902 with a bandwidth of 40 MHz and a subcarrier spacing of 15 kHz; BWP 904 with a bandwidth of 10 MHz and a subcarrier spacing of 15 kHz; and BWP 906 with a bandwidth of 20 MHz and a subcarrier spacing of 60 kHz. BWP 902 can be the initial active BWP, and BWP 904 can be the default BWP. The UE can switch between BWPs at a handover point. In the example of Figure 9, the UE can switch from BWP 902 to BWP 904 at handover point 908. The handover at handover point 908 can occur for any suitable reason, such as in response to the expiration of a BWP inactivity timer (indicating a switch to the default BWP) and / or in response to receiving a DCI indicating that BWP 904 is the active BWP. The UE may switch from active BWP 904 to BWP 906 at handover point 910 in response to receiving a DCI indicating that BWP 906 is the active BWP. The UE may switch from active BWP 906 to BWP 904 at handover point 912 in response to the expiration of a BWP inactivity timer and / or in response to receiving a DCI indicating that BWP 904 is the active BWP. The UE may switch from active BWP 904 to BWP 902 at handover point 914 in response to receiving a DCI indicating that BWP 902 is the active BWP.

[0117] If a UE is configured for a secondary cell with default downlink BWP and timer values ​​from a set of configured downlink BWPs, the UE procedure for switching BWPs on the secondary cell can be the same as / similar to that on the primary cell. For example, the UE can use these values ​​on the secondary cell in the same / similar way as the UE would use the timer values ​​and default downlink BWP of the primary cell.

[0118] To provide higher data rates, carrier aggregation (CA) can be used to combine two or more carriers and transmit them simultaneously to / from the same UE. The aggregated carriers in CA can be referred to as component carriers (CCs). When using CA, there are multiple serving cells for the UE, with one serving cell per CC. A CC can have three configurations in the frequency domain.

[0119] Figure 10A illustrates three CA configurations with two CCs. In the intra-band contiguous configuration 1002, the two CCs are aggregated in the same frequency band (band A) and positioned directly adjacent to each other within the band. In the intra-band discontinuous configuration 1004, the two CCs are aggregated in the same frequency band (band A) and separated by a gap within the band. In the inter-band configuration 1006, the two CCs are located in frequency bands (band A and band B).

[0120] In the example, up to 32 CCs can be aggregated. Aggregated CCs can have the same or different bandwidths, subcarrier spacing, and / or duplex schemes (TDD or FDD). The serving cell for the UE using CA can have downlink CCs. For FDD, one or more uplink CCs can optionally be configured for the serving cell. For example, the ability to aggregate more downlink carriers than uplink carriers can be useful when the UE has more data traffic in the downlink than in the uplink.

[0121] When using CA, one of the aggregated cells used for the UE can be referred to as the primary cell (PCell). The PCell can be the serving cell to which the UE initially connects during RRC connection establishment, re-establishment, and / or handover. The PCell provides the UE with NAS mobility information and security input. The UE can have different PCells. In the downlink, the carrier corresponding to the PCell can be referred to as the downlink primary CC (DL PCC). In the uplink, the carrier corresponding to the PCell can be referred to as the uplink primary CC (UL PCC). Other aggregated cells used for the UE can be referred to as secondary cells (SCells). In the example, the SCell can be configured after the PCell is configured for the UE. For example, the SCell can be configured via an RRC connection reconfiguration procedure. In the downlink, the carrier corresponding to the SCell can be referred to as the downlink secondary CC (DL SCC). In the uplink, the carrier corresponding to the SCell can be referred to as the uplink secondary CC (UL SCC).

[0122] Configured SCells for a UE can be activated and deactivated based on, for example, service and channel conditions. Deactivation of a SCell can mean stopping PDCCH and PDSCH reception on the SCell, and stopping PUSCH, SRS, and CQI transmissions on the SCell. Configured SCells can be activated and deactivated using the MAC CE shown in Figure 4B. For example, the MAC CE can use a bitmap (e.g., one bit per SCell) to indicate which SCells for the UE (e.g., in a subset of configured SCells) are activated or deactivated. Configured SCells can be deactivated in response to the expiration of a SCell deactivation timer (e.g., one SCell deactivation timer per SCell).

[0123] Downlink control information for a cell (such as scheduling assignment and scheduling grant) can be transmitted on the cell corresponding to the assignment and grant, a process known as self-scheduling. A cell's DCI can be transmitted on another cell, a process known as cross-carrier scheduling. Uplink control information used for aggregation cells (e.g., HARQ acknowledgments and channel state feedback such as CQI, PMI, and / or RI) can be transmitted on the PCell's PUCCH. For a large number of aggregation downlink CCs, the PCell's PUCCH may become overloaded. Cells can be divided into multiple PUCCH groups.

[0124] Figure 10B illustrates an example of how aggregated cells can be configured into one or more PUCCH groups. PUCCH group 1010 and PUCCH group 1050 can each include one or more downlink CCs. In the example of Figure 10B, PUCCH group 1010 includes three downlink CCs: PCell 1011, SCell 1012, and SCell 1013. PUCCH group 1050 in this example includes three downlink CCs: PCell 1051, SCell 1052, and SCell 1053. One or more uplink CCs can be configured as PCell 1021, SCell 1022, and SCell 1023. One or more other uplink CCs can be configured as primary SCell (PSCell) 1061, SCell 1062, and SCell 1063. Uplink control information (UCI) related to the downlink CC of PUCCH group 1010 (shown as UCI 1031, UCI 1032, and UCI 1033) can be transmitted in the uplink of PCell 1021. Uplink control information (UCI) related to the downlink CC of PUCCH group 1050 (shown as UCI 1071, UCI 1072, and UCI 1073) can be transmitted in the uplink of PSCell 1061. In the example, if the aggregated cell depicted in Figure 10B is not divided into PUCCH group 1010 and PUCCH group 1050, a single uplink PCell transmits UCI related to the downlink CC, and the PCell may become overloaded. Overload can be prevented by dividing the transmission of UCI between PCell 1021 and PSCell 1061.

[0125] A physical cell ID and a cell index can be assigned to a cell that includes a downlink carrier and an optional uplink carrier. The physical cell ID or cell index can identify the cell's downlink carrier and / or uplink carrier, for example, depending on the context in which the physical cell ID is used. The physical cell ID can be determined using synchronization signals transmitted on the downlink component carriers. The cell index can be determined using RRC messages. In this disclosure, the physical cell ID can be referred to as a carrier ID, and the cell index can be referred to as a carrier index. For example, when this disclosure relates to a first physical cell ID for a first downlink carrier, this disclosure can mean that the first physical cell ID is used for a cell containing the first downlink carrier. The same / similar concepts can be applied, for example, to carrier activation. When this disclosure indicates that a first carrier is activated, this specification can mean that a cell containing the first carrier is activated.

[0126] In CA, the multi-carrier nature of the PHY can be exposed to the MAC. In the example, the HARQ entity can operate on the serving cell. Transport blocks can be generated based on the assignment / grant of each serving cell. Transport blocks and their potential HARQ retransmissions can be mapped to the serving cell.

[0127] In the downlink, the base station can transmit one or more reference signals (RS) (e.g., unicast, multicast, and / or broadcast) to the UE (e.g., PSS, SSS, CSI-RS, DMRS, and / or PT-RS, as shown in Figure 5A). In the uplink, the UE can transmit one or more RS to the base station (e.g., DMRS, PT-RS, and / or SRS, as shown in Figure 5B). PSS and SSS can be transmitted by the base station and used by the UE to synchronize with the base station. PSS and SSS can be provided in a synchronization signal (SS) / physical broadcast channel (PBCH) block that includes PSS, SSS, and PBCH. The base station can periodically transmit bursts of SS / PBCH blocks.

[0128] Figure 11A illustrates an example of the structure and location of SS / PBCH blocks. A burst of SS / PBCH blocks may include one or more SS / PBCH blocks (e.g., four SS / PBCH blocks, as shown in Figure 11A). Bursts may be transmitted periodically (e.g., every 2 frames or 20 ms). Bursts may be limited to half-frames (e.g., a first half-frame lasting 5 ms). It should be understood that Figure 11A is an example, and these parameters (the number of SS / PBCH blocks per burst, the periodicity of the burst, the burst location within a frame) may be configured based on, for example, the carrier frequency of the cell in which the SS / PBCH blocks are transmitted; the parameter set or subcarrier spacing of the cell; the configuration performed by the network (e.g., using RRC signaling); or any other suitable factors. In the example, the UE may assume the subcarrier spacing of the SS / PBCH blocks based on the carrier frequency being monitored, unless the radio network configures the UE to assume a different subcarrier spacing.

[0129] The SS / PBCH block can span one or more OFDM symbols in the time domain (e.g., four OFDM symbols, as shown in the example of Figure 11A) and can span one or more subcarriers in the frequency domain (e.g., 240 consecutive subcarriers). The PSS, SSS, and PBCH can share a common center frequency. The PSS can be transmitted first and can span, for example, one OFDM symbol and 127 subcarriers. The SSS can be transmitted after the PSS (e.g., two symbols later) and can span one OFDM symbol and 127 subcarriers. The PBCH can be transmitted after the PSS (e.g., spanning the next three OFDM symbols) and can span 240 subcarriers.

[0130] The UE may not know the location of the SS / PBCH block in the time and frequency domains (e.g., when the UE is searching for a cell). To find and select a cell, the UE can monitor the carrier of the PSS. For example, the UE can monitor the frequency location within the carrier. If the PSS is not found after a certain duration (e.g., 20 ms), the UE can search for the PSS at different frequency locations within the carrier, as indicated by the synchronization grating. If the PSS is found at a certain location in the time and frequency domains, the UE can determine the locations of the SSS and PBCH based on the known structure of the SS / PBCH block, respectively. The SS / PBCH block can be a cell-defined SS block (CD-SSB). In the example, the primary cell can be associated with the CD-SSB. The CD-SSB can be located on the synchronization grating. In the example, cell selection / search and / or reselection can be based on the CD-SSB.

[0131] The SS / PBCH block can be used by the UE to determine one or more parameters of the cell. For example, the UE can determine the physical cell identifier (PCI) of the cell based on the sequence of the PSS and SSS, respectively. The UE can determine the location of the cell's frame boundary based on the location of the SS / PBCH block. For example, the SS / PBCH block can indicate that it has been transmitted according to a transmission mode in which the SS / PBCH block is at a known distance from the frame boundary.

[0132] The PBCH can use QPSK modulation and forward error correction (FEC). FEC can use polarity coding. One or more symbols spanned by the PBCH can carry one or more DMRS for PBCH demodulation. The PBCH can include an indication of the cell's current system frame number (SFN) and / or an SS / PBCH block timing index. These parameters can help the UE synchronize time with the base station. The PBCH can include a Master Information Block (MIB) to provide one or more parameters to the UE. The MIB can be used by the UE to locate the Residual Minimum System Information (RMSI) associated with the cell. The RMSI can include System Information Block Type 1 (SIB1). SIB1 can contain information required for the UE to access the cell. The UE can use one or more parameters of the MIB to monitor the PDCCH that can be used to schedule the PDSCH. The PDSCH can include SIB1. SIB1 can be decoded using the parameters provided in the MIB. The PBCH can indicate that SIB1 does not exist. Based on the PBCH indicating that SIB1 does not exist, the UE can point to a frequency. The UE can search for SS / PBCH blocks at the frequency pointed to by the UE.

[0133] The UE may assume that one or more SS / PBCH blocks transmitted using the same SS / PBCH block index are quasi-co-located (QCLed) (e.g., having the same / similar Doppler spread, Doppler shift, average gain, average delay, and / or spatial Rx parameters). The UE may not assume QCL for SS / PBCH blocks transmitted with different SS / PBCH block indices.

[0134] SS / PBCH blocks (e.g., those within a half-frame) can be transmitted in spatial directions (e.g., using different beams across the coverage area of ​​the cell). In the example, the first SS / PBCH block can be transmitted in the first spatial direction using the first beam, and the second SS / PBCH block can be transmitted in the second spatial direction using the second beam.

[0135] In the example, within the carrier's frequency range, the base station can transmit multiple SS / PBCH blocks. In the example, the first PCI of the first SS / PBCH block among the multiple SS / PBCH blocks can be different from the second PCI of the second SS / PBCH block among the multiple SS / PBCH blocks. The PCIs of SS / PBCH blocks transmitted at different frequency locations can be different or the same.

[0136] CSI-RS can be transmitted by the base station and used by the UE to acquire Channel State Information (CSI). The base station can utilize one or more CSI-RS to configure the UE for channel estimation or any other suitable purpose. The base station can utilize one or more of the same / similar CSI-RS to configure the UE. The UE can measure the one or more CSI-RS. The UE can estimate the downlink channel state and / or generate a CSI report based on the measurements of the one or more downlink CSI-RS. The UE can provide the CSI report to the base station. The base station can use the feedback provided by the UE (e.g., the estimated downlink channel state) to perform link adaptation.

[0137] The base station can semi-statically configure the UE using one or more CSI-RS resource sets. CSI-RS resources can be associated with location and periodicity in the time and frequency domains. The base station can selectively activate and / or deactivate CSI-RS resources. The base station can instruct the UE that CSI-RS resources in the CSI-RS resource set are activated and / or deactivated.

[0138] The base station can configure the UE to report CSI measurements. The base station can configure the UE to provide CSI reports periodically, aperiodically, or semi-persistently. For periodic CSI reporting, the UE can be configured with multiple CSI report timings and / or periods. For aperiodic CSI reporting, the base station can request CSI reports. For example, the base station can command the UE to measure configured CSI-RS resources and provide CSI reports related to the measurements. For semi-persistent CSI reporting, the base station can configure the UE to transmit periodically and selectively activate or deactivate periodic reports. The base station can configure the UE using CSI-RS resource sets and CSI reports using RRC signaling.

[0139] The CSI-RS configuration may include one or more parameters indicating, for example, up to 32 antenna ports. The UE can be configured to use the same OFDM symbols for both the downlink CSI-RS and the control resource set (CORESET) when the downlink CSI-RS and CORESET are spatially QCLed and the resource elements associated with the downlink CSI-RS are outside the physical resource block (PRB) configured for the CORESET. The UE can also be configured to use the same OFDM symbols for both the downlink CSI-RS and the SS / PBCH block when the downlink CSI-RS and SS / PBCH blocks are spatially QCLed and the resource elements associated with the downlink CSI-RS are outside the PRB configured for the SS / PBCH block.

[0140] Downlink DMRS can be transmitted by the base station and used by the UE for channel estimation. For example, downlink DMRS can be used for consistent demodulation of one or more downlink physical channels (e.g., PDSCH). The NR network can support one or more variable and / or configurable DMRS modes for data demodulation. At least one downlink DMRS configuration can support a frontload DMRS mode. Frontload DMRS can be mapped on the one or more OFDM symbols (e.g., one or two adjacent OFDM symbols). The base station can semi-statically configure the UE using the number (e.g., maximum number) of frontload DMRS symbols used for PDSCH. A DMRS configuration can support one or more DMRS ports. For example, for single-user MIMO, a DMRS configuration can support up to eight orthogonal downlink DMRS ports per UE. For multi-user MIMO, a DMRS configuration can support up to four orthogonal downlink DMRS ports per UE. The radio network can (e.g., at least for CP-OFDM) support a common DMRS structure for downlink and uplink, where DMRS locations, DMRS types, and / or scrambling sequences can be the same or different. The base station can use the same precoding matrix to transmit downlink DMRS and the corresponding PDSCH. The UE can use one or more downlink DMRS to perform consistent demodulation / channel estimation of the PDSCH.

[0141] In the example, the transmitter (e.g., a base station) can use a precoder matrix for a portion of the transmission bandwidth. For example, the transmitter can use a first precoder matrix for a first bandwidth and a second precoder matrix for a second bandwidth. The first and second precoder matrices can differ based on the first and second bandwidths being different. The UE can assume that the same precoder matrix is ​​used across the set of PRBs. The set of PRBs can be represented as a Precode Resource Block Group (PRG).

[0142] A PDSCH can contain one or more layers. The UE can assume that at least one symbol with DMRS exists on one or more layers of the PDSCH. A higher layer can configure up to three DMRS for the PDSCH.

[0143] Downlink PT-RS can be transmitted by the base station and used by the UE for phase noise compensation. The presence of downlink PT-RS can depend on RRC configuration. The presence and / or type of downlink PT-RS can be configured UE-specifically using a combination of RRC signaling and / or association with one or more parameters (e.g., modulation and coding scheme (MCS)) indicated by the DCI for other purposes. When configured, the dynamic presence of downlink PT-RS can be associated with one or more DCI parameters containing at least one MCS. NR networks can support multiple PT-RS densities defined in the time and / or frequency domains. When present, the frequency domain density can be associated with at least one configuration of the scheduled bandwidth. The UE can employ the same precoding for both DMRS ports and PT-RS ports. The number of PT-RS ports can be less than the number of DMRS ports in the scheduled resources. Downlink PT-RS can be restricted to the UE's scheduled time / frequency duration. Downlink PT-RS can be transmitted on symbols to facilitate phase tracking at the receiver.

[0144] The UE can transmit uplink DMRS to the base station for channel estimation. For example, the base station can use uplink DMRS to perform consistent demodulation of one or more uplink physical channels. For example, the UE can transmit uplink DMRS with PUSCH and / or PUCCH. Uplink DMRS can span a frequency range similar to the frequency range associated with the corresponding physical channel. The base station can configure the UE using one or more uplink DMRS configurations. At least one DMRS configuration can support a frontload DMRS mode. Frontload DMRS can be mapped on one or more OFDM symbols (e.g., one or two adjacent OFDM symbols). One or more uplink DMRS can be configured to be transmitted at one or more symbols of PUSCH and / or PUCCH. The base station can semi-statically configure the UE with the number (e.g., maximum number) of frontload DMRS symbols of PUSCH and / or PUCCH, which the UE can use to schedule single-symbol DMRS and / or dual-symbol DMRS. NR networks can support (e.g., for Cyclic Prefix Orthogonal Frequency Division Multiplexing (CP-OFDM)) a common DMRS structure for both downlink and uplink, where the DMRS location, DMRS type and / or scrambling sequence of the DMRS can be the same or different.

[0145] A PUSCH can contain one or more layers, and a UE can transmit at least one symbol with DMRS present on one or more layers of the PUSCH. In the example, a higher layer can configure up to three DMRS for the PUSCH.

[0146] Depending on the UE's RRC configuration, the uplink PT-RS (which can be used by the base station for phase tracking and / or phase noise compensation) may or may not be present. The presence and / or type of the uplink PT-RS can be configured UE-specifically through a combination of RRC signaling and / or through one or more parameters indicated by the DCI for other purposes (e.g., modulation and coding scheme (MCS)). When configured, the dynamic presence of the uplink PT-RS can be associated with one or more DCI parameters that include at least one MCS. The radio network can support multiple uplink PT-RS densities defined in the time / frequency domain. When present, the frequency domain density can be associated with at least one configuration of the scheduled bandwidth. The UE can use the same precoding for both DMRS ports and PT-RS ports. The number of PT-RS ports can be less than the number of DMRS ports in the scheduled resources. For example, the uplink PT-RS can be limited to the duration of the UE's scheduled time / frequency.

[0147] The UE can transmit SRS to the base station for channel state estimation to support uplink channel-dependent scheduling and / or link adaptation. The SRS transmitted by the UE allows the base station to estimate the uplink channel state at one or more frequencies. The scheduler at the base station can use the estimated uplink channel state to assign one or more resource blocks to uplink PUSCH transmissions from the UE. The base station can semi-statically configure the UE using one or more SRS resource sets. For each SRS resource set, the base station can configure the UE using one or more SRS resources. SRS resource set suitability can be configured by higher-layer (e.g., RRC) parameters. For example, when higher-layer parameters indicate beam management, SRS resources in one or more SRS resource sets (e.g., having the same / similar time-domain behavior, periodic, aperiodic, etc.) can be transmitted at some point (e.g., simultaneously). The UE can transmit one or more SRS resources from the SRS resource set. The NR network can support aperiodic, periodic, and / or semi-persistent SRS transmissions. The UE can transmit SRS resources based on one or more trigger types, wherein the one or more trigger types may include higher-layer signaling (e.g., RRC) and / or one or more DCI formats. In the example, at least one DCI format may be used for the UE to select at least one configured SRS resource set from one or more configured SRS resource sets. SRS trigger type 0 may refer to SRS triggered based on higher-layer signaling. SRS trigger type 1 may refer to SRS triggered based on one or more DCI formats. In the example, when PUSCH and SRS are transmitted in the same time slot, the UE can be configured to transmit SRS after the transmission of PUSCH and the corresponding uplink DMRS.

[0148] The base station can semi-statically configure the UE using one or more SRS configuration parameters indicating at least one of the following: SRS resource configuration identifier; number of SRS ports; temporal behavior of SRS resource configuration (e.g., indication of periodic, semi-persistent, or aperiodic SRS); time slot, micro-time slot, and / or subframe level periodicity; offset of periodic and / or aperiodic SRS resources; number of OFDM symbols in SRS resources; initiation OFDM symbols for SRS resources; SRS bandwidth; frequency hopping bandwidth; cyclic shift; and / or SRS sequence ID.

[0149] Antenna ports are defined such that a symbol on an antenna port, through the channel through which it is transmitted, can be inferred from another symbol on the same antenna port through the same channel. If a first symbol and a second symbol are transmitted on the same antenna port, a receiver can infer the channel used to transmit the second symbol on the antenna port (e.g., fading gain, multipath delay, etc.) from the channel used to transmit the first symbol on the antenna port. A first antenna port and a second antenna port can be referred to as quasi-co-located (QCLed) if one or more large-scale properties can be inferred from the channel through which the second symbol on the second antenna port is transmitted, and the channel through which the first symbol on the first antenna port is transmitted. The one or more large-scale properties may include at least one of the following: delay spread; Doppler spread; Doppler shift; average gain; average delay; and / or spatial reception (Rx) parameters.

[0150] Channels using beamforming require beam management. Beam management can include beam measurement, beam selection, and beam indication. A beam can be associated with one or more reference signals. For example, a beam can be identified by one or more beamforming reference signals. The UE can perform downlink beam measurements and generate a beam measurement report based on downlink reference signals (e.g., Channel State Information Reference Signal (CSI-RS)). After establishing an RRC connection with the base station, the UE can perform the downlink beam measurement procedure.

[0151] Figure 11B illustrates an example of a Channel State Information Reference Signal (CSI-RS) mapped in the time and frequency domains. The squares shown in Figure 11B can represent resource blocks (RBs) within the cell's bandwidth. The base station can transmit one or more RRC messages containing CSI-RS resource configuration parameters indicating one or more CSI-RSs. One or more of the following parameters can be configured for CSI-RS resource configuration via higher-level signaling (e.g., RRC and / or MAC signaling): CSI-RS resource configuration identity, number of CSI-RS ports, CSI-RS configuration (e.g., symbol and resource element (RE) positions in subframes), CSI-RS subframe configuration (e.g., subframe positions, offsets, and periodicity in radio frames), CSI-RS power parameters, CSI-RS sequence parameters, code division multiplexing (CDM) type parameters, frequency density, transmission comb, quasi-co-address (QCL) parameters (e.g., QCL-scramblingidentity, crs-portscount, mbsfn-subframeconfiglist, csi-rs-configZPid, qcl-csi-rs-configNZPid), and / or other radio resource parameters.

[0152] The three beams shown in Figure 11B can be configured for a UE in a UE-specific configuration. Figure 11B shows three beams (beam #1, beam #2, and beam #3), and more or fewer beams can be configured. CSI-RS1101 can be assigned to beam #1, which can be transmitted on one or more subcarriers in the RB of the first symbol. CSI-RS1102 can be assigned to beam #2, which can be transmitted on one or more subcarriers in the RB of the second symbol. CSI-RS1103 can be assigned to beam #3, which can be transmitted on one or more subcarriers in the RB of the third symbol. By using frequency division multiplexing (FDM), the base station can use other subcarriers in the same RB (e.g., those not used to transmit CSI-RS 1101) to transmit another CSI-RS associated with a beam of another UE. By using time domain multiplexing (TDM), the beams for a UE can be configured such that the beams for a UE use symbols from beams of other UEs.

[0153] CSI-RS, such as those shown in Figure 11B (e.g., CSI-RS 1101, 1102, 1103), can be transmitted by the base station and used by the UE for one or more measurements. For example, the UE can measure the Reference Signal Received Power (RSRP) configured with CSI-RS resources. The base station can configure the UE using a reporting configuration, and the UE can report RSRP measurements to the network based on the reporting configuration (e.g., via one or more base stations). In the example, the base station can determine one or more Transmission Configuration Indication (TCI) states containing multiple reference signals based on the reported measurement results. In the example, the base station can indicate one or more TCI states to the UE (e.g., via RRC signaling, MAC CE, and / or DCI). The UE can receive downlink transmissions with a receive (Rx) beam determined based on the one or more TCI states. In the example, the UE may or may not have beam correspondence capability. If the UE has beam correspondence capability, the UE can determine the spatial domain filter for the transmit (Tx) beam based on the spatial domain filter corresponding to the Rx beam. If the UE does not have beam correspondence capability, the UE can perform an uplink beam selection procedure to determine the spatial domain filter for the Tx beam. The UE can perform the uplink beam selection procedure based on one or more Sounding Reference Signal (SRS) resources configured for the UE by the base station. The base station can select and indicate the UE's uplink beam based on measurements of one or more SRS resources transmitted by the UE.

[0154] In the beam management procedure, the UE can assess (e.g., measure) the channel quality of one or more beampup links, beampup links containing transmit beams transmitted by the base station, and receive beams received by the UE. Based on the assessment, the UE can transmit a beam measurement report indicating one or more beampup quality parameters, which include, for example, one or more beam identifiers (e.g., beam index, reference signal index, etc.), RSRP, precoding matrix indicator (PMI), channel quality indicator (CQI), and / or rank indicator (RI).

[0155] Figure 12A illustrates examples of three downlink beam management procedures: P1, P2, and P3. Procedure P1 can enable UE measurement of the transmission (Tx) beams for a Transport Receiver Point (TRP) (or multiple TRPs), for example, to support the selection of one or more base station Tx beams and / or UE Rx beams (shown as ellipses in the top and bottom rows of P1, respectively). Beamforming at the TRP can include Tx beam sweeping for the beam set (shown as ellipses rotating counterclockwise in the top rows of P1 and P2, indicated by dashed arrows). Beamforming at the UE can include Rx beam sweeping for the beam set (shown as ellipses rotating clockwise in the bottom rows of P1 and P3, indicated by dashed arrows). Procedure P2 can be used to enable UE measurement of the Tx beams for a TRP (shown as ellipses rotating counterclockwise in the top row of P2, indicated by dashed arrows). The UE and / or base station may perform procedure P2 using a smaller beam set than that used in procedure P1, or using a narrower beam than that used in procedure P1. This may be referred to as beam refinement. The UE may perform procedure P3 for Rx beam determination by using the same Tx beam at the base station and sweeping the Rx beam at the UE.

[0156] Figure 12B illustrates examples of three uplink beam management procedures: U1, U2, and U3. Procedure U1 can be used to enable the base station to perform measurements on the UE's Tx beam, for example, to support the selection of one or more UE Tx beams and / or base station Rx beams (shown as ellipses in the top and bottom rows of U1, respectively). Beamforming at the UE can include, for example, a Tx beam sweep from the set of beams (shown as an ellipse rotating clockwise in the bottom rows of U1 and U3, indicated by the dashed arrows). Beamforming at the base station can include, for example, an Rx beam sweep from the set of beams (shown as an ellipse rotating counterclockwise in the top rows of U1 and U2, indicated by the dashed arrows). When the UE uses a fixed Tx beam, procedure U2 can be used to enable the base station to adjust its Rx beam. The UE and / or base station may execute procedure U2 using a smaller beam set than that used in procedure P1, or using a narrower beam than that used in procedure P1. This may be referred to as beam refinement. The UE may execute procedure U3 to adjust its Tx beam when the base station uses a fixed Rx beam.

[0157] The UE can initiate a beam failure recovery (BFR) procedure based on the detection of a beam failure. The UE can initiate a BFR procedure by transmitting a BFR request (e.g., preamble, UCI, SR, MAC CE, etc.). The UE can detect a beam failure based on the determination that the quality of the beam pair link in the associated control channel is unsatisfactory (e.g., an error rate higher than the error rate threshold, received signal power lower than the received signal power threshold, timer expiration, etc.).

[0158] The UE can use one or more reference signals (RS) to measure the quality of the beamp-link, said one or more reference signals comprising one or more SS / PBCH blocks, one or more CSI-RS resources, and / or one or more demodulation reference signals (DMRS). The quality of the beamp-link can be based on one or more of the following: block error rate (BLER), RSRP value, signal-to-interference-plus-noise ratio (SINR) value, reference signal reception quality (RSRQ) value, and / or CSI value measured on the RS resources. The base station can indicate one or more DM-RS quasi-co-located (QCLed) RS resources and channels (e.g., control channels, shared data channels, etc.). The one or more DMRS of the RS resources and channels can be QCLed when the channel characteristics (e.g., Doppler shift, Doppler spread, average delay, delay spread, spatial Rx parameter, fading, etc.) from transmissions to the UE via the RS resources are similar to or the same as the channel characteristics from transmissions to the UE via the channels.

[0159] The network (e.g., gNB and / or the network's ng-eNB) and / or the UE can initiate a random access procedure. A UE in the RRC_IDLE state and / or RRC_INACTIVE state can initiate a random access procedure to request connection settings to the network. A UE can initiate a random access procedure from the RRC_CONNECTED state. A UE can initiate a random access procedure to request uplink resources (e.g., for uplink transmission of SR when no PUCCH resources are available) and / or to acquire uplink timing (e.g., when the uplink synchronization state is not synchronized). A UE can initiate a random access procedure to request one or more System Information Blocks (SIBs) (e.g., other system information such as SIB2, SIB3, etc.). A UE can initiate a random access procedure for beam failure recovery requests. The network can initiate random access procedures for handover and / or for establishing time alignment for SCell additions.

[0160] Figure 13A illustrates a four-step contention-based random access procedure. Before initiating the procedure, the base station may transmit configuration message 1310 to the UE. The procedure shown in Figure 13A involves the transmission of four messages: Msg 1 1311, Msg 2 1312, Msg 3 1313, and Msg 4 1314. Msg 1 1311 may include and / or be referred to as a preamble (or random access preamble). Msg 2 1312 may include and / or be referred to as a random access response (RAR).

[0161] Configuration message 1310 may be transmitted, for example, using one or more RRC messages. These one or more RRC messages may indicate one or more Random Access Channel (RACH) parameters to the UE. The one or more RACH parameters may include at least one of the following: general parameters for one or more random access procedures (e.g., RACH-configGeneral); cell-specific parameters (e.g., RACH-ConfigCommon); and / or dedicated parameters (e.g., RACH-configDedicated). The base station may broadcast or multicast the one or more RRC messages to one or more UEs. The one or more RRC messages may be UE-specific (e.g., dedicated RRC messages transmitted to the UE in the RRC_CONNECTED state and / or RRC_INACTIVE state). The UE may determine the time-frequency resources and / or uplink transmission power for transmitting Msg 11311 and / or Msg 3 1313 based on the one or more RACH parameters. Based on the one or more RACH parameters, the UE may determine the receive timing and downlink channel for receiving Msg 2 1312 and Msg 4 1314.

[0162] The one or more RACH parameters provided in configuration message 1310 may indicate one or more physical RACH (PRACH) timings available for transmitting Msg 11311. These one or more PRACH timings may be predefined. The one or more RACH parameters may indicate one or more available sets of one or more PRACH timings (e.g., prach-ConfigIndex). The one or more RACH parameters may indicate an association between (a) one or more PRACH timings and (b) one or more reference signals. The one or more RACH parameters may indicate an association between (a) one or more preambles and (b) one or more reference signals. The one or more reference signals may be SS / PBCH blocks and / or CSI-RS. For example, the one or more RACH parameters may indicate the number of SS / PBCH blocks mapped to PRACH timings and / or the number of preambles mapped to SS / PBCH blocks.

[0163] The one or more RACH parameters provided in configuration message 1310 can be used to determine the uplink transmission power of Msg 1 1311 and / or Msg 3 1313. For example, the one or more RACH parameters can indicate a reference power for preamble transmission (e.g., the received target power and / or the initial power of the preamble transmission). One or more power offsets indicated by the one or more RACH parameters may exist. For example, the one or more RACH parameters can indicate: power ramp step size; power offset between SSB and CSI-RS; power offset between transmissions of Msg 1 1311 and Msg 3 1313; and / or power offset values ​​between preamble groups. The one or more RACH parameters can indicate one or more thresholds upon which the UE can determine at least one reference signal (e.g., SSB and / or CSI-RS) and / or uplink carrier (e.g., normal uplink (NUL) carrier and / or supplementary uplink (SUL) carrier).

[0164] Msg 1 1311 may include one or more preamble transmissions (e.g., preamble transmission and one or more preamble retransmissions). RRC messages can be used to configure one or more preamble groups (e.g., group A and / or group B). A preamble group may contain one or more preambles. The UE may determine the preamble group based on path loss measurements and / or the magnitude of Msg 3 1313. The UE may measure the RSRP of one or more reference signals (e.g., SSB and / or CSI-RS) and determine at least one reference signal with an RSRP higher than an RSRP threshold (e.g., rsrp-ThresholdSSB and / or rsrp-ThresholdCSI-RS). For example, if the association between the one or more preambles and the at least one reference signal is configured by an RRC message, the UE can select at least one preamble associated with the one or more reference signals and / or the selected preamble group.

[0165] The UE can determine the preamble based on one or more RACH parameters provided in configuration message 1310. For example, the UE can determine the preamble based on path loss measurement, RSRP measurement, and / or the size of Msg 3 1313. As another example, the one or more RACH parameters can indicate: the preamble format; the maximum number of preamble transmissions; and / or one or more thresholds for determining one or more preamble groups (e.g., group A and group B). The base station can use the one or more RACH parameters to configure an association between one or more preambles and one or more reference signals (e.g., SSB and / or CSI-RS) for the UE. If the association is configured, the UE can determine the preamble included in Msg 1 1311 based on the association. Msg 1 1311 can be transmitted to the base station via one or more PRACH timings. The UE can use one or more reference signals (e.g., SSB and / or CSI-RS) for selecting the preamble and for determining the PRACH timing. One or more RACH parameters (e.g., ra-ssb-OccasionMskIndex and / or ra-OccasionList) can indicate the association between the PRACH timing and the one or more reference signals.

[0166] If no response is received after the preamble transmission, the UE may perform a preamble retransmission. The UE may increase the uplink transmission power used for the preamble retransmission. The UE may select the initial preamble transmission power based on path loss measurements and / or the preamble power received by the target as configured by the network. The UE may determine the preamble to be retransmitted and may ramp up the uplink transmission power. The UE may receive one or more RACH parameters (e.g., PREAMBLE_POWER_RAMPING_STEP) indicating the ramp step size used for the preamble retransmission. The ramp step size may be the amount by which the uplink transmission power used for the retransmission is incrementally increased. If the UE determines that the same reference signal (e.g., SSB and / or CSI-RS) is used as in the previous preamble transmission, the UE may ramp up the uplink transmission power. The UE may count the number of preamble transmissions and / or retransmissions (e.g., PREAMBLE_TRANSMISSION_COUNTER). For example, if the number of preamble transmissions exceeds a threshold configured by one or more RACH parameters (e.g., preambleTransMax), the UE can determine that the random access procedure has not been successfully completed.

[0167] The Msg 2 1312 received by the UE may include a RAR. In some scenarios, Msg 2 1312 may include multiple RARs corresponding to multiple UEs. Msg 2 1312 may be received after or in response to the transmission of Msg 1 1311. Msg 2 1312 may be scheduled on the DL-SCH and indicated on the PDCCH using a Random Access RNTI (RA-RNTI). Msg 2 1312 may indicate that Msg 1 1311 was received by the base station. Msg 2 1312 may include a time comparison command that the UE can use to adjust the UE's transmission timing, a scheduling permission for transmitting Msg 3 1313, and / or a Temporary Cell RNTI (TC-RNTI). After transmitting the preamble, the UE may initiate a time window (e.g., ra-ResponseWindow) to monitor the PDCCH for Msg 2 1312. The UE can determine when to initiate a time window based on the PRACH timing in which it transmits the preamble. For example, the UE can initiate a time window for one or more symbols after the last symbol of the preamble (e.g., at the first PDCCH timing starting from the end of the preamble transmission). The one or more symbols can be determined based on a set of parameters. The PDCCH can be in a common search space configured by RRC messages (e.g., a Type 1-PDCCH common search space). The UE can identify the RAR based on a Radio Network Temporary Identifier (RNTI). The RNTI can be used depending on one or more events that initiate a random access procedure. The UE can use a Random Access RNTI (RA-RNTI). The RA-RNTI can be associated with the PRACH timing in which the UE transmits the preamble. For example, the UE can determine the RA-RNTI based on: the OFDM symbol index; the time slot index; the frequency domain index; and / or the UL carrier indicator of the PRACH timing. An example of RA-RNTI can be as follows: RA-RNTI = 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × 8 × ul_carrier_id, where s_id can be the index of the first OFDM symbol of the PRACH timing (e.g., 0 ≤ s_id < 14), t_id can be the index of the first slot of the PRACH timing in the system frame (e.g., 0 ≤ t_id < 80), f_id can be the index of the PRACH timing in the frequency domain (e.g., 0 ≤ f_id < 8), and ul_carrier_id can be the UL carrier used for preamble transmission (e.g., 0 for NUL carriers and 1 for SUL carriers).

[0168] The UE may transmit Msg 3 1313 in response to successful reception of Msg 2 1312 (e.g., using the resource identified in Msg 2 1312). Msg 3 1313 can be used for contention resolution in a contention-based random access procedure, such as that shown in Figure 13A. In some scenarios, multiple UEs may transmit the same preamble to the base station, and the base station may provide a RAR corresponding to each UE. If the multiple UEs interpret the RAR as corresponding to themselves, a conflict may occur. Contention resolution (e.g., using Msg 3 1313 and Msg 4 1314) can be used to increase the likelihood that a UE does not mistakenly use the identity of another UE. To perform contention resolution, the UE may include a device identifier in Msg 3 1313 (e.g., the TC-RNTI included in Msg 2 1312 if a C-RNTI is assigned and / or any other suitable identifier).

[0169] Msg 4 1314 can be received after or in response to the transmission of Msg 3 1313. If Msg 3 1313 includes a C-RNTI, the base station will use the C-RNTI to address the UE on the PDCCH. If the UE's unique C-RNTI is detected on the PDCCH, the random access procedure is determined to have been successfully completed. If Msg 3 1313 includes a TC-RNTI (e.g., if the UE is in an RRC_IDLE state or not otherwise connected to the base station), Msg 4 1314 will be received using the DL-SCH associated with the TC-RNTI. If the MAC PDU is successfully decoded and the MAC PDU contains a UE contention resolution identity MAC CE that matches (e.g., is transmitted) the CCCH SDU sent in Msg 3 1313, the UE can determine that contention resolution was successful and / or the UE can determine that the random access procedure was successfully completed.

[0170] The UE can be configured with Supplemental Uplink (SUL) carriers and Normal Uplink (NUL) carriers. Initial access (e.g., random access procedure) can be supported on the uplink carriers. For example, the base station can configure two separate RACH configurations for the UE: one for the SUL carrier and another for the NUL carrier. To enable random access in a cell configured with an SUL carrier, the network can indicate which carrier (NUL or SUL) to use. For example, the UE can determine the SUL carrier if the measured quality of one or more reference signals is below a broadcast threshold. Uplink transmissions during the random access procedure (e.g., Msg 1 1311 and / or Msg 3 1313) can be preserved on the selected carrier. In one or more cases, the UE can switch uplink carriers during the random access procedure (e.g., between Msg 1 1311 and Msg 3 1313). For example, the UE can determine and / or switch uplink carriers for Msg 1 1311 and / or Msg 3 1313 based on channel clarity assessment (e.g., listen before speaking).

[0171] Figure 13B illustrates a two-step contention-free random access procedure. Similar to the four-step contention-based random access procedure shown in Figure 13A, the base station may transmit configuration message 1320 to the UE before the procedure is initiated. Configuration message 1320 may be similar to configuration message 1310 in some respects. The procedure shown in Figure 13B involves the transmission of two messages: Msg 1 1321 and Msg 2 1322. Msg 1 1321 and Msg 2 1322 may be similar to Msg 1 1311 and Msg2 1312 shown in Figure 13A, respectively. As will be understood from Figures 13A and 13B, a contention-free random access procedure may not include messages similar to Msg 3 1313 and / or Msg 4 1314.

[0172] The contention-free random access procedure shown in Figure 13B can be initiated for beam failure recovery, other SI requests, SCell addition and / or handover. For example, the base station can indicate or assign a preamble to the UE for Msg 1 1321. The UE can receive the preamble indication (e.g., ra-PreambleIndex) from the base station via PDCCH and / or RRC.

[0173] After transmitting the preamble, the UE can initiate a time window (e.g., ra-ResponseWindow) to monitor the PDCCH of the RAR. In the event of a beam failure recovery request, the base station can configure the UE with a separate time window and / or a separate PDCCH in the search space indicated by the RRC message (e.g., recoverySearchSpaceId). The UE can monitor the PDCCH transmission addressed to the Cell RNTI (C-RNTI) in the search space. In the contention-free random access procedure shown in Figure 13B, the UE can determine that the random access procedure was successfully completed after or in response to the transmission of Msg 1 1321 and the reception of the corresponding Msg 2 1322. For example, if the PDCCH transmission addresses to the C-RNTI, the UE can determine that the random access procedure was successfully completed. For example, if the UE receives a RAR containing a preamble identifier corresponding to the preamble transmitted by the UE and / or the RAR contains a MAC subPDU with a preamble identifier, the UE can determine that the random access procedure was successfully completed. The UE can determine that the response is an indication of confirmation of the SI request.

[0174] Figure 13C illustrates another two-step random access procedure. Similar to the random access procedures shown in Figures 13A and 13B, the base station may transmit configuration message 1330 to the UE before the procedure is initiated. Configuration message 1330 may be similar in some respects to configuration messages 1310 and / or 1320. The procedure shown in Figure 13C involves the transmission of two messages: Msg A 1331 and Msg B 1332.

[0175] Msg A 1331 can be transmitted by the UE in an uplink transmission. Msg A 1331 may contain one or more transmissions of preamble 1341 and / or one or more transmissions of transport block 1342. Transport block 1342 may contain content similar to and / or equivalent to the content of Msg 3 1313 shown in FIG. 13A. Transport block 1342 may contain UCIs (e.g., SR, HARQ ACK / NACK, etc.). The UE may receive Msg B 1332 after transmitting Msg A 1331 or in response to said transmission. Msg B 1332 may contain content similar to and / or equivalent to the content of Msg 2 1312 (e.g., RAR) shown in FIG. 13A and FIG. 13B and / or Msg 4 1314 shown in FIG. 13A.

[0176] The UE can initiate the two-step random access procedure shown in Figure 13C for licensed and / or unlicensed spectrum. The UE can determine whether to initiate the two-step random access procedure based on one or more factors. The one or more factors may be: the radio access technology being used (e.g., LTE, NR, etc.); whether the UE has a valid TA; cell size; the UE's RRC status; the type of spectrum (e.g., licensed vs. unlicensed); and / or any other suitable factors.

[0177] The UE can determine the radio resources and / or uplink transmission power of the preamble 1341 and / or transport block 1342 included in Msg A 1331 based on the two-step RACH parameters included in configuration message 1330. The RACH parameters can indicate the modulation and coding scheme (MCS), time-frequency resources, and / or power control of the preamble 1341 and / or transport block 1342. The time-frequency resources (e.g., PRACH) for the transmission of the preamble 1341 and the time-frequency resources (e.g., PUSCH) for the transmission of the transport block 1342 can be multiplexed using FDM, TDM, and / or CDM. The RACH parameters enable the UE to determine the receive timing and downlink channel for monitoring and / or receiving Msg B 1332.

[0178] Transport block 1342 may contain data (e.g., delay-sensitive data), a UE identifier, security information, and / or device information (e.g., International Mobile Subscriber Identity (IMSI)). The base station may transmit Msg B 1332 as a response to Msg A 1331. Msg B 1332 may contain at least one of the following: a preamble identifier; a timing advanced command; a power control command; uplink grant (e.g., radio resource allocation and / or MCS); a UE identifier for contention resolution; and / or an RNTI (e.g., a C-RNTI or a TC-RNTI). The UE can determine that the two-step random access procedure was successfully completed if: the preamble identifier in Msg B 1332 matches the preamble transmitted by the UE; and / or the UE identifier in Msg B 1332 matches the UE identifier in Msg A 1331 (e.g., transport block 1342).

[0179] The UE and the base station can exchange control signaling. The control signaling may be referred to as L1 / L2 control signaling and may originate from the PHY layer (e.g., Layer 1) and / or the MAC layer (e.g., Layer 2). The control signaling may include downlink control signaling transmitted from the base station to the UE and / or uplink control signaling transmitted from the UE to the base station.

[0180] Downlink control signaling may include: downlink scheduling assignment; uplink scheduling permission indicating uplink radio resources and / or transmission format; time slot format information; preemption indication; power control command; and / or any other suitable signaling. The UE may receive downlink control signaling in the payload transmitted by the base station on the Physical Downlink Control Channel (PDCCH). The payload transmitted on the PDCCH may be referred to as Downlink Control Information (DCI). In some scenarios, the PDCCH may be a group-shared PDCCH (GC-PDCCH) common to the UE group.

[0181] A base station can attach one or more Cyclic Redundancy Check (CRC) parity bits to the DCI to aid in the detection of transmission errors. When the DCI is intended for use with a UE (or a group of UEs), the base station can scramble the CRC parity bits with the UE's identifier (or the UE group's identifier). Scrambling the CRC parity bits with the identifier can involve a modulo-2 addition (or XOR operation) of the identifier value and the CRC parity bits. The identifier can contain a 16-bit value of the Radio Network Temporary Identifier (RNTI).

[0182] DCIs can be used for various purposes. The purpose can be indicated by the type of RNTI used to scramble the CRC parity bits. For example, a DCI with CRC parity bits scrambled using a paging RNTI (P-RNTI) can indicate paging information and / or system information change notifications. A P-RNTI can be predefined as "FFFE" in hexadecimal. A DCI with CRC parity bits scrambled using a system information RNTI (SI-RNTI) can indicate broadcast transmission of system information. A SI-RNTI can be predefined as "FFFF" in hexadecimal. A DCI with CRC parity bits scrambled using a random access RNTI (RA-RNTI) can indicate a random access response (RAR). A DCI with CRC parity bits scrambled using a cell RNTI (C-RNTI) can indicate dynamically scheduled unicast transmissions and / or triggering of PDCCH ordered random access. A DCI with CRC parity bits scrambled using a Temporary Cell RNTI (TC-RNTI) can indicate contention resolution (e.g., Msg 3 similar to Msg 3 1313 shown in Figure 13A). Other RNTIs configured by the base station for the UE may include: the configured scheduling RNTI (CS-RNTI), the transmission power control PUCCH RNTI (TPC-PUCCH-RNTI), the transmission power control PUSCH RNTI (TPC-PUSCH-RNTI), the transmission power control SRS RNTI (TPC-SRS-RNTI), the interrupt RNTI (INT-RNTI), the slot format indication RNTI (SFI-RNTI), the semi-persistent CSI RNTI (SP-CSI-RNTI), the modulation and coding scheme cell RNTI (MCS-C-RNTI), and so on.

[0183] Depending on the purpose and / or content of the DCI, the base station may transmit DCI with one or more DCI formats. For example, DCI format 0_0 can be used for PUSCH scheduling in a cell. DCI format 0_0 can be a fallback DCI format (e.g., with a compact DCI payload). DCI format 0_1 ​​can be used for PUSCH scheduling in a cell (e.g., with a larger DCI payload than DCI format 0_0). DCI format 1_0 can be used for PDSCH scheduling in a cell. DCI format 1_0 can be a fallback DCI format (e.g., with a compact DCI payload). DCI format 1_1 can be used for PDSCH scheduling in a cell (e.g., with a larger DCI payload than DCI format 1_0). DCI format 2_0 can be used to provide slot format indication to UE groups. DCI format 2_1 can be used to notify UE groups of physical resource blocks and / or OFDM symbols, where UEs may assume that transmission to UEs is not expected. DCI format 2_2 can be used to transmit Transmission Power Control (TPC) commands for PUCCH or PUSCH. DCI format 2_3 can be used to transmit TPC command groups for SRS transmission by one or more UEs. New DCI formats for new features can be defined in future versions. DCI formats can have different DCI sizes, or they can share the same DCI size.

[0184] After scrambling the DCI with RNTI, the base station can process the DCI using channel coding (e.g., polarity coding), rate matching, scrambling, and / or QPSK modulation. The base station can map the coded and modulated DCI onto resource elements used for and / or configured for the PDCCH. Based on the DCI payload size and / or the base station's coverage area, the base station can transmit the DCI via a PDCCH occupying multiple consecutive control channel elements (CCEs). The number of consecutive CCEs (referred to as the aggregation level) can be 1, 2, 4, 8, 16, and / or any other suitable number. A CCE can contain a number of resource element groups (REGs) (e.g., 6). A REG can contain resource blocks in OFDM symbols. The mapping of the coded and modulated DCI onto resource elements can be based on a mapping between CCEs and REGs (e.g., CCE-to-REG mapping).

[0185] Figure 14A illustrates an example of a CORESET configuration for the bandwidth portion. A base station can transmit DCI via PDCCH on one or more control resource sets (CORESETs). A CORESET can contain time-frequency resources in which the UE attempts to decode the DCI using one or more search spaces. The base station can configure CORESETs in the time-frequency domain. In the example of Figure 14A, the first CORESET 1401 and the second CORESET 1402 appear at the first symbol of the time slot. The first CORESET 1401 overlaps with the second CORESET 1402 in the frequency domain. The third CORESET 1403 appears at the third symbol of the time slot. The fourth CORESET 1404 appears at the seventh symbol of the time slot. CORESETs can have different numbers of resource blocks in the frequency domain.

[0186] Figure 14B illustrates an example of CCE-to-REG mapping for DCI transmission in CORESET and PDCCH processing. CCE-to-REG mapping can be interleaved (e.g., for providing frequency diversity) or non-interleaved (e.g., for facilitating interference coordination and / or frequency-selective transmission in the control channel). The base station can perform different or the same CCE-to-REG mappings for different CORESETs. A CORESET can be associated with CCE-to-REG mapping via RRC configuration. A CORESET can be configured with antenna port quasi-co-location (QCL) parameters. Antenna port QCL parameters can indicate the QCL information for the demodulation reference signal (DMRS) used for PDCCH reception in the CORESET.

[0187] The base station can transmit an RRC message to the UE containing configuration parameters for one or more CORESETs and one or more search space sets. The configuration parameters can indicate the association between the search space set and the CORESET. The search space set can contain a set of PDCCH candidates formed by CCEs at a given aggregation level. The configuration parameters can indicate: the number of PDCCH candidates to be monitored at each aggregation level; the PDCCH monitoring period and PDCCH monitoring type; one or more DCI formats to be monitored by the UE; and / or whether the search space set is a common search space set or a UE-specific search space set. The set of CCEs in the common search space set can be predefined and known to the UE. The set of CCEs in the UE-specific search space set can be configured based on the UE's identifier (e.g., C-RNTI).

[0188] As shown in Figure 14B, the UE can determine the time-frequency resources of the CORESET based on RRC messages. The UE can determine the CCE-to-REG mapping of the CORESET (e.g., interleaved or non-interleaved and / or mapping parameters) based on the CORESET's configuration parameters. The UE can determine the number of search space sets configured on the CORESET (e.g., up to 10) based on RRC messages. The UE can monitor a set of PDCCH candidates based on the configuration parameters of the search space sets. The UE can monitor a set of PDCCH candidates in one or more CORESETs for detecting one or more DCIs. Monitoring may include decoding one or more PDCCH candidates in the set of PDCCH candidates according to the monitored DCI format. Monitoring may include decoding the DCI content of one or more PDCCH candidates, which have possible (or configured) PDCCH locations, possible (or configured) PDCCH formats (e.g., the number of CCEs, the number of PDCCH candidates in the common search space, and / or the number of PDCCH candidates in the UE-specific search space), and possible (or configured) DCI formats. Decoding may be referred to as blind decoding. The UE can determine that the DCI is valid for the UE in response to a CRC check (e.g., scrambling bits of the CRC parity bit of the DCI that match the RNTI value). The UE can process the information contained in the DCI (e.g., scheduling assignment, uplink grant, power control, timeslot format indication, downlink preemption, etc.).

[0189] The UE can transmit uplink control signaling (e.g., uplink control information (UCI)) to the base station. Uplink control signaling transmission may include a Hybrid Automatic Repeat Request (HARQ) acknowledgment for a received DL-SCH transport block. The UE may transmit the HARQ acknowledgment after receiving the DL-SCH transport block. Uplink control signaling may include channel state information (CSI) indicating the channel quality of the physical downlink channel. The UE may transmit the CSI to the base station. Based on the received CSI, the base station can determine transmission format parameters (e.g., including multiple antennas and beamforming schemes) for downlink transmission. Uplink control signaling may include a scheduling request (SR). The UE may transmit an SR indicating that uplink data is available for transmission to the base station. The UE can transmit UCI (e.g., HARQ acknowledgment, CSI report, SR, etc.) via the Physical Uplink Control Channel (PUCCH) or the Physical Uplink Shared Channel (PUSCH). The UE can transmit uplink control signaling via PUCCH using one of several PUCCH formats.

[0190] Five PUCCH formats can exist, and the UE can determine the PUCCH format based on the size of the UCI (e.g., the number of uplink symbols transmitted in the UCI and the number of UCI bits). PUCCH format 0 can have a length of one or two OFDM symbols and can include two or fewer bits. If more than one or two symbols are transmitted and the number of HARQ-ACK information bits (HARQ-ACK / SR bits) with positive or negative SR is one or two, the UE can use PUCCH format 0 to transmit the UCI in the PUCCH resource. PUCCH format 1 can occupy between four and fourteen OFDM symbols and can include two or fewer bits. If four or more symbols are transmitted and the number of HARQ-ACK / SR bits is one or two, the UE can use PUCCH format 1. PUCCH format 2 can occupy one or two OFDM symbols and can include more than two bits. If more than one or two symbols are transmitted and the number of UCI bits is two or more, the UE can use PUCCH format 2. PUCCH format 3 can occupy between four and fourteen OFDM symbols and can include more than two bits. If four or more symbols are transmitted, the number of UCI bits is two or more, and the PUCCH resource does not include an orthogonal overlay code, the UE can use PUCCH format 3. PUCCH format 4 can occupy between four and fourteen OFDM symbols and can include more than two bits. If four or more symbols are transmitted, the number of UCI bits is two or more, and the PUCCH resource includes an orthogonal overlay code, the UE can use PUCCH format 4.

[0191] The base station can transmit configuration parameters of multiple PUCCH resource sets to the UE using, for example, an RRC message. These multiple PUCCH resource sets (e.g., up to four sets) can be configured on the cell's uplink BWP. A PUCCH resource set can be configured with: a PUCCH resource set index; multiple PUCCH resources (e.g., pucch-Resourceid) having PUCCH resources identified by a PUCCH resource identifier; and / or multiple (e.g., a maximum number) UCI ​​information bits that the UE can transmit using one of the multiple PUCCH resources in the PUCCH resource set. When multiple PUCCH resource sets are configured, the UE can select one PUCCH resource set from the multiple PUCCH resource sets based on the total bit length of the UCI information bits (e.g., HARQ-ACK, SR, and / or CSI). If the total bit length of the UCI information bits is two or less, the UE can select a first PUCCH resource set with a PUCCH resource set index equal to "0". If the total length of the UCI information bits is greater than two and less than or equal to the first configured value, the UE can select a second PUCCH resource set with a PUCCH resource set index equal to "1". If the total length of the UCI information bits is greater than the first configured value and less than or equal to the second configured value, the UE can select a third PUCCH resource set with a PUCCH resource set index equal to "2". If the total length of the UCI information bits is greater than the second configured value and less than or equal to the third value (e.g., 1406), the UE can select a fourth PUCCH resource set with a PUCCH resource set index equal to "3".

[0192] After determining a PUCCH resource set from multiple PUCCH resource sets, the UE can determine the PUCCH resources used for UCI (HARQ-ACK, CSI, and / or SR) transmission from the PUCCH resource set. The UE can determine the PUCCH resources based on the PUCCH resource indicator in the DCI received on the PDCCH (e.g., a DCI with DCI format 1_0 or a DCI for 1_1). The three-bit PUCCH resource indicator in the DCI can indicate one of the eight PUCCH resources in the PUCCH resource set. Based on the PUCCH resource indicator, the UE can use the PUCCH resource indicated by the PUCCH resource indicator in the DCI to transmit UCI (HARQ-ACK, CSI, and / or SR).

[0193] Figure 15 illustrates an example of a wireless device 1502 communicating with a base station 1504 according to an embodiment of the present disclosure. The wireless device 1502 and the base station 1504 may be part of a mobile communication network, such as mobile communication network 100 shown in Figure 1A, mobile communication network 150 shown in Figure 1B, or any other communication network. Figure 15 shows only one wireless device 1502 and one base station 1504; however, it should be understood that a mobile communication network may include more than one UE and / or more than one base station having the same or similar configuration as those shown in Figure 15.

[0194] Base station 1504 can connect wireless device 1502 to the core network (not shown) via radio communication through air interface (or radio interface) 1506. The communication direction from base station 1504 to wireless device 1502 via air interface 1506 is referred to as the downlink, while the communication direction from wireless device 1502 to base station 1504 via air interface 1506 is referred to as the uplink. Downlink transmissions can be separated from uplink transmissions using some combination of FDD, TDD, and / or two duplex technologies.

[0195] In the downlink, data to be transmitted from base station 1504 to wireless device 1502 can be provided to processing system 1508 of base station 1504. The data can be provided to processing system 1508 via, for example, a core network. In the uplink, data to be transmitted from wireless device 1502 to base station 1504 can be provided to processing system 1518 of wireless device 1502. Processing systems 1508 and 1518 can implement Layer 3 and Layer 2 OSI functions to process the data for transmission. Layer 2 may include, for example, the SDAP layer, PDCP layer, RLC layer, and MAC layer as shown in Figures 2A, 2B, 3, and 4A. Layer 3 may include, as shown in Figure 2B, the RRC layer.

[0196] After being processed by processing system 1508, the data to be transmitted to wireless device 1502 can be provided to transmission processing system 1510 of base station 1504. Similarly, after being processed by processing system 1518, the data to be transmitted to base station 1504 can be provided to transmission processing system 1520 of wireless device 1502. Transmission processing systems 1510 and 1520 can implement Layer 1 OSI functions. Layer 1 may include the PHY layer of Figures 2A, 2B, 3, and 4A. For transmission processing, the PHY layer may perform, for example, forward error correction coding of the transport channel, interleaving, rate matching, mapping of the transport channel to the physical channel, modulation of the physical channel, multiple-input multiple-output (MIMO) or multiple-antenna processing, etc.

[0197] At base station 1504, receiving processing system 1512 can receive uplink transmissions from wireless device 1502. At wireless device 1502, receiving processing system 1522 can receive downlink transmissions from base station 1504. Receiving processing systems 1512 and 1522 can implement Layer 1 OSI functions. Layer 1 may include the PHY layer as shown in Figures 2A, 2B, 3, and 4A. For receiving processing, the PHY layer may perform functions such as error detection, forward error correction decoding, deinterleaving, demapping of transport channel to physical channel, demodulation of physical channel, MIMO or multi-antenna processing, etc.

[0198] As shown in Figure 15, wireless device 1502 and base station 1504 may include multiple antennas. These multiple antennas can be used to perform one or more MIMO or multi-antenna techniques, such as spatial multiplexing (e.g., single-user MIMO or multi-user MIMO), transmit / receive diversity, and / or beamforming. In other examples, wireless device 1502 and / or base station 1504 may have a single antenna.

[0199] Processing systems 1508 and 1518 may be associated with memory 1514 and memory 1524, respectively. Memory 1514 and memory 1524 (e.g., one or more non-transitory computer-readable media) may store computer program instructions or code that can be executed by processing systems 1508 and / or 1518 to perform one or more of the functions discussed in this application. Although not shown in FIG. 15, transmission processing systems 1510, 1520, 1512, and / or 1522 may be coupled to memory (e.g., one or more non-transitory computer-readable media) storing computer program instructions or code that can be executed to perform one or more of their respective functions.

[0200] Processing system 1508 and / or processing system 1518 may include one or more controllers and / or one or more processors. The one or more controllers and / or one or more processors may include, for example, a general-purpose processor, a digital signal processor (DSP), a microcontroller, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) and / or other programmable logic devices, discrete gate and / or transistor logic, discrete hardware components, onboard units, or any combination thereof. Processing system 1508 and / or processing system 1518 may perform at least one of the following: signal encoding / processing, data processing, power control, input / output processing, and / or any other function that enables wireless device 1502 and base station 1504 to operate in a wireless environment.

[0201] Processing system 1508 and / or processing system 1518 may be connected to one or more peripheral devices 1516 and one or more peripheral devices 1526, respectively. The one or more peripheral devices 1516 and 1526 may include software and / or hardware providing features and / or functions, such as speakers, microphones, keyboards, displays, touchpads, power supplies, satellite transceivers, Universal Serial Bus (USB) ports, hands-free headsets, FM radio units, media players, internet browsers, electronic control units (e.g., for motor vehicles), and / or one or more sensors (e.g., accelerometers, gyroscopes, temperature sensors, radar sensors, lidar sensors, ultrasonic sensors, light sensors, cameras, etc.). Processing system 1508 and / or processing system 1518 may receive user input data from the one or more peripheral devices 1516 and / or 1526 and / or provide user output data to the aforementioned one or more peripheral devices. Processing system 1518 in wireless device 1502 may receive power from a power source and / or may be configured to distribute power to other components in wireless device 1502. The power source may include one or more power sources, such as a battery, a solar cell unit, a fuel cell unit, or any combination thereof. Processing system 1508 and / or processing system 1518 may be connected to GPS chipset 1517 and GPS chipset 1527, respectively. GPS chipset 1517 and GPS chipset 1527 may be configured to provide geographic location information for wireless device 1502 and base station 1504, respectively.

[0202] Figure 16A illustrates an example architecture for uplink transmission. The baseband signal representing the physical uplink shared channel can perform one or more functions. These functions may include at least one of the following: scrambling; modulating scrambling bits to generate complex-valued symbols; mapping complex-valued modulation symbols onto one or more transport layers; transform precoding to generate complex-valued symbols; precoding the complex-valued symbols; mapping the precoded complex-valued symbols to resource elements; generating complex-valued time-domain single-carrier frequency division multiple access (SC-FDMA) or CP-OFDM signals for antenna ports, etc. In one example, when transform precoding is enabled, an SC-FDMA signal for uplink transmission can be generated. In the example, when transform precoding is not enabled, a CP-OFDM signal for uplink transmission can be generated using Figure 16A. These functions are shown as examples, and other mechanisms are expected to be implemented in various embodiments.

[0203] Figure 16B illustrates an example structure for modulation and upsampling conversion of a baseband signal to a carrier frequency. The baseband signal can be a complex-value SC-FDMA or CP-OFDM baseband signal from the antenna port and / or a complex-value Physical Random Access Channel (PRACH) baseband signal. Filtering can be applied before transmission.

[0204] Figure 16C illustrates an example structure for downlink transmission. The baseband signal representing the physical downlink channel can perform one or more functions. These functions may include: scrambling coded bits in a codeword to be transmitted over the physical channel; modulating the scrambled bits to generate complex-valued modulation symbols; mapping the complex-valued modulation symbols onto one or more transport layers; precoding the complex-valued modulation symbols for transmission at the antenna port; mapping the complex-valued modulation symbols for the antenna port to resource elements; generating a complex-valued time-domain OFDM signal for the antenna port, etc. These functions are shown as examples, and other mechanisms are expected to be implemented in various embodiments.

[0205] Figure 16D shows another example structure for modulation and upconversion of a baseband signal to a carrier frequency. The baseband signal can be a complex-value OFDM baseband signal at the antenna port. Filtering can be applied before transmission.

[0206] A wireless device can receive one or more messages (e.g., RRC messages) from a base station, including configuration parameters for multiple cells (e.g., primary cell, secondary cell). The wireless device can communicate with at least one base station (e.g., two or more base stations in dual connectivity) via the multiple cells. The one or more messages (e.g., as part of the configuration parameters) can include parameters for configuring the wireless device at the physical layer, MAC layer, RLC layer, PCDP layer, SDAP layer, and RRC layer. For example, the configuration parameters may include parameters for configuring physical layer and MAC layer channels, bearers, etc. For example, the configuration parameters may include parameters indicating the values ​​of timers for the physical layer, MAC layer, RLC layer, PCDP layer, SDAP layer, RRC layer, and / or communication channels.

[0207] A timer can begin running once started and continues running until it stops or expires. If the timer is not running, it can be started, or if it is running, it can be restarted. The timer can be associated with a value (e.g., a timer can start or restart from a certain value, or it can start from zero and expire once it reaches that value). The duration of the timer may not be updated until the timer stops or expires (e.g., due to BWP switching). The timer can be used to measure time periods / windows of a process. When the specification refers to embodiments and procedures relating to one or more timers, it should be understood that there are multiple ways to implement the one or more timers. For example, it should be understood that one or more of the multiple ways of implementing a timer can be used to measure time periods / windows of a process. For example, a random access response window timer can be used to measure a time window for receiving a random access response. In the example, instead of starting and expiring the random access response window timer, the time difference between two timestamps can be used. When the timer restarts, the measurement process for the time window can be restarted. Other example embodiments for restarting the measurement of a time window can be provided.

[0208] Layer-1 / 2 triggered mobility (LTM) can be referred to as lower-layer triggered mobility. LTM is a procedure by which a base station (e.g., gNB, cell, network, CU, DU, source DU, candidate / target DU, etc.) can receive one or more Layer 1 / 2 (L-1 / 2) measurement reports from a radio device, such as the physical layer, media access control (MAC) layer, lower layers, etc. Based on (or based on) one or more L-1 / 2 measurement reports (which can be referred to as one or more (L-1 / 2) measurements), the base station can change / switch the serving cell of the radio device by / via / using control commands (e.g., Media Access Control (MAC) Control Element (CE), L-1 / 2 Control Command, DCI, PDCCH, Cell Handover MAC CE, LTM Command MAC CE, LTM Cell Handover Command MAC CE, etc.). The base station can prepare (e.g., indicate to the radio device) one or more candidate / target cells, for example, for LTM.

[0209] The one or more candidate / target cells may be referred to as one or more LTM candidate / target cells. One or more candidate / target cells may include one or more serving cells. One or more candidate / target cells may include one or more (candidate / target) non-serving cells. One or more candidate / target cells may include one or more (candidate / target) SCells. One or more candidate / target cells may include one or more (candidate / target) active SCells. One or more candidate / target cells may include one or more (candidate / target) deactivated SCells.

[0210] A base station may provide a radio device with one or more candidate / target (LTM) cell configurations for LTM (or LTM procedures / processes) via one or more messages (e.g., RRC messages). The one or more messages may include configuration parameters (e.g., RRC configuration parameters). The one or more messages may indicate one or more candidate / target cells. The one or more candidate / target (LTM) cell configurations may be used for the one or more candidate / target cells / indicate the one or more candidate / target cells / are associated with the one or more candidate / target cells / are associated with the one or more candidate / target cells. Each candidate / target (LTM) cell configuration may be used for a corresponding candidate / target cell among the one or more candidate / target cells / indicate the corresponding candidate / target cell among the one or more candidate / target cells / are associated with a corresponding candidate / target cell among the one or more candidate / target cells. Then (e.g., after the radio device receives the one or more messages), an LTM cell handover may be triggered (e.g., by the base station / gNB) by the base station selecting one of the one or more candidate / target (LTM) cell configurations as the target (LTM) cell configuration for LTM. One or more candidate / target (LTM cell) configurations can be added by the network / base station via RRC signaling. One or more candidate / target (LTM cell) configurations can be modified by the network / base station via RRC signaling. One or more candidate / target (LTM cell) configurations can be released by the network / base station via RRC signaling.

[0211] In the example, one or more candidate / target (LTM cell) configurations can be one or more RRCReconfigurations (messages). Each RRCReconfiguration in the one or more RRCReconfigurations can be used for a corresponding candidate / target cell in one or more candidate / target cells / associated with a corresponding candidate / target cell in one or more candidate / target cells. In the example, one or more candidate / target (LTM cell) configurations can be one or more CellGroupConfig information elements (IEs). Each CellGroupConfigIE in the one or more CellGroupConfigIEs can be used for a corresponding candidate / target cell in one or more candidate / target cells / associated with a corresponding candidate / target cell in one or more candidate / target cells.

[0212] In LTM, the one or more candidate / target (LTM cell) configurations can be provided as one or more differential configurations on top of one or more reference configurations (e.g., transmitted by the base station to the radio device via one or more second messages). The one or more reference configurations can be managed individually by the base station, for example. The radio device can store each of the one or more reference configurations as a separate configuration.

[0213] In LTM, the user plane can continue without a reset whenever possible (e.g., intra-DU LTM, intra-DU mobility, intra-DU handover, etc.), with the goal of avoiding additional delays in data loss and data recovery. Security updates are not required in LTM. Subsequent LTMs between one or more candidate / target cells can be performed by the radio device / base station without RRC reconfiguration. For example, after triggering / completing LTM, the radio device may not release the candidate / target (LTM cell) configuration in the one or more candidate / target (LTM cell) configurations.

[0214] LTM can support / include intra-DU mobility (e.g., intra-DU mobility). LTM can support / include intra-CU mobility (e.g., intra-CU mobility). LTM can support / include inter-DU mobility (e.g., inter-DU mobility). LTM can support / include inter-CU mobility (e.g., inter-CU mobility). LTM can support / include inter-frequency mobility, including mobility to inter-frequency cells that are not the current serving cell.

[0215] LTM can support / include PCell changes in non-carrier aggregation (CA) scenarios. For example, the source / serving cell can be a PCell. The candidate / target cell may not be a PCell. Radio devices can perform cell handover (e.g., cell handover via LTM, cell handover command MAC CE, LTM command MAC CE, etc.) to the candidate / target cell. After the cell handover, the candidate / target cell can be a PCell. After the cell handover, the source / serving cell may not be a PCell.

[0216] LTM can support / include PCell changes in CA scenarios that do not have SCell changes.

[0217] LTM can support / include PCell changes with SCell changes in CA scenarios. For example, the target candidate / target cell (e.g., target PCell / target SCell) may not be the current serving cell (CA to CA scenario with PCell changes). For example, the target PCell may be the current SCell. For example, the target SCell may be the current PCell.

[0218] The source / serving cell can be a PCell, SCell, PSCell, SpCell, and / or similar. Each of the one or more candidate / target cells can be a PCell, SCell, active SCell, deactivated SCell, PSCell, SpCell, non-serving cell, unlicensed cell, cell operating using shared spectrum channel access, FR1 cell, FR2 cell, and / or similar.

[0219] LTM can support / include dual connectivity (DC) scenarios, at least for PSCell changes without the participation of a master node (MN), such as within a secondary node (SN).

[0220] Cell handover triggering information for LTM can be transmitted in control commands (e.g., by / from the base station to the radio device) such as MAC CE, activation command, cell handover command, cell handover MAC CE, cell handover command MAC CE, LTM command MAC CE, DCI, PDCCH command, etc. The LTM (cell handover) command MAC CE may include at least a candidate / target (LTM cell) configuration index. The candidate / target (LTM cell) configuration index may indicate / identify a candidate / target cell (and / or candidate / target (LTM cell) configuration from one or more candidate / target cells (and / or one or more candidate / target (LTM cell) configurations) / among the one or more candidate / target cells / among the one or more candidate / target cells. Cell-specific radio bearer and / or measurement configurations may be one of the one or more candidate / target (LTM cell) configurations / part of each candidate / target (LTM cell) configuration.

[0221] The LTM (cell handover) command MAC CE can indicate the TCI state to be activated for the target / candidate cell (or other beam information, such as reference signal, QCL assumption, spatial filter, spatial domain filter, spatial domain transmission filter, spatial domain reception filter, transmission beam, reception beam, etc.).

[0222] SCell activation / deactivation (in SCells associated with one or more candidate / target (cell) configurations) can be performed simultaneously with LTM (cell handover) command MAC CE (e.g., which may be referred to as LTM trigger MAC CE, cell handover MAC CE, cell handover command, cell handover command / indication, LTM command MAC CE, control command, etc.) (e.g., by a radio device and / or base station).

[0223] The radio device can perform contention-based random access (CBRA) or contention-free random access (CFRA) during / after cell handover (e.g., after receiving a control command, such as a cell handover MACCE). If the radio device does not need to acquire the target / candidate cell's TA during / after cell handover (e.g., in response to the radio device determining the target / candidate cell's TA before / after receiving a control command), the radio device can skip the random access (RA) procedure (e.g., CBRA and / or CFRA). The RACH resources used for CFRA can be provided by the base station in one or more configuration parameters (or configured via one or more candidate / target (LTM cells)).

[0224] In the example, the LTM (cell handover) command MAC CE can instruct / provide CFRA resources. The radio device can use CFRA resources to perform CFRA in / via the candidate / target cell.

[0225] Figure 17 illustrates the procedure for LTM. Subsequent LTMs can be completed / executed (e.g., by the base station and / or radio device) by repeating early synchronization (as shown in Figure 17), LTM execution, and / or LTM completion steps / procedures (as shown in Figure 17) without releasing other candidates (e.g., the one or more candidate / target (LTM cell) configurations) after each LTM completion.

[0226] In the example of Figure 17, a radio device (e.g., the UE in Figure 17) may transmit one or more measurement reports (e.g., the measurement reports in Figure 17). The one or more measurement reports may, for example, be one or more Layer 3 (L3) measurement reports. The radio device may transmit the one or more (L3) measurement reports to / via a base station / gNB (e.g., via cell 0, the source / serving cell in Figure 17). The base station may, for example, determine whether to use / perform LTM based on the one or more (L3) measurement reports. The base station may, for example, initiate LTM candidate preparation (e.g., LTM preparation as shown in Figure 17) by coordinating with one or more candidate / target cells (e.g., one or more DUs, one or more source / serving DUs, one or more candidate / target DUs, etc.).

[0227] The base station may transmit one or more messages (e.g., RRC messages) to the radio device. The one or more messages may include, for example, one or more candidate / target (LTM) cell configurations for LTM / LTM procedures. The one or more messages may include one or more configuration parameters indicating / including one or more candidate / target (LTM) cell configurations. The one or more candidate / target (LTM) cell configurations may be one or more RRCReconfigurations (parameters / messages). The radio device may receive, for each of the one or more candidate / target cells, a corresponding candidate / target (LTM) cell configuration from / via the base station (e.g., via the source / serving cell). The radio device may store one or more candidate / target (LTM) cell configurations of the one or more candidate / target cells. The radio device may, for example, transmit an RRCReconfigurationComplete message to the base station (e.g., via the source / serving cell, cell 0 in Figure 17) based on receiving and / or storing the one or more candidate / target (LTM) cell configurations.

[0228] The wireless device can perform early synchronization (e.g., early synchronization as shown in Figure 17). Early synchronization can include DL synchronization to / with / for / for the candidate / target cell in the one or more candidate / target cells (e.g., indicated in the one or more candidate / target (LTM cell) configuration). The wireless device can, for example, perform DL synchronization to / with / for / for the candidate / target cell in the one or more candidate / target cells before receiving an LTM (cell handover) command MAC CE (e.g., cell handover MAC CE, LTM command MAC CE).

[0229] The radio device can perform a timing advance (TA) acquisition (e.g., using the RA procedure shown in Figure 17, by transmitting an RA preamble, or in the absence of an RA procedure, e.g., based on TA measurements based on the radio device / UE). Early synchronization (e.g., early synchronization as shown in Figure 17) may include TA acquisition (e.g., which may be referred to as early TA acquisition (ETA)). TA acquisition may be referred to as, for example, uplink (UL) synchronization. The radio device can perform TA acquisition (e.g., acquiring the TA for a candidate / target cell / the candidate / target cell / associated with the candidate / target cell in one or more candidate target cells). The radio device can perform TA acquisition, for example, before receiving an LTM (cell handover) command MAC CE (e.g., LTM command MAC CE, cell handover MAC CE).

[0230] The wireless device can acquire a TA using an RA procedure (e.g., as shown in Figure 17) based on receiving control commands (e.g., DCI, PDCCH commands) directed to / for / to / via the candidate / target cell among the one or more candidate / target cells (triggering RA channel (RACH) transmission, such as RA preamble transmission, RACH transmission, physical RACH (PRACH) transmission, RA preamble / PRACH transmission, etc.). The wireless device can receive control commands (e.g., DCI, PDCCH commands) from / via the source / serving cell.

[0231] The wireless device can perform L-1 / 2 measurements (e.g., measurements of one or more RSs) on each / any of the one or more candidate / target cells. The wireless device can transmit L-1 / 2 (e.g., lower layer, physical layer, MAC layer, etc.) measurement reports to the base station (e.g., via the source / serving cell). The wireless device can determine the L-1 / 2 measurement report based on measurements from / associated with / associated with the one or more candidate / target cells, wherein at least one of the one or more RSs originates from / associated with a corresponding candidate / target cell in the one or more candidate / target cells.

[0232] The base station / gNB can, for example, determine / determine to perform an LTM cell handover to a target / candidate cell among the one or more candidate / target cells based on (received) L-1 / 2 measurements. The base station can (e.g., via the source / serving cell) transmit control commands (e.g., cell handover, cell handover for LTM, etc.) that trigger the LTM cell handover (e.g., cell handover, cell handover for LTM, etc.). The control commands may include a candidate / target (LTM cell) configuration index. The candidate / target (LTM cell) configuration index may indicate / identify the target / candidate cell / candidate / target / candidate cell configuration associated with the target / candidate cell in one or more candidate / target (LTM cell) configurations. The candidate / target (LTM cell) configuration index may indicate / identify a candidate / target cell among the one or more candidate / target cells. The radio device can switch to / use the (LTM) candidate / target cell configuration indicated in the control commands.

[0233] The wireless device can perform the RA procedure via the candidate / target cell / in the candidate / target cell (e.g., if the TA for the candidate / target cell / candidate / target cell is unavailable / invalid at the wireless device).

[0234] For example, a radio device may indicate, via a candidate / target cell / gNB / base station, the successful completion of a Level 1 (LTM) cell handover to a candidate / target cell. The radio device may transmit one or more uplink (UL) messages to indicate LTM completion. LTM completion may include the successful completion of a Level 1 (LTM) cell handover to a candidate / target cell.

[0235] Although this disclosure may refer to LTM (or LTM procedure), such procedure may alternatively be referred to as a cell handover procedure triggered by control commands / cell handover commands (e.g., MAC CE, Layer 1 / 2 commands / messages, etc.), or as Layer 1 / 2 triggered mobility, MAC CE triggered cell handover procedure, non-handover, non-handover mobility, non-handover reconfiguration with synchronization, non-reconfiguration with synchronization mobility, etc.

[0236] Early synchronization (e.g., early synchronization as shown in Figure 17) may include early TA acquisition (ETA). For ETA, the radio device may execute an RA procedure. The RA procedure may be referred to as, for example, an ETA procedure / process or an ETA RA procedure. The RA procedure may be referred to as, for example, an LTM TA acquisition. The RA procedure (e.g., for ETA, LTM TA acquisition, etc.) may be triggered / initiated by, for example, a base station. The RA procedure (e.g., for ETA, LTM TA acquisition, etc.) may be triggered / initiated, for example, by / via (Layer 1) control commands (e.g., downlink control information (DCI), DCI format 1_0, physical downlink control channel (PDCCH) commands, etc.). In the radio device (e.g., the MAC entity of the radio device), at any given time, there may be (only) one RA procedure (e.g., an RA procedure) in progress.

[0237] A wireless device can transmit / perform RA preamble / PRACH transmissions for RA procedures. As an example, transmitting / performing RA preamble / PRACH transmissions can be referred to as a PRACH transmission. A wireless device can transmit / perform RA preamble / PRACH transmissions via one or more PRACH / RA resources, on one or more PRACH / RA resources, or using one or more PRACH / RA resources.

[0238] Based on the transmission / execution of the RA preamble / PRACH transmission (e.g., after the transmission / execution of the RA preamble / PRACH transmission, in response to the transmission / execution of the RA preamble / PRACH transmission, or once the transmission / execution of the RA preamble / PRACH transmission is performed), the wireless device can monitor the PDCCH for the RA response identified by the RA-RNTI associated with the RA preamble / PRACH transmission while the ra-ResponseWindow (e.g., RAR window, RAR timer, etc.) is running.

[0239] In the example, one or more messages (e.g., RRC message, MAC CE, DCI, PDCCH command, etc.) can indicate to the radio device whether the RACH for the PDCCH command for the candidate / target cell in LTM requires RAR.

[0240] For example, the one or more candidate / target (LTM cell) configurations (e.g., one / each candidate / target (LTM cell) configuration in the one or more candidate / target (LTM cell) configurations) may indicate whether RAR is required (e.g., RAR monitoring, RAR configuration, etc.) for a RA procedure initiated / triggered by (Layer 1) control commands of the one or more candidate / target cells towards the candidate / target cell / to the candidate / target cell / for the candidate / target cell / via the candidate / target cell). For example, one / each candidate / target (LTM cell) configuration in the one or more candidate / target (LTM cell) configurations may include a field indicating whether RAR is required (e.g., noRAR included in / within / in the LTM-EarlySyncConfig information element, which may be included in the candidate / target (LTM cell) configurations in the one or more candidate / target (LTM cell) configurations).

[0241] For example, a first candidate / target (LTM cell) configuration in one or more candidate / target cell configurations may be associated with a first candidate / target cell in one or more candidate / target cells. Similarly, a second candidate / target (LTM cell) configuration in one or more candidate / target cell configurations may be associated with a second candidate / target cell in one or more candidate / target cells.

[0242] In the example, the first candidate / target (LTM cell) configuration can indicate that RAR is required for the first candidate / target cell (e.g., the associated RA procedure) among the one or more candidate / target cells (e.g., RAR monitoring is required / required, radio device anticipates RAR, configures RAR monitoring, configures RAR, etc.) (e.g., noRAR can be set to false). In response to the transmission of an RA preamble for an RA procedure triggered / initiated by a (Layer 1) control command from LTM (e.g., for / via the first candidate / target cell), the radio device can monitor the PDCCH (e.g., when the ra-ResponseWindow (e.g., RAR window, RAR timer, etc.) is running) identified by the RA-RNTI associated with (or corresponding to) the RA preamble / PRACH transmission.

[0243] In the example, the wireless device may not receive the RAR identified by the RA-RNTI associated with (or corresponding to) the RA preamble (e.g., while the ra-ResponseWindow (e.g., the RAR window, RAR timer, etc.) is running). For example, the wireless device may increment a counter (e.g., a preamble transmission counter) based on the absence of a RAR identified by the RA-RNTI associated with (or corresponding to) the RA preamble (e.g., while the ra-ResponseWindow (e.g., the RAR window, RAR timer, etc.)).

[0244] In the example, the ra-ResponseWindow (e.g., a RAR window, a RAR timer, etc.) may expire. The wireless device may not receive a RAR containing / corresponding to an RA preamble (or RA preamble identifier). For example, the wireless device may increment a counter based on the expiration of the ra-ResponseWindow (e.g., a RAR window, a RAR timer, etc.) and / or the failure to receive a RAR containing / corresponding to an RA preamble (or RA preamble identifier).

[0245] In another example, the second candidate / target (LTM cell) configuration may indicate that RAR is not required for the second candidate / target cell (e.g., the associated RA procedure) among the one or more candidate / target cells (e.g., RAR monitoring is not required / required, the radio device does not expect RAR, RAR monitoring is not configured, RAR is not configured, etc.) (e.g., noRAR can be set to true). In response to transmitting an RA preamble for an RA procedure triggered / initiated by a (Layer 1) control command from LTM (e.g., for / via the first candidate / target cell), the radio device may not monitor / receive the PDCCH (e.g., when the ra-ResponseWindow (e.g., RAR window, RAR timer, etc.) is running) identified by the RA-RNTI associated with (or corresponding to) the RA preamble.

[0246] In the prior art, a wireless device can increment a preamble transmission counter after transmitting the RA preamble (e.g., without waiting / monitoring / receiving the RAR or RAR window). Incrementing the preamble transmission counter after transmitting the RA preamble can be adapted to provide a method for incrementing the preamble transmission counter when the RAR is not needed / configured for the RA procedure (e.g., as described above for a second candidate / target cell).

[0247] For example, the wireless device can increment a preamble transmission counter after transmitting the RA preamble. The value of the preamble transmission counter (e.g., based on increment / after increment) can reach a configured maximum value (e.g., preambleTransMax).

[0248] In existing implementations, based on the value of the preamble transmission counter (e.g., based on incrementing / after incrementing) reaching a configured maximum value, the wireless device can determine / declare (e.g., indicate to the base station via one or more uplink (UL) messages) RA failure / LTM TA acquisition / ETA failure. However, the RA preamble can be successfully received / decoded by the base station. For example, even though the base station successfully receives / decodes the RA preamble, the wireless device may unnecessarily determine / declare RA / LTM TA acquisition / ETA failure. Unnecessarily determining / declare RA / LTM TA acquisition / ETA failure can lead to increased latency, increased signaling overhead, increased jitter / delay during / in the LTM procedure, increased power consumption, and / or reduced battery life of the wireless device.

[0249] Given the existing technology, when the RA procedure / process associated with the TA acquisition / ETA of the candidate / target cell is not configured with RAR (e.g., indicating that the RA procedure does not require RAR), it is necessary to improve the procedure for incrementing counters (e.g., preamble transmission counters) during / for the LTM / ETA procedure.

[0250] Embodiments of this disclosure relate to methods for incrementing counters (e.g., preamble transmission counters, preamble power ramp counters, LTM counters, ETA counters, RACH counters, etc.). These and other features of this disclosure are further described below.

[0251] In an example embodiment, the wireless device may receive one or more configuration parameters indicating that RAR monitoring is not required / needed / configured (e.g., the one or more configuration parameters may include a noRAR field set to true). The wireless device may receive control commands (e.g., DCI, PDCCH commands) indicating an initial transmission of RA preamble / PRACH. The wireless device may transmit / perform RA preamble / PRACH transmission based on the received control commands (e.g., DCI, PDCCH commands). The wireless device may increment a counter (e.g., a preamble transmission counter, a preamble power ramp counter, etc.) without responding to the transmission / performance of RA preamble / PRACH. The wireless device may receive a second control command (e.g., DCI, PDCCH command) indicating a retransmission of a second RA preamble / PRACH. In response to receiving the second control command (e.g., DCI, PDCCH command) indicating a retransmission of a second RA preamble / PRACH, the wireless device may (determine) increment a counter (e.g., a preamble transmission counter, a preamble power ramp counter, etc.). For example, a wireless device can transmit / retransmit a second RA preamble / PRACH transmission after incrementing a counter (e.g., a preamble transmission counter, a preamble power ramp counter, etc.). For instance, if / based on a counter (e.g., a preamble transmission counter, a preamble power ramp counter, etc.) less than a (maximum configured) value (e.g., preambleTransMax), the wireless device can transmit / retransmit a second RA preamble / PRACH transmission after incrementing the counter (e.g., a preamble transmission counter, a preamble power ramp counter, etc.).

[0252] The exemplary embodiments of this disclosure can provide enhancements for incrementing, maintaining, and / or resetting counters (e.g., preamble transmission counters, preamble power ramp counters, etc.). By implementing the exemplary embodiments of this disclosure, wireless devices can reduce unnecessary declarations / indications of radio link failures (RLF), RA failures, LTM TA acquisition / ETA failures, etc., to the base station. Reducing unnecessary declarations / indications of radio link failures (RLF), RA failures, LTM TA acquisition failures, etc., can lead to increased battery life, reduced signaling overhead, reduced power consumption, and / or reduced latency for the wireless device.

[0253] Figure 18 shows an example timing diagram of an RA procedure according to an embodiment of the present disclosure.

[0254] In an example embodiment, the wireless device receives one or more messages. The wireless device may receive the one or more messages from a base station. The base station may transmit one or more messages. The base station may be, for example, a source / serving base station (e.g., a base station serving a source / serving cell (e.g., cell 0 in Figure 18)). The one or more messages may be Radio Resource Control (RRC) messages (e.g., one or more RRC setup messages, one or more RRC reconfiguration messages, one or more RRC connection re-establishment messages, one or more RRC release messages, etc.). The one or more messages may be system information messages (e.g., one or more broadcast messages, one or more System Information Blocks (SIBs), etc.). In the example, the wireless device may receive one or more messages from a relay node. In the example, the wireless device may receive the one or more messages from another wireless device (e.g., a Transmit and / or Receive Point (TRP), a vehicle, a remote radio head, etc.).

[0255] The message may include one or more configuration parameters (e.g., the configuration parameters in Figure 18). The one or more configuration parameters may be used for a group / multiple cells.

[0256] The group / multiple cells may include cells. For example, the group of cells may simply be a single cell, or it may be multiple cells.

[0257] A cell can be, for example, a serving / source cell (e.g., cell 0 in Figure 18). In the example, at least one of one or more configuration parameters can be cell-specific. In the example, a cell can be a primary cell (Pcell). In the example, a cell can be a primary-secondary cell (PSCell). In the example, a cell can be a secondary cell (SCell). The cell can be a secondary cell configured with a PUCCH (e.g., PUCCH SCell). In the example, a cell can be a special cell (SpCell). For dual connectivity (DC) operation, SpCell can refer to (or indicate) the PCell of the MCG or the PSCell of the SCG; otherwise, SpCell can refer to (or indicate) the PCell.

[0258] In the example, the cell can be an unlicensed (or shared spectrum channel access) cell, for example, operating in an unlicensed frequency band or operating with shared spectrum channel access. In the example, the cell can be a licensed cell, for example, operating in a licensed frequency band. In the example, the cell can operate in a first frequency range (FR1). For example, FR1 can include frequency bands below 6 GHz. In the example, the cell can operate in a second frequency range (FR2). For example, FR2 can include frequency bands from 24 GHz to 52.6 GHz. In the example, the cell can operate in a third frequency range (FR3). For example, FR3 can include frequency bands from 52.6 GHz to 71 GHz. For example, FR3 can include frequency bands starting at (or above) 52.6 GHz.

[0259] In the example, the radio device can perform uplink transmissions (e.g., PUSCH, PUCCH, PUCCH) of the cell / via the cell at a first time and at a first frequency. The radio device can perform downlink receptions (e.g., PDCCH, PDSCH) of the cell / via the cell at a second time and at a second frequency. In the example, the cell can operate in Time Division Duplex (TDD) mode. In TDD mode, the first and second frequencies can be the same. In TDD mode, the first and second times can be different. In the example, the cell can operate in Frequency Division Duplex (FDD) mode. In FDD mode, the first and second frequencies can be different (e.g., not the same). In FDD mode, the first and second times can be the same (e.g., not different).

[0260] In the example, the wireless device can be in RRC connected (RRC_CONNECTED) mode. In the example, the wireless device can be in RRC idle (RRC_IDLE) mode. In the example, the wireless device can be in RRC inactive (RRC_INACTIVE) mode.

[0261] In the example, a cell may include multiple BWPs. The multiple BWPs may include one or more uplink BWPs, which include the cell's uplink BWP (UL BWP). The multiple BWPs may also include one or more downlink BWPs, which include the cell's downlink BWP.

[0262] In the example, one of the plurality of BWPs can be in an active state or an inactive state (or a deactivated state). In the example, when one or more downlink BWPs are active, the radio device can monitor downlink channels / signals (e.g., PDCCH, DCI, CSI-RS, PDSCH) on / to / via the downlink BWP. In the example, when one or more downlink BWPs are active, the radio device can receive PDSCH on / to / for the downlink BWP. In the example, when one or more downlink BWPs are inactive, the radio device cannot monitor downlink channels / signals (e.g., PDCCH, DCI, CSI-RS, PDSCH) on / to / for the downlink BWP. When one or more downlink BWPs are inactive, the radio device can stop monitoring (or receiving) downlink channels / signals (e.g., PDCCH, DCI, CSI-RS, PDSCH) on / to / for the downlink BWP. In the example, when one or more downlink BWPs are inactive, the radio device cannot receive PDSCH on / via / for the downlink BWP. When one or more downlink BWPs are inactive, the radio device can stop receiving PDSCH on / via / for the downlink BWP.

[0263] One or more configuration parameters can indicate the subcarrier spacing (or set of parameters) used for the downlink BWP.

[0264] One or more configuration parameters can indicate the subcarrier spacing (or set of parameters) used for the uplink BWP.

[0265] The subcarrier spacing value (for the downlink BWP and / or uplink BWP) can be / indicated, for example, 15 kHz (mu=0). The subcarrier spacing value can be / indicated, for example, 30 kHz (mu=1). The subcarrier spacing value can be / indicated, for example, 60 kHz (mu=2). The subcarrier spacing value can be / indicated, for example, 120 kHz (mu=3). The subcarrier spacing value can be / indicated, for example, 240 kHz (mu=4). The subcarrier spacing value can be / indicated, for example, 480 kHz (mu=5). The subcarrier spacing value can be / indicated, for example, 960 kHz (mu=6). For example, 480 kHz may be valid / applicable in FR3. For example, 960 kHz may be valid / applicable in FR3. For example, 240 kHz may be valid / applicable in FR3. For example, 120 kHz may be valid / applicable in FR3.

[0266] In the example, the cell can be the serving cell of the wireless device. In the example, the cell can be the source / serving cell (e.g., cell 0 in Figure 17 and / or Figure 18).

[0267] In an example embodiment, the wireless device may transmit measurement reports to / from / towards / via a source / serving cell (e.g., Layer 3 or L3), as shown in Figure 17. The base station may, for example, prepare one or more candidate / target cells for LTM based on the measurement reports. In one example, the wireless device may request one or more candidate / target (LTM cell) configurations from the base station. In another example, the base station may determine to transmit the one or more candidate / target (LTM cell) configurations (e.g., without a request from the wireless device).

[0268] In the example embodiment of Figure 18, the wireless device may receive the one or more messages from a base station (e.g., a source / serving base station, a base station serving a source / serving cell (e.g., cell 0)). The wireless device may receive the one or more messages via / through / from a source / serving cell (e.g., cell 0 in Figure 18). The one or more messages may include one or more configuration parameters (e.g., RRC configuration parameters, RRC reconfiguration parameters, RACH configuration parameters, TCI status, etc.). The one or more configuration parameters may include the one or more candidate / target (LTM cell) configurations. The one or more candidate / target (LTM cell) configurations may be used for or associated with one or more LTM procedures.

[0269] The one or more candidate / target (LTM cell) configurations can be used or associated with the one or more candidate / target cells (e.g., for LTM). Each candidate / target (LTM cell) configuration in the one or more candidate / target (LTM cell) configurations can be used or associated with a corresponding candidate / target cell in the one or more candidate / target cells.

[0270] The one or more candidate / target cells may include a first candidate / target cell (e.g., cell 1 in Figure 18). The one or more candidate / target cells may include a second candidate / target cell (e.g., cell 2 in Figure 18). The one or more candidate / target (LTM cell) configurations may include a first candidate / target (LTM cell) configuration (e.g., the configuration of cell 1 in Figure 18). The one or more candidate / target (LTM cell) configurations may include a second candidate / target (LTM cell) configuration (e.g., the configuration of cell 2 in Figure 18). The first candidate / target (LTM cell) configuration may be used / associated with the first candidate / target cell. The second candidate / target (LTM cell) configuration may be used / associated with the second candidate / target cell.

[0271] In the example of Figure 18, the wireless device may receive (e.g., from the source / serving base station and / or via the source / serving cell) one or more configuration parameters during a first time interval (e.g., time, duration, time period, time slot, subframe, radio frame, system frame number, time slot, etc.). In the example of Figure 18, the first time interval is denoted as T1.

[0272] In the example, the first candidate / target (LTM cell) configuration can indicate that the first candidate / target cell does not require / needs RAR (monitoring). For example, the first candidate / target (LTM cell) configuration can include a noRAR field that can be set to true. The first candidate / target (LTM cell) configuration can indicate that the first candidate / target cell does not require / needs RAR (monitoring), for example, based on the first candidate / target (LTM cell) configuration including a noRAR field set to true.

[0273] In the example, the one or more messages may indicate that the first candidate / target cell does not require / requires RAR (monitoring). In the example, the (source / serving) base station may, for example, indicate to the radio device via the source / serving cell (e.g., cell 0 in Figure 18) that the first candidate / target cell does not require / requires RAR (monitoring). The first candidate / target (LTM cell) configuration may include a field indicating that the first candidate / target cell does not require / requires RAR. The field may be, for example, RAwithoutRAR or noRAR. In response to the field being set to a first value (e.g., '0', '1', 'true', 'false', etc.), the first candidate / target (LTM cell) configuration may indicate that the first candidate / target cell does not require / requires RAR (monitoring). In response to the field being set to a second value (e.g., '0', '1', 'true', 'false', etc.), the first candidate / target (LTM cell) configuration may indicate that the first candidate / target cell requires / requires RAR (monitoring).

[0274] The statement that the first candidate / target cell does not require / does not need RAR (monitoring) can mean / refer to / indicate / include that the radio device is not required / does not need / is not permitted to monitor RAR / PDCCH / DCI in response to (or subsequently) transmitting / performing RA preamble / PRACH transmissions for / via / to / towards the first candidate / target cell's RA procedures (e.g., for early synchronization, early TA acquisition, ETA, etc.). The radio device can transmit / perform RA preamble / PRACH transmissions for / via / towards the first candidate / target cell's RA procedures. In response to a first candidate / target (LTM cell) configuration indicating that the first candidate / target cell does not require / need RAR (monitoring), the radio device may not monitor (for) PDCCH / RAR / DCI after transmitting / performing RA preamble / PRACH transmissions.

[0275] In the example, the second candidate / target (LTM cell) configuration may indicate that the first candidate / target cell requires / needs RAR (monitoring) (e.g., based on the second candidate / target (LTM cell) configuration including a noRAR field set to false). In the example, the (source / serving) base station may, for example, indicate to the radio device via the source / serving cell (e.g., cell 0 in Figure 18) that the second candidate / target cell requires / needs RAR (monitoring). The first candidate / target (LTM cell) configuration may include a field indicating that the second candidate / target cell requires / needs RAR (monitoring) a second time. In another example, the second candidate / target (LTM cell) configuration may not include the field (e.g., noRAR or RAwithoutRAR). In response to the second candidate / target (LTM cell) configuration not including the field, the second candidate / target (LTM cell) configuration may indicate that the first candidate / target cell requires / needs RAR (monitoring). For example, an RA procedure not associated with LTM (procedure) may always require / need RAR (monitoring). An RA procedure for LTM / ETA may be referred to as a 1-step RA procedure / process.

[0276] In the example, the wireless device receives a first control command (e.g., a DCI or PDCCH command). The first control command (e.g., a DCI or PDCCH command) may include an index for a first RA preamble / PRACH transmission, an uplink or supplementary uplink indicator, an RS (e.g., an SS / PBCH block, SSB) index, and / or a PRACH mask index indicating the RA channel timing associated with the RS used for the first RA preamble / PRACH transmission.

[0277] The radio device may receive a first control command (e.g., DCI, PDCCH command) via a source / serving cell (e.g., cell 0 in Figure 18). The radio device may also receive the first control command (e.g., DCI, PDCCH command) via / from a source / serving base station (e.g., source / serving DU). The radio device receives the first control command (e.g., DCI, PDCCH command) during a second time interval (e.g., T2 in Figure 18). In the example, T2 may be after T1. In the example, T2 may partially / completely overlap with T1. In the example, T2 may be the same as T1.

[0278] In the example, a first control command (e.g., DCI, PDCCH command) can initiate / trigger a first RA procedure (e.g., used for / associated with an LTM / ETA process / procedure). The first RA procedure can be used for one or more candidate / target cells (e.g., cell 1 in Figure 18) / is the RA procedure of the candidate / target cell / associated with the candidate / target cell.

[0279] A first control command (e.g., DCI, PDCCH command) may indicate the initial transmission of a first RA preamble / PRACH. The first control command (e.g., DCI, PDCCH command) may include fields (e.g., bit fields, multi-bit fields, etc.). These fields may indicate the initial transmission of a first RA preamble / PRACH.

[0280] In the example, if (e.g., when or in response to) the one or more configuration parameters indicate that RAR (monitoring) is not required / needed and the cell indicated by the cell indicator field in the first control command (e.g., DCI, PDCCH command) is a candidate / target cell (e.g., cell 1 in Figure 18), then the field may be a 1-bit field indicating the initial transmission or retransmission of the PRACH / RA preamble. If (or when or in response to) the cell indicated by the cell indicator field in the first control command (e.g., DCI, PDCCH command) is not a candidate / target cell (e.g., a serving cell, such as cell 0 in Figure 18), then the field may be retained.

[0281] For example, the wireless device can initialize / reset (e.g., non-increment) a counter based on a first control command (e.g., DCI, PDCCH command) indicating the initial transmission of the first RA preamble / PRACH transmission. In the example, the counter could be a preamble transmission counter (PTC). The counter can be used to count the number of RA preamble / PRACH transmissions (or the number of unsuccessful RA preamble / PRACH transmissions). In the example, the counter could be a preamble power ramp counter (PPRC). The counter can be used to determine the transmit / transmit power used to transmit / perform the RA preamble / PRACH transmission. For example, the wireless device can determine the transmit / transmit power based on a first equation. The first equation could be, for example, transmit / transmit power (in dB) = min{maximum output power configured for the wireless device, path loss (in dB) + preambleReceivedTargetPower + DELTA_PREAMBLE + (counters (e.g., preamble transmission counter, preamble power ramp counter) - 1) × PREAMBLE_POWER_RAMPING_STEP + POWER_OFFSET_2STEP_RA}, wherein one or more configuration parameters and / or the first candidate / target (LTM cell) configuration can indicate preambleReceivedTargetPower, DELTA_PREAMBLE, POWER_OFFSET_2STEP_RA, and PREAMBLE_POWER_RAMPING_STEP}.

[0282] In the example, the counter may include at least two (sub)counters. The first (sub)counter of the at least two (sub)counters may be a PTC. The second (sub)counter of the at least two (sub)counters may be a PPRC.

[0283] Initializing / resetting a counter (e.g., a preamble transmission counter, a preamble power ramp counter) may include setting the value of the counter (e.g., a preamble transmission counter, a preamble power ramp counter) to a first value. For example, the first value may be one. For example, the first value may be zero. The first value may be, for example, the maximum configured / possible value (e.g., preambleTransMax) of the counter (e.g., a preamble transmission counter, a preamble power ramp counter).

[0284] Initialization / reset counters (e.g., preamble transmission counters, preamble power ramp counters) may, for example, include non-incrementing counters (e.g., preamble transmission counters, preamble power ramp counters). Initialization / reset counters (e.g., preamble transmission counters, preamble power ramp counters) may, for example, include sustain counters (e.g., preamble transmission counters, preamble power ramp counters) (e.g., maintaining / holding their value, keeping them at the same value, etc.).

[0285] After resetting / initializing counters (e.g., in response to, when, based on, etc.) such as preamble transmission counters, preamble power ramp counters, the wireless device can transmit / perform a first RA preamble / PRACH transmission. In the example of Figure 18, the wireless device can transmit / perform a first RA preamble / PRACH transmission via a first candidate / target cell at a third time interval T3. T3 may, for example, follow T2. T3 may, for example, partially / completely overlap with T2.

[0286] The first control command (e.g., DCI, PDCCH command) may, for example, indicate a first candidate / target cell among the one or more candidate / target cells. For example, the first control command (e.g., DCI, PDCCH command) may include a field indicating a first candidate / target cell (e.g., cell 1 in FIG. 18) among the one or more candidate / target cells. For example, the first control command (e.g., DCI, PDCCH command) may include a field indicating a first candidate / target (LTM cell) configuration associated with the first candidate / target cell in the one or more candidate / target (LTM cell) configurations. The radio device may, for example, transmit / perform a first RA preamble / PRACH transmission via the first candidate / target cell / on the first candidate / target cell / through the first candidate / target cell / for the first candidate / target cell / towards the first candidate / target cell based on the first control command (e.g., DCI, PDCCH command) indicating the first candidate / target cell (e.g., cell 1 in FIG. 18).

[0287] In response to transmitting / performing a first RA preamble / PRACH transmission (e.g., after transmitting / performing a first RA preamble / PRACH transmission, based on transmitting / performing a first RA preamble / PRACH transmission, or during transmitting / performing a first RA preamble / PRACH transmission), the wireless device may, for example, not increment a counter (e.g., a preamble transmission counter, a preamble power ramp counter). In response to transmitting / performing a first RA preamble / PRACH transmission (e.g., after transmitting / performing a first RA preamble / PRACH transmission, based on transmitting / performing a first RA preamble / PRACH transmission, or during transmitting / performing a first RA preamble / PRACH transmission), the wireless device may, for example, maintain (e.g., keep the same, maintain, pause, retain, do not increment, do not decrement, do not add, do not subtract, do not change, etc.) a counter (e.g., maintain the same, maintain, pause, retain, do not increment, do not decrement, do not add, do not subtract, do not change, etc.).

[0288] In the example, the base station (e.g., a base station serving the candidate / target cell, the candidate / target base station, the candidate / target DU / CU, etc.) may not receive the first RA preamble / PRACH transmission. For example, the base station may transmit a second control command (e.g., DCI, PDCCH command) based on the absence of the first RA preamble / PRACH transmission.

[0289] In the example, the radio device receives a second control command (e.g., DCI, PDCCH command). The radio device may receive the second control command (e.g., DCI, PDCCH command) via a source / serving cell (e.g., cell 0 in Figure 18). The radio device may receive the second control command (e.g., DCI, PDCCH command) via a source / serving base station (e.g., source / serving DU). The radio device receives the second control command (e.g., DCI, PDCCH command) in a fourth time interval (e.g., T4 in Figure 18). In the example, T4 may follow T1 / T2 / T3. In the example, T4 may partially / completely overlap with T1 / T2 / T3. In the example, T4 may be the same as T1 / T2 / T3.

[0290] The second control command (e.g., DCI, PDCCH command) instructs the retransmission of the second RA preamble / PRACH transmission. The second control command (e.g., DCI, PDCCH command) can instruct the retransmission of the second RA preamble / PRACH transmission, for example, via a candidate / target cell (e.g., cell 1 in Figure 18) / through the candidate / target cell / on the candidate / target cell / towards the candidate / target cell. As an example, the second RA preamble / PRACH transmission can be the same as the first RA preamble / PRACH transmission. The first RA preamble / PRACH transmission can be associated with (e.g., identified by) a first RA preamble index (e.g., PREAMBLE_INDEX, RA preamble identity, RA preamble identifier, etc.). The second RA preamble / PRACH transmission can be associated with (e.g., identified by) a second RA preamble index (e.g., PREAMBLE_INDEX, RA preamble identity, RA preamble identifier, etc.). The first RA preamble index can be the same as the second RA preamble index, for example. For example, based on the fact that the second RA preamble index is the same as the first RA preamble index, the second RA preamble / PRACH transmission can be the same as the first RA preamble / PRACH transmission.

[0291] The second RA preamble / PRACH transmission may, for example, differ from (e.g., not the same as) the first RA preamble / PRACH transmission. The first RA preamble index may, for example, differ from (e.g., not the same as) the second RA preamble index. For example, based on the difference between the second and first RA preamble indices (e.g., not the same as), the second RA preamble / PRACH transmission may differ from (e.g., not the same as) the first RA preamble / PRACH transmission.

[0292] A second control command (e.g., DCI, PDCCH command) may, for example, trigger / initiate a second RA procedure. The second control command (e.g., DCI, PDCCH command) may, for example, be used in the second RA procedure / be a control command for the second RA procedure / be associated with the second RA procedure. The second RA procedure may, for example, be the same as the first RA procedure. In response to the first RA procedure being the same as the second RA procedure, the wireless device may not initialize / reset counters (e.g., preamble transmission counter, preamble power ramp counter) and / or, for example, one or more parameters / variables in / within the wireless device (e.g., Msg3 buffer, MSGA buffer, PREAMBLE_BACKOFF, POWER_OFFSET_2STEP_RA, etc.). In response to the first RA procedure being the same as the second RA procedure, the wireless device may continue the first RA procedure. In response to the first RA procedure being the same as the second RA procedure, the wireless device may ignore the second control command (e.g., DCI, PDCCH command).

[0293] The second RA procedure may, for example, differ from the first RA procedure (e.g., not be the same).

[0294] The second control command (e.g., DCI, PDCCH command) may include fields (e.g., bit field, multi-bit field, etc.). These fields may indicate retransmission of the second RA preamble / PRACH transmission.

[0295] The second control command (e.g., DCI, PDCCH command) can indicate, for example, the candidate / target cell for the second RA procedure (and / or second RA preamble / PRACH transmission).

[0296] The wireless device may increment a counter (e.g., a preamble transmission counter, a preamble power ramp counter) based, for example, a second control command (e.g., a DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH transmission.

[0297] The wireless device may increment a counter (e.g., a preamble transmission counter, a preamble power ramp counter) based, for example, on a second control command (e.g., a DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH transmission and / or on a first RS for the first RA procedure (or the first RA preamble / PRACH transmission) that is the same as the second RS for the second RA procedure (or the second RA preamble / PRACH transmission). The first RA procedure may, for example, begin before the second RA procedure, begin before the second RA procedure, or complete before the second RA procedure.

[0298] Using RS (e.g., first RS, second RS, etc.) for RA procedures (e.g., first RA procedure, second RA procedure, etc.) may include: determining (e.g., selecting, picking, applying, etc.) the RS for the RA procedure based, for example, on the radio link quality (e.g., reference signal received power, reference signal received quality, received signal strength indicator, block error rate, signal-to-noise ratio, etc.) of one or more RSs including said RS. The one or more configuration parameters may indicate said one or more RSs.

[0299] Using RS for RA procedures may include, for example, determining one or more RA resources based on RS for RA preamble / PRACH transmission of the RA procedure.

[0300] Using RS for RA procedures may include, for example, using / based on RS to determine path loss (e.g., to determine the transmit / transmit power of the RA preamble / PRACH transmission for the RA procedure).

[0301] Using RS for RA procedures can include, for example, determining the beam (e.g., transmit beam, receive beam, spatial domain filter, spatial filter, spatial domain transmit filter, quasi-co-location, quasi-co-location assumption, etc.) for the RA preamble / PRACH transmission used to transmit / execute the RA procedure based on RS.

[0302] In response to an incrementing counter (e.g., a preamble transmission counter, a preamble power ramp counter) (e.g., after the incrementing counter, based on the incrementing counter, during the incrementing counter, etc.), the wireless device can transmit / perform a second RA preamble / PRACH transmission. For example, after the incrementing counter (e.g., a preamble transmission counter, a preamble power ramp counter), the wireless device can, for example, transmit / perform a second RA preamble / PRACH transmission based on the value of the counter (e.g., a preamble transmission counter, a preamble power ramp counter).

[0303] For example, in the example embodiment of Figure 18, the value of the counters (e.g., preamble transmission counter, preamble power ramp counter) before T4 can be a first value. After incrementing (e.g., near T4 / after T4 / in response to T4 / based on T4), the value of the counters (e.g., preamble transmission counter, preamble power ramp counter) can be / have a second value based on the second control command (e.g., DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH transmission. The radio device can transmit / perform the second RA preamble / PRACH transmission via a first candidate / target cell based on the second value of the counters (e.g., preamble transmission counter, preamble power ramp counter). The radio device can also transmit / perform the second RA preamble / PRACH transmission without based on the first value of the counters (e.g., preamble transmission counter, preamble power ramp counter). For example, a wireless device can use the second value in the first equation for a "counter (e.g., a preamble transmission counter, a preamble power ramp counter)".

[0304] The wireless device can utilize / use a second transmit / transmit power to transmit / perform a second RA preamble / PRACH transmission. The wireless device can determine the second transmit / transmit power based on a second value of a counter (e.g., a preamble transmission counter, a preamble power ramp counter). For example, the wireless device can use the second value in the first equation for the "counter (e.g., a preamble transmission counter, a preamble power ramp counter)" to determine the second transmit / transmit power. For example, the wireless device can use the first equation to determine the second transmit / transmit power. The first equation can be / include, for example, second transmit / transmit power (in dB) = min{maximum output power configured by the wireless device, path loss (in dB) + preambleReceivedTargetPower + DELTA_PREAMBLE + (second value - 1) × PREAMBLE_POWER_RAMPING_STEP + POWER_OFFSET_2STEP_RA}.

[0305] In the example, the second value can be less than (or equal to) the first maximum value (e.g., preambleTransMax, preambleTransMax+1). For example, one or more configuration parameters and / or the first candidate / target (LTM cell) configuration can indicate the first maximum value. The first maximum value can be the maximum number of RA preamble / PRACH transmissions (e.g., the maximum allowed number). The radio device can transmit / perform a second RA preamble / PRACH transmission based on the second value being less than (or equal to) the first maximum value. In the example of Figure 18, the radio device transmits / performs a second RA preamble / PRACH transmission. The radio device can transmit / perform a second RA preamble / PRACH transmission during a fifth time interval (e.g., T5 in Figure 18). The wireless device may not increment a counter (e.g., a preamble transmission counter, a preamble power ramp counter) after transmitting / performing a second RA preamble / PRACH transmission (e.g., when transmitting / performing a second RA preamble / PRACH transmission, in response to transmitting / performing a second RA preamble / PRACH transmission, based on transmitting / performing a second RA preamble / PRACH transmission, etc.).

[0306] In the example, the second value can be greater than (or equal to) the first maximum value. The wireless device can choose not to transmit / perform a second RA preamble / PRACH transmission based on the second value being greater than (or equal to) the first maximum value.

[0307] In the example, based on an incrementing counter (e.g., a preamble transmission counter, a preamble power ramp counter) (e.g., after the incrementing counter, while the incrementing counter, in response to the incrementing counter, etc.), the second value can be greater than (or equal to) the first maximum value (e.g., preambleTransMax, preambleTransMax+1). In response to the second value being greater than (or equal to) the first maximum value (e.g., preambleTransMax, preambleTransMax+1), the wireless device can execute one or more procedures. The one or more procedures may include, for example, declaring a radio link failure (RLF) or RA problem. The one or more procedures may include, for example, declaring an ETA / LTM TA acquisition (e.g., early TA acquisition, TA acquisition of the one or more candidate / target cells, etc.) failure. The one or more procedures may include, for example, determining (e.g., considering, assuming, etc.) an RA procedure to be completed (e.g., successfully or unsuccessfully completed) (e.g., a first RA procedure, a second RA procedure, etc.).

[0308] Declaring an RLF or RA problem may include, for example, transmitting an uplink signal indicating an RLF or RA problem to the base station (e.g., via the source / serving cell (cell 0 in Figure 18)). For example, the uplink signal may include one or more fields indicating an RLF or RA problem. These one or more fields may indicate the identity / index / identifier of the candidate / target cell in the one or more candidate / target cells associated with the RA procedure and / or the candidate / target (LTM cell) configuration in the one or more candidate / target (LTM cell) configurations.

[0309] Declaring an ETA / LTM TA acquisition failure (e.g., early TA acquisition, TA acquisition of one or more candidate / target cells, etc.) may include transmitting a second uplink signal (e.g., via the source / serving cell (cell 0 in Figure 18)) to the base station indicating the LTM TA acquisition failure. For example, the second uplink signal may include one or more fields indicating the LTM TA acquisition failure. These one or more fields may indicate the identity / index / identifier of the candidate / target cell in the one or more candidate / target cells associated with the RA procedure and / or the candidate / target (LTM cell) configuration in the one or more candidate / target (LTM cell) configuration.

[0310] The second control command (e.g., DCI, PDCCH command) may, for example, indicate a first candidate / target cell among the one or more candidate / target cells. For example, the second control command (e.g., DCI, PDCCH command) may include a field indicating the first candidate / target cell among the one or more candidate / target cells. For example, the second control command (e.g., DCI, PDCCH command) may include a field in the configuration of the one or more candidate / target (LTM cell) configuration associated with the first candidate / target cell among the one or more candidate / target cells. For example, based on the second control command (e.g., DCI, PDCCH command) indicating the first candidate / target cell among the one or more candidate / target cells, the radio device may transmit / perform a second RA preamble / PRACH transmission via the first candidate / target cell among the one or more candidate / target cells / on the first candidate / target cell among the one or more candidate / target cells / through the first candidate / target cell among the one or more candidate / target cells / for the first candidate / target cell among the one or more candidate / target cells / toward the first candidate / target cell among the one or more candidate / target cells.

[0311] In the prior art, a wireless device can initialize a power ramp counter in response to receiving a PDCCH command initiating an RA procedure. The wireless device can initialize the power ramp counter at the start of the RA procedure. The wireless device can initialize (e.g., initialize to 1) the power ramp counter in response to a PDCCH command indicating initial preamble transmission. The wireless device can increment the power ramp counter in response to a PDCCH command indicating preamble retransmission.

[0312] In the example, the wireless device can receive a first PDCCH command to initiate a first RA procedure. The wireless device can initialize a power ramp counter based on the PDCCH command initiating the first RA procedure. The PDCCH command can indicate a first RA preamble. The wireless device can transmit the first RA preamble to the base station. For example, the base station may not receive the first RA preamble due to insufficient transmission power used by the wireless device.

[0313] The base station can transmit a second PDCCH command to the wireless device. The wireless device can receive the second PDCCH command. The second PDCCH command can initiate a second RA procedure. In prior art implementations, the wireless device can initialize (e.g., initialize to 1) a power ramp counter (e.g., at the start of the second RA procedure or based on receiving the second PDCCH command initiating the second RA procedure). The second PDCCH command can indicate a second RA preamble. The second PDCCH command can indicate preamble retransmission of the second RA preamble. The wireless device can increment (e.g., increment by 1) the power ramp counter based on the second PDCCH command indicating preamble retransmission. The value of the power ramp counter can be 2 (e.g., initial value (1) + increment (increment by 1) = 2). The wireless device can transmit the second RA preamble using the transmission power determined based on the value of the power ramp counter (i.e., 2).

[0314] For example, the base station may not receive the second RA preamble due to insufficient transmission power used by the wireless device.

[0315] The base station can transmit a third PDCCH command to the wireless device. The wireless device can receive the third PDCCH command. The third PDCCH command can initiate a third RA procedure. In prior art implementations, the wireless device can initialize (e.g., initialize to 1) a power ramp counter (e.g., at the start of the third RA procedure or based on receiving the third PDCCH command initiating the third RA procedure). The third PDCCH command can indicate a third RA preamble. The third PDCCH command can indicate preamble retransmission of the third RA preamble. The wireless device can increment (e.g., increment by 1) the power ramp counter based on the third PDCCH command indicating preamble retransmission. The value of the power ramp counter can be 2 (e.g., initial value (1) + increment (increment by 1) = 2). The wireless device can transmit the third RA preamble using the transmission power determined based on the value of the power ramp counter (i.e., 2).

[0316] When a wireless device transmits a third RA preamble using the same transmission power determined by the same power ramp counter that caused the base station to fail to receive the second RA preamble, the base station may not receive the third RA preamble. Similarly, in prior art implementations, one or more upcoming RA preamble transmissions may also fail due to the use of the same power ramp counter value to determine the transmission power used for transmitting the RA preamble. Given the prior art, an improvement to the incrementing power ramp counter is needed when the PDCCH command instructs a preamble retransmission.

[0317] In the example, the wireless device receives a first control command (e.g., a DCI or PDCCH command). The first control command (e.g., a DCI or PDCCH command) may include an index for a first RA preamble / PRACH transmission, an uplink or supplementary uplink indicator, an RS (e.g., an SS / PBCH block, SSB) index, and / or a PRACH mask index indicating the RA channel timing associated with the RS used for the first RA preamble / PRACH transmission.

[0318] In the example, a first control command (e.g., DCI, PDCCH command) can initiate / trigger a first RA procedure (e.g., used for / associated with an LTM / ETA process / procedure). The first RA procedure can be used for one or more candidate / target cells (e.g., cell 1 in Figure 18) / is the RA procedure of the candidate / target cell / associated with the candidate / target cell.

[0319] A first control command (e.g., DCI, PDCCH command) may indicate the initial transmission of a first RA preamble / PRACH. The first control command (e.g., DCI, PDCCH command) may include fields (e.g., bit fields, multi-bit fields, etc.). These fields may indicate the initial transmission of a first RA preamble / PRACH.

[0320] For example, a wireless device can initialize / reset (e.g., non-increment) a counter based on a first control command (e.g., DCI, PDCCH command) indicating the initial transmission of the first RA preamble / PRACH. In this example, the counter could be a preamble power ramp counter (PPRC). The counter can be used to determine the transmit / transmit power used to transmit / perform the RA preamble / PRACH transmission. For example, the wireless device can determine the transmit / transmit power based on a first equation. The first equation could be, for example, transmit / transmit power (in dB) = min{maximum output power configured for the wireless device, path loss (in dB) + preambleReceivedTargetPower + DELTA_PREAMBLE + (counters (e.g., preamble transmission counter, preamble power ramp counter) - 1) × PREAMBLE_POWER_RAMPING_STEP + POWER_OFFSET_2STEP_RA}, wherein one or more configuration parameters and / or the first candidate / target (LTM cell) configuration can indicate preambleReceivedTargetPower, DELTA_PREAMBLE, POWER_OFFSET_2STEP_RA, and PREAMBLE_POWER_RAMPING_STEP}.

[0321] Initializing / resetting a counter (e.g., a preamble power ramp counter) may include setting the value of the counter (e.g., a preamble power ramp counter) to a first value. For example, the first value may be one. For example, the first value may be zero.

[0322] In the example of Figure 18, the wireless device can transmit / perform the first RA preamble / PRACH transmission via a first candidate / target cell at a third time interval T3. T3 can, for example, follow T2.

[0323] The first RA preamble / PRACH transmission can be used / associated with the first RA procedure.

[0324] The wireless device receives a second control command (e.g., DCI, PDCCH command) in a fourth time interval (e.g., T4 in Figure 18). In the example, T4 may be after T3.

[0325] A second control command (e.g., DCI, PDCCH command) may, for example, trigger / initiate a second RA procedure. The second control command (e.g., DCI, PDCCH command) may, for example, be used in the second RA procedure / be a control command for the second RA procedure / be associated with the second RA procedure. The first RA procedure may, for example, be completed before the second RA procedure. The second RA procedure may, for example, be different from the first RA procedure (e.g., not identical).

[0326] The second control command (e.g., DCI, PDCCH command) may include fields (e.g., bit field, multi-bit field, etc.). These fields may indicate retransmission of the second RA preamble / PRACH transmission.

[0327] The second control command (e.g., DCI, PDCCH command) can indicate, for example, the candidate / target cell for the second RA procedure (and / or second RA preamble / PRACH transmission).

[0328] The wireless device may increment a counter (e.g., a preamble power ramp counter) based, for example, a second control command (e.g., a DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH transmission.

[0329] For example, in the example embodiment of Figure 18, the value of the counter (e.g., the preamble power ramp counter) before T4 can be a first value. The value of the counter (e.g., the preamble power ramp counter) after the increment (e.g., at T4 / near T4 / after T4 / in response to T4 / based on T4) can be / have a second value. The radio device can transmit / perform a second RA preamble / PRACH transmission based on the second value of the counter (e.g., the preamble power ramp counter) via a first candidate / target cell. The radio device can also transmit / perform a second RA preamble / PRACH transmission without basing it on the first value of the counter (e.g., the preamble power ramp counter). For example, the radio device can use the second value in the first equation for the "counter (e.g., the preamble power ramp counter)".

[0330] The wireless device can utilize / use a second transmit / transmit power to transmit / perform a second RA preamble / PRACH transmission. The wireless device can determine the second transmit / transmit power based on a second value of a counter (e.g., a preamble power ramp counter). For example, the wireless device can use the second value in the first equation for the "counter (e.g., preamble power ramp counter)" to determine the second transmit / transmit power. For example, the wireless device can use the first equation to determine the second transmit / transmit power. The first equation can be / include, for example, second transmit / transmit power (in dB) = min{maximum output power configured by the wireless device, path loss (in dB) + preambleReceivedTargetPower + DELTA_PREAMBLE + (second value - 1) × PREAMBLE_POWER_RAMPING_STEP + POWER_OFFSET_2STEP_RA}.

[0331] Figure 19 shows an example flowchart of an embodiment according to the present disclosure.

[0332] According to the embodiment in Figure 19, in response to receiving a second control command (e.g., DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH transmission, the wireless device can determine whether to increment a counter (e.g., preamble transmission counter, preamble power ramp counter) based on the listen-before-talk (LBT) indication / failure / success of the first RA preamble / PRACH transmission.

[0333] A wireless device may apply LBT before performing a transmission (e.g., a first RA preamble / PRACH transmission) on / via a first candidate / target cell. For example, the first candidate / target cell may be configured to have shared spectrum channel access. When LBT is applied, the transmitter (e.g., the wireless device, base station, etc.) may listen to (e.g., sense) the channel to determine whether it is idle or busy. The wireless device may (e.g., only) perform a transmission if the channel is sensed to be idle. For example, if / in response to / based on the channel being sensed to be busy, the wireless device may be unable to access the channel (e.g., it may determine that LBT has failed or an LBT failure indication has been given).

[0334] In the example, the wireless device (e.g., the MAC entity / layer of the wireless device) can determine (e.g., instruct a lower layer / physical layer of the wireless device) to transmit / perform a first RA preamble / PRACH transmission. For example, before transmitting / performing the first RA preamble / PRACH transmission, the wireless device may be unable to access the channel (e.g., PRACH). The wireless device can determine an LBT failure / failure indication for the first RA preamble / PRACH transmission. For example, the lower / physical layer of the wireless device can instruct / transmit / send / provide an LBT failure indication for the first RA preamble / PRACH transmission to the higher / MAC entity / layer of the wireless device.

[0335] In response to a second control command (e.g., DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH transmission, the wireless device may not increment (e.g., maintain, hold, keep the same, pause, hold, etc.) a counter (e.g., preamble transmission counter, preamble power ramp counter) based, for example, on determining an LBT failure / failure indication for the first RA preamble / PRACH transmission. For example, in response to a second control command (e.g., DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH transmission, the wireless device may not increment a counter (e.g., preamble transmission counter, preamble power ramp counter) based on receiving an LBT failure indication (e.g., from a lower layer / physical layer of the wireless device) for / associated with / corresponding to the first RA preamble / PRACH transmission.

[0336] In another example, for instance, the wireless device may successfully access the channel (e.g., PRACH) before transmitting / performing the first RA preamble / PRACH transmission. The wireless device may not be certain about LBT failure / failure indications for the first RA preamble / PRACH transmission. For example, the lower / physical layer of the wireless device may not indicate / transmit / send / provide an LBT failure indication for the first RA preamble / PRACH transmission to / from / to / provide it to / from / to ...

[0337] In response to a second control command (e.g., DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH transmission, the wireless device may increment a counter (e.g., a preamble transmission counter, a preamble power ramp counter) based on, for example, the absence of an LBT failure / failure indication for determining the first RA preamble / PRACH transmission (e.g., based on successful channel access before transmitting / performing the first RA preamble / PRACH transmission / for transmitting / performing the first RA preamble / PRACH transmission / before transmitting / performing the first RA preamble / PRACH transmission, and / or based on the absence of an LBT failure indication received from a lower layer (e.g., the physical layer) of the wireless device. For example, in response to a second control command (e.g., DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH transmission, the wireless device may increment a counter (e.g., preamble transmission counter, preamble power ramp counter) based on the absence of an LBT failure indication (e.g., from a lower layer / physical layer of the wireless device) for / associated with / corresponding to the first RA preamble / PRACH transmission (e.g., based on previous unsuccessful access to (or non-access to) the channel).

[0338] Incrementing counters (e.g., preamble transmission counters, preamble power ramp counters) based on a second control command (e.g., DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH transmission, regardless of LBT failure indications, may not be suitable for LTM operation with shared spectrum channel access. In scenarios where LTM is not used with shared spectrum channel access, incrementing counters (e.g., preamble transmission counters, preamble power ramp counters) based on a second control command (e.g., DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH transmission, regardless of LBT failure indications, may be appropriate because the base station can control the retransmission of the RA preamble / PRACH transmission (e.g., the radio device may not autonomously retransmit the RA preamble / PRACH transmission). If the base station does not receive the RA preamble / PRACH transmission, it may not know whether the lack of reception is due to low power usage by the radio device or the radio device failing to transmit the RA preamble / PRACH transmission due to LBT failure. (Therefore) the wireless device can determine whether to increment or not increment a counter (e.g., preamble transmission counter, preamble power ramp counter) in response to receiving a second control command (e.g., DCI, PDCCH command) indicating a retransmission of the RA preamble / PRACH transmission, based on the LBT failure / LBT failure indication associated with the first RA preamble / PRACH transmission / the first RA preamble / PRACH transmission / for the first RA preamble / PRACH transmission.

[0339] Figure 20 shows an example flowchart of an embodiment according to the present disclosure.

[0340] According to the embodiment in FIG20, in response to receiving (e.g., if, based on, after, etc.) a second control command (e.g., DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH, the wireless device may determine whether to increment the counter (e.g., preamble transmission counter, preamble power ramp counter) based on whether the counter (e.g., preamble transmission counter, preamble power ramp counter) is paused (as determined by the wireless device).

[0341] In the example, the wireless device may use / utilize a first spatial domain transmission filter to transmit / perform a first RA preamble / PRACH transmission. The wireless device may determine a second spatial domain transmission filter for transmitting / performing a second RA preamble / PRACH transmission.

[0342] In the example, the first spatial domain transmission filter may be different from the second spatial domain transmission filter (e.g., not the same). For example, based on the difference between the first and second spatial domain transmission filters (e.g., not the same), the wireless device may determine a pause counter (e.g., a preamble transmission counter, a preamble power ramp counter) before transmitting / performing the second RA preamble / PRACH transmission.

[0343] In the example, the wireless device may determine to transmit / perform a first RA preamble / PRACH transmission. The wireless device may, for example, refrain from transmitting / performing a first RA preamble / PRACH transmission based on: power allocation for PUSCH / PUCCH / PRACH / SRS transmissions, power allocation in EN-DC, NE-DC, or NR-DC operation, time slot format determination, PUSCH / PUCCH / PRACH / SRS transmissions occurring in the same time slot, or a small gap between the first RA preamble / PRACH transmission and the PUSCH / PUCCH / SRS transmission, and / or HD-UE operation in the paired spectrum. For example, based on refraining from transmitting / performing a first RA preamble / PRACH transmission, the wireless device may determine a pause counter (e.g., a preamble transmission counter, a preamble power ramp counter).

[0344] In response to / based on receiving a second control command (e.g., DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH, the wireless device may, for example, determine a pause counter (e.g., preamble transmission counter, preamble power ramp counter) without incrementing (e.g., maintaining, keeping the same value, holding, sustaining, pausing, etc.) the counter (e.g., preamble transmission counter, preamble power ramp counter).

[0345] The wireless device may increment a counter (e.g., a preamble transmission counter, a preamble power ramp counter) based on, for example, the following (e.g., in response to, when, or if): a second control command (e.g., a DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH transmission; the first RS for the first RA procedure (or the first RA preamble / PRACH transmission) being the same as the second RS for the second RA procedure (or the second RA preamble / PRACH transmission); no listen-before-tell (LBT) failure indication received from the lower layer for the first RA preamble / PRACH transmission (e.g., no LBT failure for the first RA preamble / PRACH transmission); and / or no notification received from the lower layer of the wireless device of a pause counter (e.g., a preamble transmission counter, a preamble power ramp counter) (e.g., the wireless device has not determined a pause counter (e.g., a preamble transmission counter, a preamble power ramp counter)). For example, if any of the above conditions (in this paragraph) are not met, the wireless device may not increment the counter (e.g., preamble transmission counter, preamble power ramp counter).

[0346] In some embodiments, the example embodiments of Figures 19 and 20 can be combined. For example, in response to receiving a second control command (e.g., DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH transmission, the wireless device can determine an incrementing counter (e.g., a preamble transmission counter, a preamble power ramp counter) based on: the determination of an LBT failure / LBT failure indication for / associated with the first RA preamble / PRACH transmission, and / or a pause counter (e.g., a preamble transmission counter, a preamble power ramp counter).

[0347] In this disclosure, a counter can refer to, for example, a preamble transmission counter. For instance, a preamble transmission counter can be used to count / track / determine the number of RA preamble / PRACH transmissions. A preamble transmission counter can also be used to count / track / determine the number of unsuccessful / failed RA preamble / PRACH transmissions (e.g., not decoded or acknowledged by the base station, or not received a response associated with / corresponding to the RA preamble / PRACH transmission (e.g., an RA response)).

[0348] In this disclosure, a counter can refer to, for example, a preamble power ramp counter.

[0349] In this disclosure, LTM and LTM procedure / process are used interchangeably. In some embodiments, LTM and LTM procedure / process may refer to the same thing.

[0350] In this disclosure, control commands (e.g., DCI, PDCCH commands) can refer to / refer to PDCCH commands. Control commands (e.g., DCI, PDCCH commands) can be, for example, DCI format X_Y, where X = {0, 1, 2, 3…} and Y = {0, 1, 2, 3…}. In some embodiments, control commands can be / include MAC CE, Layer 1 messages / commands (e.g., PDCCH, PDSCH, etc.), Layer 2 messages / commands (e.g., MAC CE), and / or Layer 3 messages / commands (e.g., RRC messages).

[0351] In this disclosure, retransmission of an RA preamble / PRACH transmission can refer to retransmission of the same or different RA preamble / PRACH transmissions. For example, an initial RA preamble / PRACH transmission may include performing / transmitting a first RA preamble / PRACH transmission. Retransmission of an RA preamble / PRACH transmission may include performing / transmitting a second RA preamble / PRACH transmission. In the example, the first RA preamble / PRACH transmission may be the same as the second RA preamble / PRACH transmission. In the example, the second RA preamble / PRACH transmission may be different from the first RA preamble / PRACH transmission (e.g., not identical). Retransmission can indicate that the RA preamble is transmitted again for the same RA procedure / process or purpose. For example, the first RA preamble / PRACH transmission and the second RA preamble / PRACH transmission may be used for / belong to the same RA procedure. For example, the first RA preamble / PRACH transmission and the second RA preamble / PRACH transmission can be used for the same purpose (e.g., early TA acquisition in LTM, beam fault recovery, TA acquisition, LTM procedure, etc.).

[0352] In this disclosure, an incrementing counter (e.g., a preamble transmission counter, a preamble power ramp counter) may include incrementing the value of the counter (e.g., a preamble transmission counter, a preamble power ramp counter) by, for example, a first number. The first number may be one. The first number may be greater than one (e.g., 2, 3, 4, ...). An incrementing counter (e.g., a preamble transmission counter, a preamble power ramp counter) may, for example, include a non-maintaining counter (e.g., a preamble transmission counter, a preamble power ramp counter). An incrementing counter (e.g., a preamble transmission counter, a preamble power ramp counter) may, for example, include a non-decrementing counter (e.g., a preamble transmission counter, a preamble power ramp counter).

[0353] In some embodiments of this disclosure, a sustain counter (e.g., a preamble transmission counter, a preamble power ramp counter) may refer to / including a non-incrementing (e.g., remain the same, retain, maintain, do not change, pause, etc.) counter (e.g., a preamble transmission counter, a preamble power ramp counter). In some embodiments, a sustain counter (e.g., a preamble transmission counter, a preamble power ramp counter) may refer to / including an initialization / reset counter (e.g., a preamble transmission counter, a preamble power ramp counter).

[0354] In the example, if the RA procedure is initiated by a control command (e.g., DCI, PDCCH command) and the control command (e.g., DCI, PDCCH command) instructs (e.g., RA preamble) to retransmit, the wireless device (or the wireless device's MAC entity) can increment a counter (e.g., preamble transmission counter, preamble power ramp counter) by 1. If the counter (e.g., preamble transmission counter, preamble power ramp counter) equals preambleTransMax + 1, the wireless device can determine (e.g., consider) that the RA procedure did not complete successfully. If the RA procedure did not complete, the wireless device can transmit the RA preamble / PRACH transmission (e.g., instructing the lower layer / physical layer to transmit the RA preamble / PRACH transmission).

[0355] Figure 21 illustrates an example flowchart of an embodiment according to this disclosure. According to the example of Figure 21, a wireless device may receive one or more configuration parameters from a base station (e.g., via a source / serving cell). The one or more configuration parameters may include one or more candidate / target (LTM cell) configurations. The one or more candidate / target (LTM cell) configurations may be used for / are used for an LTM procedure. The one or more candidate / target (LTM cell) configurations may be associated with / correspond to / are for / are for / are one or more candidate / target cells (e.g., for LTM). Each candidate / target (LTM cell) configuration in the one or more candidate / target (LTM cell) configurations may be associated with / correspond to / are for ...

[0356] The wireless device can receive control commands (e.g., DCI, PDCCH commands). The wireless device can receive control commands (e.g., DCI, PDCCH commands) for example, after receiving the one or more configuration parameters. The control commands (e.g., DCI, PDCCH commands) can instruct the transmission of RA preamble / PRACH transmissions (e.g., initial transmission or retransmission). The control commands (e.g., DCI, PDCCH commands) can instruct transmissions via one or more candidate / target cells, through the candidate / target cell, or the candidate / target cell's RA preamble / PRACH transmission for the candidate / target cell.

[0357] In the example, control commands (e.g., DCI, PDCCH commands) can indicate an initial transmission via a candidate / target cell / through a candidate / target cell / of a candidate / target cell / for a candidate / target cell's RA preamble / PRACH. For instance, based on the control commands (e.g., DCI, PDCCH commands) indicating an initial transmission via one or more candidate / target cells / through a candidate / target cell / of a candidate / target cell / for a candidate / target cell's RA preamble / PRACH, the radio device may not increment (e.g., may maintain, may reset / initialize) counters (e.g., preamble transmission counter, preamble power ramp counter).

[0358] In the example, control commands (e.g., DCI, PDCCH commands) can instruct retransmissions via candidate / target cell / through candidate / target cell / of candidate / target cell / for candidate / target cell RA preamble / PRACH transmission. The radio device can increment a counter (e.g., preamble transmission counter, preamble power ramp counter) based, for example, on the control commands (e.g., DCI, PDCCH commands) instructing retransmissions via candidate / target cell / through candidate / target cell / of candidate / target cell / for candidate / target cell RA preamble / PRACH transmission. The radio device can transmit / perform RA preamble / PRACH transmission, for example, after incrementing the counter (e.g., preamble transmission counter, preamble power ramp counter). The radio device can transmit / perform RA preamble / PRACH transmission, for example, via candidate / target cell / through candidate / target cell / on candidate / target cell.

[0359] An example method includes: receiving one or more Radio Resource Control (RRC) messages by a wireless device, the RRC messages including configuration parameters for one or more candidate target cells for a mobility (LTM) procedure triggered at Layer 1 and Layer 2; receiving a control command indicating a retransmission of RA preamble / PRACH transmission via one or more candidate target cells; incrementing a counter (e.g., a preamble transmission counter, a preamble power ramp counter) in response to the control command indicating the retransmission of RA preamble / PRACH transmission (e.g., a DCI, PDCCH command); and transmitting the RA preamble / PRACH transmission after incrementing.

[0360] The example method described above may also include receiving a second control command (e.g., DCI, PDCCH command).

[0361] One or more of the above example methods, wherein the second control command (e.g., DCI, PDCCH command) indicates the initial transmission of the second RA preamble for the second RA procedure.

[0362] One or more of the above example methods further include: not incrementing the preamble transmission counter based on a second control command (e.g., DCI, PDCCH command) indicating the initial transmission of the second RA preamble for the second RA procedure.

[0363] One or more of the above example methods, wherein the control command (e.g., DCI, PDCCH command) includes a one-bit field indicating the retransmission of the RA preamble.

[0364] One or more of the above example methods, wherein the second control command (e.g., DCI, PDCCH command) includes a one-bit field indicating the initial transmission of the second RA preamble.

[0365] One or more of the above example methods, wherein the transmission is performed at a first transmission power.

[0366] In one or more of the above example methods, the first transmission power is determined based on a power ramp counter.

[0367] One or more of the above example methods also include incrementing the power ramp counter based on control commands (e.g., DCI, PDCCH commands) indicating retransmission of the RA preamble.

[0368] One or more of the above example methods, wherein the transmission is used for the RA program.

[0369] One or more of the above example methods also include incrementing the power ramp counter based on: control commands (e.g., DCI, PDCCH commands) indicating the retransmission of the RA preamble; and the RS of the RA procedure being the same for the retransmission of the RA preamble and the previous transmission of the second RA preamble.

[0370] One or more of the above example methods, wherein the transmission is based on the preamble transmission counter being less than the number of RA preamble transmissions.

[0371] One or more of the above example methods, wherein the configuration parameter indicates the number of RA preamble transmissions.

[0372] One or more of the above example methods, where the number of RA preamble transmissions is preambleTransMax.

[0373] One or more of the above example methods, wherein the one or more RRC messages are one or more RRC reconfiguration messages.

[0374] In one or more of the above example methods, the control commands (e.g., DCI, PDCCH commands) are physical control channel commands.

[0375] In one or more of the above example methods, the control command (e.g., DCI, PDCCH command) indicates at least one or more of the following: the index of the RA preamble; the reference signal for the RA procedure; and / or the mask index.

[0376] One or more of the above example methods also include setting the preamble transmission counter to a first value before receiving a control command (e.g., DCI, PDCCH command).

[0377] One or more of the above example methods, where the first value is one / zero.

[0378] One or more of the above example methods also include receiving a third control command (e.g., DCI, PDCCH command) that indicates a retransmission of the third RA preamble.

[0379] One or more of the above example methods also include incrementing the preamble transmission counter in response to a third control command (e.g., DCI, PDCCH command) indicating a retransmission of the third RA preamble.

[0380] In one or more of the above example methods, after the preamble transmission counter is incremented in response to a third control command (e.g., DCI, PDCCH command) indicating a retransmission of the third RA preamble, the preamble transmission counter is equal to the number of RA preamble transmissions.

[0381] One or more of the above example methods also include transmitting a UL message to the base station indicating that the RA procedure has failed.

[0382] One or more of the above example methods also include failing to complete the RA procedure.

[0383] An example method includes: transmitting one or more Radio Resource Control (RRC) messages from a (source / serving) base station to a radio device, the RRC messages including configuration parameters for one or more candidate target cells for a mobility (LTM) procedure triggered at Layer 1 and Layer 2; transmitting a control command (e.g., DCI, PDCCH command) indicating retransmission of the RA preamble via one or more candidate target cells; incrementing a preamble transmission counter in response to transmitting the control command (e.g., DCI, PDCCH command) indicating retransmission of the RA preamble via one or more candidate / target cells; and receiving the RA preamble via one or more candidate / target cells.

[0384] Figure 22 illustrates an example timing diagram according to one aspect of an embodiment of the present disclosure. In the example of Figure 22, a radio device (e.g., the UE in Figure 22) may receive a first control command (e.g., a DCI, PDCCH command). The radio device may receive the first control command (e.g., the DCI, PDCCH command) at a first time interval (e.g., T1 as shown in Figure 22). The radio device may receive the first control command (e.g., the DCI, PDCCH command) via a source / serving cell (e.g., cell 0 in Figure 22) / from the source / serving cell / through the source / serving cell. The first control command (e.g., the DCI, PDCCH command) may instruct the transmission (e.g., initial transmission or retransmission) of a first RA preamble / PRACH transmission. The first RA preamble / PRACH transmission and / or the first control command (e.g., the DCI, PDCCH command) may be used / associated with a first RA procedure. In response to receiving the control command (e.g., the DCI, PDCCH command), the radio device may transmit / execute the first RA preamble / PRACH transmission. The wireless device can transmit / perform a first RA preamble / PRACH transmission via one or more candidate / target cells (e.g., cell 1 in FIG22) / for said candidate / target cell / on said candidate / target cell / through said candidate / target cell. In the example of FIG22, the wireless device can transmit / perform the first RA preamble / PRACH transmission during a second time interval (e.g., T2 in FIG22).

[0385] In the example, the first control command (e.g., DCI, PDCCH command) can indicate the initial transmission of the first RA preamble / PRACH. In response to the control command (e.g., DCI, PDCCH command) indicating the initial transmission of the first RA preamble / PRACH, the wireless device may not increment (e.g., it may maintain, initialize, reset, etc.) a counter (e.g., preamble transmission counter, preamble power ramp counter). In the example, the first control command (e.g., DCI, PDCCH command) can indicate the retransmission of the first RA preamble / PRACH. In response to the control command (e.g., DCI, PDCCH command) indicating the retransmission of the first RA preamble / PRACH, the wireless device may increment a counter (e.g., preamble transmission counter, preamble power ramp counter). The value of the incremented counter (e.g., preamble transmission counter, preamble power ramp counter) can be a first value (e.g., 2, 3, 4, ...).

[0386] In the example of Figure 22, a base station (e.g., a source / serving base station, a base station serving a source / serving cell, etc.) can transmit (e.g., via the source / serving cell) a second control command (e.g., a DCI, PDCCH command). The second control command (e.g., a DCI, PDCCH command) can indicate the initial transmission of a second RA preamble / PRACH. The radio device may not receive the second control command (e.g., a DCI, PDCCH command). For example, the radio device may miss (receive) the second control command (e.g., a DCI, PDCCH command). The radio device may not receive the second control command (e.g., a DCI, PDCCH command) for example, based on missing the second control command (e.g., a DCI, PDCCH command). For example, the radio device may not receive the second control command (e.g., a DCI, PDCCH command) because the channel (e.g., PDCCH) carrying the second control command (e.g., a DCI, PDCCH command) experiences poor channel conditions (e.g., insufficient transmission power to offset channel attenuation, poor channel conditions such as shadowing, path loss, scattering, etc.). Based on the absence of a second control command (e.g., DCI, PDCCH command) indicating the initial transmission of the second RA preamble / PRACH, the radio device may not transmit / execute the second RA preamble / PRACH transmission. Based on the radio device's failure to transmit / execute the second RA preamble / PRACH transmission, the base station may not receive the second RA preamble / PRACH transmission. For example, the base station may transmit a third control command (e.g., DCI, PDCCH command) based on the absence of the second RA preamble / PRACH transmission.

[0387] In the example of Figure 22, the wireless device may receive a third control command (e.g., DCI, PDCCH command) during a third time interval (e.g., T3 in Figure 22). T3 may, for example, follow T2. The third control command (e.g., DCI, PDCCH command) may indicate a retransmission of the third RA preamble / PRACH transmission. In the example, the third RA preamble / PRACH transmission may differ from the second RA preamble / PRACH transmission. In the example, the third RA preamble / PRACH transmission may be the same as the second RA preamble / PRACH transmission.

[0388] In existing implementations, in response to a third control command (e.g., DCI, PDCCH command) indicating a retransmission of the third RA preamble / PRACH, the wireless device can increment the power ramp counter.

[0389] After incrementing the power ramp counter, the value of the power ramp counter can be a second value. The second value can be, for example, a sum of the first value. The wireless device can use the power ramp counter (e.g., the second value) to determine the transmit / transmit power used for transmitting / performing the third RA preamble / PRACH transmission.

[0390] Prior art implementations may result in the wireless device using excessive (e.g., more than required, more than expected, more than necessary, etc.) transmit / transmit power to transmit / perform a third RA preamble / PRACH transmission. For example, if the wireless device does not receive a second control command (e.g., DCI, PDCCH command) indicating an initial transmission (of the second RA preamble / PRACH), the wireless device may not reset / initialize (e.g., reset / initialize to zero / one) the preamble power ramp counter. Based on not resetting / initializing (e.g., resetting / initializing to zero / one) the preamble power ramp counter, the counter value may (still) be the first value. Based on incrementing the preamble power ramp counter in response to receiving a retransmission of a third control command (e.g., DCI, PDCCH command) indicating a third RA preamble / PRACH transmission, the wireless device may increment the preamble power ramp counter from the first value to the second value without resetting / initializing the preamble power ramp counter. This can cause wireless devices to use excessive (e.g., more than required, more than expected, more than necessary, etc.) transmit / transmit power to transmit / perform third RA preamble / PRACH transmissions. Excessive (e.g., more than required, more than expected, more than necessary, etc.) transmit / transmit power to transmit / perform third RA preamble / PRACH transmissions can lead to increased power consumption at the wireless device, reduced battery life of the wireless device, and / or increased interference between wireless devices in a cellular network.

[0391] Embodiments of this disclosure relate to a method for determining the value of a counter (e.g., a preamble transmission counter, a preamble power ramp counter) when a control command (e.g., a DCI, PDCCH command) instructs the initiation / retransmission of a RA preamble / PRACH transmission (e.g., for LTM / ETA / RA).

[0392] In an example embodiment, the wireless device may receive control commands (e.g., DCI, PDCCH commands) instructing retransmissions of RA preamble / PRACH transmissions. The control commands (e.g., DCI, PDCCH commands) may include fields indicating the identity of the RA / LTM / ETA procedure (e.g., for RA preamble / PRACH transmissions). The wireless device may determine the value of a counter (e.g., a preamble transmission counter, a preamble power ramp counter) based, for example, on the control commands (e.g., DCI, PDCCH commands) instructing retransmissions of RA preamble / PRACH transmissions and / or the fields. In the example, the fields may indicate the retransmission for RA preamble / PRACH transmission / the retransmission / the first RA / LTM / ETA procedure associated with the retransmission (e.g., the identity of the first RA procedure). The wireless device can compare the field or RA / LTM / ETA procedure (e.g., the identity of the first RA / LTM / ETA procedure) with a previous field / RA procedure (e.g., the identity of the first RA procedure), which is associated, for example, with a previous RA preamble / PRACH transmission (e.g., a first RA preamble / PRACH transmission immediately preceding the RA preamble / PRACH transmission). The wireless device can increment a counter (e.g., a preamble transmission counter, a preamble power ramp counter) based, for example, on fields indicating the same RA / LTM / ETA procedure as the previous RA / LTM / ETA procedure (e.g., fields in control commands (e.g., DCI, PDCCH commands) that are identical to fields in previous control commands (e.g., DCI, PDCCH commands)).

[0393] When control commands (e.g., DCI, PDCCH commands) instruct the initiation or retransmission of an RA preamble / PRACH transmission, example embodiments of this disclosure can provide enhancements for determining the transmit / transmit power for the RA preamble / PRACH transmission. By using example embodiments of this disclosure, a wireless device can avoid using transmit / transmit power higher than required for the RA preamble / PRACH transmission (e.g., it can use the correct transmit / transmit power). Avoiding transmit / transmit power higher than required for the RA preamble / PRACH transmission can improve the battery life of the wireless device, reduce the power consumption of the wireless device, and / or reduce interference between wireless devices (transmissions) including the wireless device in a cellular network.

[0394] Figure 23 illustrates an example timing diagram of one aspect of an embodiment according to the present disclosure. In the example of Figure 23, a wireless device may receive one or more messages. The wireless device may receive the one or more messages from a base station (e.g., a source / serving base station, a base station serving a source / serving cell, e.g., cell 0 in Figure 23). The one or more messages may be similar to / include one or more messages as in the example embodiments of Figures 17 and / or 18. The one or more messages may include one or more configuration parameters. The one or more messages and / or the one or more configuration parameters may include one or more candidate / target (LTM cell) configurations (e.g., one or more candidate / target (LTM cell) configuration parameters). The wireless device may receive the one or more messages, the one or more configuration parameters, and / or the one or more candidate / target (LTM cell) configurations via a source / serving cell (e.g., cell 0 in Figure 23).

[0395] The one or more candidate / target (LTM cell) configurations may include a first candidate / target (LTM cell) configuration. The one or more candidate / target (LTM cell) configurations may include a second candidate / target (LTM cell) configuration. The one or more candidate / target (LTM cell) configurations may be used to indicate one or more candidate / target cells (e.g., for LTM procedures). The one or more candidate / target cells may include a first candidate / target cell. The one or more candidate / target cells may include a second candidate / target cell. The first candidate / target (LTM cell) configuration may be used to / associated with a first candidate / target cell. The second candidate / target (LTM cell) configuration may be used to / associated with a second candidate / target cell.

[0396] In the example of Figure 23, the radio device (e.g., the UE in Figure 23) can receive a first control command (e.g., a DCI or PDCCH command). The radio device can receive the first control command (e.g., a DCI or PDCCH command) from a source / serving base station. The radio device can receive the first control command (e.g., a DCI or PDCCH command) via a source / serving cell (e.g., cell 0 in Figure 23), through the source / serving cell, on the source / serving cell, or from the source / serving cell. The radio device can receive the first control command (e.g., a DCI or PDCCH command) at a first time interval (e.g., T1 in Figure 23). The first control command (e.g., a DCI or PDCCH command) can indicate the transmission (e.g., initial transmission or retransmission) of a first RA preamble / PRACH transmission.

[0397] In response to receiving a first control command (e.g., DCI, PDCCH command) instructing the transmission of a first RA preamble / PRACH, the wireless device can transmit / execute the first RA preamble / PRACH transmission. In the example of Figure 23, the wireless device can transmit / execute the first RA preamble / PRACH transmission at a second time interval T2. In this example, T2 can be after T1.

[0398] The source / serving base station may transmit a second control command (e.g., DCI, PDCCH command) indicating a transmission (e.g., initial transmission or retransmission) such as a second RA preamble / PRACH transmission. The radio device may choose not to receive the second control command (e.g., DCI, PDCCH command). For example, the radio device may not receive the second control command (e.g., DCI, PDCCH command) for instance, based on missing the second control command (e.g., DCI, PDCCH command). For example, the radio device may not receive the second control command (e.g., DCI, PDCCH command) based on the source / serving base station transmitting the second control command (e.g., DCI, PDCCH command) with low / insufficient transmit / transmit power.

[0399] The source / serving base station may transmit third control commands (e.g., DCI, PDCCH commands). The radio device may receive the third control commands (e.g., DCI, PDCCH commands). The radio device may receive the third control commands (e.g., DCI, PDCCH commands) for example at a third time interval (e.g., T3 in Figure 23).

[0400] In example embodiments, the third control command (e.g., DCI, PDCCH command) may include fields indicating procedures / processes (e.g., RA process indicator, LTM process indicator, ETA process indicator, ETA indicator, candidate indicator, etc.). The fields indicating procedures / processes may, for example, indicate a first procedure / process. In the example, the first procedure / process may be / include a first RA procedure / process. In the example, the first procedure / process may be / include a first LTM procedure / process. In the example, the first procedure / process may be / include a first ETA procedure / process.

[0401] Fields indicating procedures / programs can, for example, indicate the identity of the first procedure / program (e.g., 0, 1, 2, 3, etc.).

[0402] In the example, the field can indicate whether a first process / procedure is the same as a previous process / procedure. For example, the field indicating a process / procedure may include bits. For example, based on bit switching, the field can indicate whether a first process / procedure is the same as a previous process / procedure. For example, the bit used / associated with the previous process / procedure can be 0 (or 1). For example, based on the bits used / associated with the first process / procedure and the previous process / procedure being the same (e.g., 0 (or 1)), the first process / procedure can be the same as the previous process. For example, the bit used / associated with the previous process / procedure can be 0 (or 1). For example, based on the bits used / associated with the first process / procedure and the previous process / procedure being different (e.g., 1 (or 0)), the first process / procedure can be the same as the previous process.

[0403] In the example, a first control command (e.g., DCI, PDCCH command) may include a first field indicating a first process / procedure. A third control command (e.g., DCI, PDCCH command) may include a second field indicating a second process / procedure. The first field may include a first bit. The second field includes a second bit. In the example, the first bit may be the same as the second bit. For example, based on the first and second bits being the same, the first control command (e.g., DCI, PDCCH command) (and / or the first field) and the third control command (e.g., DCI, PDCCH command) (and / or the second field) may indicate the same process / procedure (e.g., LTM / ETA / RA process / procedure). For example, based on the second bit not switching from the first bit, the first control command (e.g., DCI, PDCCH command) (and / or the first field) and the third control command (e.g., DCI, PDCCH command) (and / or the second field) may indicate the same process / procedure (e.g., LTM / ETA / RA process / procedure).

[0404] In another example, the first bit can be different from the second bit (e.g., not the same). For example, based on the difference between the first and second bits, a first control command (e.g., DCI, PDCCH command) (and / or the first field) and a third control command (e.g., DCI, PDCCH command) (and / or the second field) can indicate different processes / procedures (e.g., LTM / ETA / RA processes / procedures). For example, based on the second bit switching from the first bit, a first control command (e.g., DCI, PDCCH command) (and / or the first field) and a third control command (e.g., DCI, PDCCH command) (and / or the second field) can indicate the same / different processes / procedures (e.g., LTM / ETA / RA processes / procedures).

[0405] In an example embodiment, the wireless device may determine an incrementing counter (e.g., a preamble transmission counter, a preamble power ramp counter) based on whether the first process / procedure is the same as the second process / procedure (e.g., based on whether the first bit is the same as the second bit).

[0406] In the example of Figure 23, the first bit can be different from the second bit. For example, the first control command (e.g., DCI, PDCCH command) can indicate the first process / procedure. The third control command (e.g., DCI, PDCCH command) can indicate the second process / procedure. The first process / procedure can be different from the second process / procedure. For example, based on the determination that the first process / procedure is different from the second process / procedure, the wireless device may not increment the counter (e.g., preamble transmission counter, preamble power ramp counter).

[0407] A third control command (e.g., DCI, PDCCH command) can instruct the transmission (e.g., initial transmission or retransmission) of the third RA preamble / PRACH transmission. The wireless device can transmit / perform the third RA preamble / PRACH transmission, for example, based on a counter (e.g., preamble transmission counter, preamble power ramp counter). For example, the wireless device can use the value of the counter (e.g., preamble transmission counter, preamble power ramp counter) in the first equation to determine the transmit / transmit power used for transmitting / performing the third RA preamble / PRACH transmission. The wireless device can, for example, perform / transmit the third RA preamble / PRACH transmission during a fourth time interval (e.g., T4 shown in Figure 23).

[0408] Figure 24 illustrates an example timing diagram of one aspect of an embodiment according to the present disclosure. In the example of Figure 24, the wireless device may receive a first control command (e.g., DCI, PDCCH command) (e.g., at a first time interval T1). The first control command (e.g., DCI, PDCCH command) in Figure 24 may be the same as the first control command (e.g., DCI, PDCCH command) in the embodiment shown in Figure 23. The first control command (e.g., DCI, PDCCH command) may indicate a first procedure. The first control command (e.g., DCI, PDCCH command) may indicate the transmission (e.g., initial transmission or retransmission) of a first RA preamble / PRACH transmission. The wireless device may, for example, transmit / perform the first RA preamble / PRACH transmission at a second time interval T2, as shown in Figure 24. The wireless device may transmit / perform the first RA preamble / PRACH transmission via / through / on the candidate / target cell in one or more candidate / target cells. In the example of Figure 24, the wireless device can transmit / perform a first RA preamble / PRACH transmission via cell 1 / through cell 1 / on cell 1. A first control command (e.g., DCI, PDCCH command) can indicate the candidate / target cell (e.g., cell 1 in Figure 24) among the one or more candidate / target cells for the first RA preamble / PRACH transmission.

[0409] In the example of Figure 24, the base station (e.g., a base station serving a candidate / target cell, a candidate / target base station, etc.) may not receive the first RA preamble / PRACH transmission. For example, the base station may not receive the first RA preamble / PRACH transmission due to insufficient / low transmit power of the radio device used to perform / transmit the first RA preamble / PRACH transmission (e.g., unable to offset the effects of the communication channel / channel conditions). In response to the base station not receiving the first RA preamble / PRACH transmission, the source / serving base station (e.g., a base station serving a source / serving cell (e.g., cell 0 in Figure 24)) may transmit a second control command (e.g., DCI, PDCCH command).

[0410] A radio device (e.g., the UE in Figure 24) may receive a second control command (e.g., DCI, PDCCH command) during a third time interval (e.g., T3 as shown in Figure 24). The second control command (e.g., DCI, PDCCH command) may indicate a second procedure / process. The second control command (e.g., DCI, PDCCH command) may indicate the transmission (e.g., retransmission) of the second RA preamble / PRACH transmission. The second control command (e.g., DCI, PDCCH command) may indicate a candidate / target cell (e.g., cell 1) among the one or more candidate / target cells used for the second RA preamble / PRACH transmission.

[0411] In the example of Figure 24, the second process / procedure can be the same as the first process / procedure. For example, based on the fact that the second process / procedure is the same as the first process / procedure, the wireless device can increment a counter (e.g., a preamble transmission counter, a preamble power ramp counter). For example, the first control command (e.g., a DCI, PDCCH command) can include a first bit / field indicating the first process / procedure (e.g., a first RA / LTM / ETA process / procedure). The second control command (e.g., a DCI, PDCCH command) can include a second bit / field indicating the second process / procedure (e.g., a second RA / LTM / ETA process / procedure). The first bit / field can, for example, be the same as the second bit / field. For example, based on the fact that the first bit / field is the same as the second bit / field, the wireless device can increment a counter (e.g., a preamble transmission counter, a preamble power ramp counter). For example, the first bit / field may have been switched from the second bit / field (or not switched). The wireless device may increment a counter (e.g., a preamble transmission counter, a preamble power ramp counter) based, for example, on the fact that the second bit / field has not switched (or switched) from the first bit / field.

[0412] The second control command (e.g., DCI, PDCCH command) can instruct the transmission (e.g., initial transmission or retransmission) of the second RA preamble / PRACH transmission. The wireless device can transmit / perform the second RA preamble / PRACH transmission, for example, based on a counter (e.g., preamble transmission counter, preamble power ramp counter). For example, the wireless device can use the value of the counter (e.g., preamble transmission counter, preamble power ramp counter) in the first equation to determine the transmit / transmission power used for transmitting / performing the second RA preamble / PRACH transmission. The wireless device can, for example, perform / transmit the second RA preamble / PRACH transmission during a fourth time interval T4 (as shown in Figure 24).

[0413] In example embodiments, control commands (e.g., DCI, PDCCH commands) (e.g., the first DCI in Figure 23, the second DCI in Figure 23, the third DCI in Figure 23, the first DCI in Figure 24, the second DCI in Figure 24, etc.) can indicate the initial transmission or retransmission of the RA preamble / PRACH transmission, for example, based on fields indicating procedures / programs.

[0414] Figure 25A illustrates an example timing diagram of receiving a control command according to an embodiment of the present disclosure. A wireless device may receive a first control command (e.g., a DCI, PDCCH command) at a first time interval T1. The first control command (e.g., a DCI, PDCCH command) may indicate a first procedure (and / or include a first bit / field). The wireless device may receive a second control command (e.g., a DCI, PDCCH command) at, for example, a second time interval T2. T2 may, for example, follow T1. The second control command (e.g., a DCI, PDCCH command) may indicate a second procedure (and / or include a second bit / field). In the example of Figure 25A, the second procedure may be the same as the first procedure (e.g., based on the first bit / field being the same as the second bit / field). For example, based on the second procedure being the same as the first procedure (and / or the first bit / field being the same as the second bit / field), the second control command (e.g., a DCI, PDCCH command) may (implicitly) indicate a retransmission of the RA preamble / PRACH transmission. For example, based on the fact that the second process / procedure is the same as the first process / procedure (and / or the first bit / field is the same as the second bit / field), the wireless device can determine an incrementing counter (e.g., a preamble transmission counter, a preamble power ramp counter).

[0415] Figure 25B illustrates an example timing diagram of receiving a control command according to an embodiment of the present disclosure. A wireless device may receive a first control command (e.g., a DCI, PDCCH command) at a first time interval T1. The first control command (e.g., a DCI, PDCCH command) may indicate a first procedure (and / or include a first bit / field). The wireless device may receive a second control command (e.g., a DCI, PDCCH command) at, for example, a second time interval T2. T2 may, for example, follow T1. The second control command (e.g., a DCI, PDCCH command) may indicate a second procedure (and / or include a second bit / field). In the example of Figure 25B, the second procedure may differ from the first procedure (e.g., based on a difference between the first and second bits / fields). For example, based on a difference between the second and first procedures (and / or a difference between the first and second bits / fields), the second control command (e.g., a DCI, PDCCH command) may (implicitly) indicate the initial transmission of the RA preamble / PRACH. For example, based on the fact that the second process / procedure is different from the first process / procedure (and / or the first bit / field is different from the second bit / field), the wireless device can determine a non-incrementing (e.g., reset / initialize, maintain, etc.) counter (e.g., preamble transmission counter, preamble power ramp counter).

[0416] Figure 26 illustrates an example timing diagram according to an embodiment of the present disclosure. In the example of Figure 26, a radio device (e.g., the UE in Figure 26) receives a first control command (e.g., a DCI, PDCCH command). The radio device may receive the first control command (e.g., a DCI, PDCCH command) from a source / serving cell (e.g., cell 0 in Figure 26) / via the source / serving cell / through the source / serving cell / receive the first control command from the source / serving cell. The radio device may receive the first control command (e.g., a DCI, PDCCH command) from a source / serving base station (e.g., a base station serving the source / serving cell). The radio device may receive the first control command (e.g., a DCI, PDCCH command) during a first time interval (e.g., T1 as shown in Figure 26).

[0417] The first control command (e.g., DCI, PDCCH command) may indicate the transmission of the first RA preamble / PRACH. The first control command (e.g., DCI, PDCCH command) may indicate one or more candidate / target cells (e.g., cell 1 in FIG. 26) for the first RA preamble / PRACH transmission. The radio device may receive one or more messages (e.g., similar / identical to one or more messages in the example embodiments of FIG. 17, FIG. 18, FIG. 22, FIG. 23 and / or FIG. 24). The one or more messages may include one or more candidate / target (LTM cell) configurations (e.g., one or more candidate / target (LTM cell) configuration parameters). The one or more candidate / target (LTM cell) configurations may be used for one or more candidate / target cells (e.g., for LTM procedures / processes). Each candidate / target (LTM cell) configuration in the one or more candidate / target (LTM cell) configurations may be used for / associated with a corresponding candidate / target cell in the one or more candidate / target cells.

[0418] The wireless device may, for example, transmit / perform a first RA preamble / PRACH transmission in response to receiving a first control command (e.g., DCI, PDCCH command). The wireless device may, for example, transmit / perform the first RA preamble / PRACH transmission via / through a candidate / target cell among the one or more candidate / target cells (e.g., based on receiving a first control command (e.g., DCI, PDCCH command) indicating a candidate / target cell among the one or more candidate / target cells).

[0419] The wireless device may, for example, transmit / execute a first RA preamble / PRACH transmission during a second time interval (e.g., T2 in Figure 26). The wireless device may transmit / execute, for example, a first RA preamble / PRACH transmission for a first RA procedure / process, a first RA preamble / PRACH transmission for a first RA procedure / process, a first RA preamble / PRACH transmission transmitted / executed via a first RA procedure / process, or a first RA preamble / PRACH transmission transmitted / executed as part of a first RA procedure / process.

[0420] In the example, the wireless device can execute a second RA procedure / process. The second RA procedure / process can be used for beam failure recovery, consistent LBT failure recovery, RRC connection re-establishment, downlink data arrival, uplink data arrival, scheduling request failure, time alignment establishment for assisted timing advance / alignment groups, requests for other system information, ETA / LTM, etc. The second RA procedure / process can be used, for example, for the source / serving cell / via the source / serving cell / belonging to the source / serving cell / associated with the source / serving cell. The second RA procedure / process can be used, for example, for the second candidate / target cell (e.g., cell 2 in Figure 17) among the one or more candidate / target cells / via the second candidate / target cell / belonging to the second candidate / target cell / associated with the second candidate / target cell. The second candidate / target cell among the one or more candidate / target cells can be different from the candidate / target cells among the one or more candidate / target cells. The source / serving cell can be different from the candidate / target cell. The source / serving cell can be different from the second candidate / target cell.

[0421] At the end of the second RA process / program / after the end / before and after the end, the value of the counter (e.g., preamble transmission counter, preamble power ramp counter) can be N (as shown in Figure 26). N can be, for example, 1, 2, 3, ..., 10, ... etc.

[0422] In the example of Figure 26, the wireless device receives a second control command (e.g., DCI, PDCCH command). The wireless device may receive the second control command (e.g., DCI, PDCCH command) at, for example, a third time interval (e.g., T3 in Figure 26). The third time interval may be after the second time interval. The third time interval may be, for example, after the end of the second RA process / procedure. The second RA process / procedure may occur, for example, between the second time interval and the third time interval.

[0423] In the example of Figure 26, the second control command (e.g., DCI, PDCCH command) can instruct the retransmission of the second RA preamble / PRACH transmission. The second control command (e.g., DCI, PDCCH command) can indicate the candidate / target cell among the one or more candidate / target cells used for the second RA preamble / PRACH transmission.

[0424] In existing implementations, the wireless device can increment a preamble power ramp counter in response to receiving a second control command (e.g., DCI, PDCCH command) indicative of a retransmission of the second RA preamble / PRACH. For example, the wireless device can increment the preamble power ramp counter from N to N+1. After incrementing the preamble power ramp counter, the wireless device can determine the transmission power based on N+1. As shown in Figure 26, the wireless device can use the transmission power to transmit the second RA preamble / PRACH in a fourth time interval T4.

[0425] Existing implementations may cause wireless devices to use more power than necessary. This can lead to increased power consumption, reduced battery life, and / or increased interference in the network.

[0426] Embodiments of this disclosure relate to a method for incrementing a counter (e.g., a preamble transmission counter, a preamble power ramp counter) when a control command (e.g., a DCI, PDCCH command) instructs a retransmission of a RA preamble / PRACH transmission (e.g., for LTM / ETA). According to an example embodiment, the wireless device may use at least two counters (e.g., at least two preamble transmission counters, at least two preamble power ramp counters). The at least two counters (e.g., at least two preamble transmission counters, at least two preamble power ramp counters) may include a first counter (e.g., a first preamble transmission counter, a first preamble power ramp counter) and a second counter (e.g., a second preamble transmission counter, a second preamble power ramp counter). In response to receiving a first control command (e.g., DCI, PDCCH command), which indicates a retransmission via a first cell (e.g., source / serving cell) / the first cell's / through the first cell / on the first cell / associated with the first cell's first RA preamble / PRACH transmission, the radio device may increment a first counter (e.g., a first preamble transmission counter, a first preamble power ramp counter). For example, the first counter (e.g., the first preamble transmission counter, the first preamble power ramp counter) may be associated with the first cell (e.g., the source / serving cell).

[0427] In response to receiving a second control command (e.g., DCI, PDCCH command) indicating a retransmission via a second cell (e.g., candidate / target cell) / the second cell / through the second cell / on the second cell / associated with the second cell's second RA preamble / PRACH), the radio device may increment a second counter (e.g., a second preamble transmission counter, a second preamble power ramp counter). For example, the second counter (e.g., the second preamble transmission counter, the second preamble power ramp counter) may be associated with the second cell (e.g., candidate / target cell). For example, the second counter (e.g., the second preamble transmission counter, the second preamble power ramp counter) may be associated with an LTM / ETA procedure / routine.

[0428] Example embodiments may provide enhancements to counters (e.g., preamble transmission counters, preamble power ramp counters) for incrementing in response to receiving a control command (e.g., DCI, PDCCH command) indicative of a retransmission of RA preamble / PRACH. Example embodiments may provide enhancements to determine the transmit / transfer power used for transmitting / performing RA preamble / PRACH transmissions (e.g., for LTM / ETA procedures). By using example embodiments of this disclosure, wireless devices can avoid using higher / more / greater transmit / transfer power for RA preamble / PRACH transmissions than required. This can reduce power consumption in the wireless device, increase battery life, and / or reduce latency in the network.

[0429] Figure 27 illustrates an example timing diagram according to an aspect of an embodiment of the present disclosure. According to the example of Figure 27, a wireless device may receive one or more messages. The wireless device may receive the one or more messages from a base station (e.g., a serving base station, a base station serving a source / serving cell, such as cell 0 in Figure 27). The one or more messages may include one or more candidate / target (LTM cell) configurations (e.g., for LTM). The one or more candidate / target (LTM cell) configurations (e.g., one or more candidate / target (LTM cell) configuration parameters) may be used / associated with one or more candidate / target cells (e.g., for LTM procedures / programs). Each candidate / target (LTM cell) configuration in the one or more candidate / target (LTM cell) configurations may be used / associated with a corresponding candidate / target cell among the one or more candidate / target cells. The one or more candidate / target cells may include a candidate / target cell (e.g., cell 1 in Figure 27).

[0430] In the example of Figure 27, the radio device (e.g., the UE in Figure 27) receives a first control command (e.g., a DCI or PDCCH command). The radio device may receive the first control command (e.g., the DCI or PDCCH command) at a first time (e.g., T1 in Figure 27). The first control command (e.g., the DCI or PDCCH command) may indicate the transmission of a first RA preamble / PRACH transmission (e.g., initial transmission or retransmission). The first control command (e.g., the DCI or PDCCH command) may indicate the transmission, for example, via a first RA preamble / PRACH transmission of a candidate / target cell among the one or more candidate / target cells.

[0431] In the example, a control command (e.g., DCI, PDCCH command) can instruct a retransmission of the first RA preamble / PRACH transmission. In response to the control command (e.g., DCI, PDCCH command) instructing a retransmission of the first RA preamble / PRACH transmission, the radio device can increment a first counter (e.g., a first preamble transmission counter, a first preamble power ramp counter). For example, in response to a control command (e.g., DCI, PDCCH command) instructing a retransmission of the first RA preamble / PRACH transmission via a candidate / target cell (e.g., cell 1 in FIG. 27) / on the candidate / target cell / through the candidate / target cell / to the candidate / target cell / toward the candidate / target cell / for the candidate / target cell), the radio device can increment a first counter (e.g., a first preamble transmission counter, a first preamble power ramp counter). The first counter (e.g., a first preamble transmission counter, a first preamble power ramp counter) can be associated with, for example, the candidate / target cell. The first counter (e.g., the first preamble transmission counter, the first preamble power ramp counter) can be associated with, for example, an LTM / ETA program.

[0432] The wireless device may, for example, transmit / perform a first RA preamble / PRACH transmission at a second time (e.g., T2 in Figure 27). The wireless device may utilize / use a first transmit / transmit power to transmit / perform the first RA preamble / PRACH transmission. The wireless device may determine the first transmit / transmit power based on a first counter (e.g., a first preamble transmission counter, a first preamble power ramp counter). For example, the wireless device may use the value of the first counter (e.g., a first preamble transmission counter, a first preamble power ramp counter) in a first equation to determine the first transmit / transmit power. The wireless device may transmit / perform the first RA preamble / PRACH transmission, for example, as part of / for the first RA / LTM / ETA process / procedure.

[0433] In the example of Figure 27, the wireless device can execute a second RA / LTM / ETA procedure / process. The second RA / LTM / ETA procedure / process may include, for example, the wireless device transmitting one or more RA preamble / PRACH transmissions via a second cell. In this example, the second cell may be a source / serving cell (e.g., cell 0 in Figure 27). In another example (not shown in Figure 27), the second cell may be the second candidate / target cell among the one or more candidate / target cells. The wireless device may use a second counter (e.g., a second preamble transmission counter, a second preamble power ramp counter) for the second RA / LTM / ETA procedure / process. For example, based on the second RA / LTM / ETA procedure / process being associated with / used in a cell different from the first RA / LTM / ETA procedure / process (e.g., cell 0, the second candidate / target cell among the one or more candidate / target cells) (e.g., the first RA / LTM / ETA procedure / process being associated with / used in the candidate / target cell among the one or more candidate / target cells), the wireless device may use a second counter (e.g., a second preamble transmission counter, a second preamble power ramp counter). For example, a second counter (e.g., a second preamble transmission counter, a second preamble power ramp counter) may be associated with a second candidate / target cell (and / or source / serving cell). For example, a second counter (e.g., a second preamble transmission counter, a second preamble power ramp counter) may be associated with a non-LTM / ETA RA procedure.

[0434] For example, a first counter (e.g., a first preamble transmission counter, a first preamble power ramp counter) may be associated with / used in an LTM / ETA procedure. A second counter (e.g., a second preamble transmission counter, a second preamble power ramp counter) may be associated with / used in a non-LTM / ETA procedure (e.g., a RA procedure with the source / serving cell, a RA procedure for BFR, a RA procedure for LBT, a RA procedure for initial access, a RA procedure for handover, a RA procedure for small data transfer, a RA procedure for other SI requests, etc.). Based on the first RA / LTM / ETA procedure / process being associated with / used in an LTM / ETA procedure, the radio device may use the first counter (e.g., a first preamble transmission counter, a first preamble power ramp counter) in the first RA / LTM / ETA procedure / process. For example, based on the second RA procedure / process not being associated with an LTM / ETA procedure, the radio device may use the second counter (e.g., a second preamble transmission counter, a second preamble power ramp counter) in the second RA procedure / process.

[0435] In the example of Figure 27, the radio device receives a second control command (e.g., DCI, PDCCH command). The radio device may receive the second control command (e.g., DCI, PDCCH command) via, for example, a source / serving cell (e.g., cell 0 in Figure 27) / from, or on the source / serving cell. The radio device may receive the second control command (e.g., DCI, PDCCH command) at a third time interval (e.g., T3 in Figure 27). The second control command (e.g., DCI, PDCCH command) may instruct, for example, a retransmission of a second RA preamble / PRACH transmission (e.g., for LTM / ETA procedures / processes). The second control command (e.g., DCI, PDCCH command) may instruct, for example, a retransmission of a second RA preamble / PRACH transmission for / to / via, one or more candidate / target cells. In response to receiving a second control command (e.g., DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH (e.g., for LTM / ETA procedures / processes), the radio device may, for example, increment a first counter (e.g., a first preamble transmission counter, a first preamble power ramp counter) based on the second control command (e.g., DCI, PDCCH command) associated with / for / indicating a candidate / target cell among the one or more candidate / target cells for the second RA preamble / PRACH transmission (e.g., for LTM / ETA procedures / processes).

[0436] In the example, T3 can be performed after the second RA procedure (completed) (as shown in Figure 27).

[0437] In the example, the wireless device may transmit / perform a second RA preamble / PRACH transmission, for example, during a fourth time interval (e.g., T4 as shown in Figure 27). The wireless device may transmit / perform the second RA preamble / PRACH transmission, for example, based on a first counter (e.g., a first preamble transmission counter, a first preamble power ramp counter). For instance, the wireless device may use / utilize a second transmit / transmit power to transmit / perform the second RA preamble / PRACH transmission. For example, by using the value of the first counter in the first equation, the wireless device may determine the second transmit / transmit power based on the value of the first counter (e.g., the first preamble transmission counter, the first preamble power ramp counter).

[0438] By using different counters (e.g., preamble transmission counter, preamble power ramp counter) for the RA / LTM / ETA process / procedure via one or more candidate / target cells and for the RA procedure via the serving / source cell, the wireless device can avoid unnecessarily incrementing the counters (e.g., preamble transmission counter, preamble power ramp counter) across different RA / ETA / LTM procedures / procedures. An example of incrementing counters (e.g., preamble transmission counter, preamble power ramp counter) across different RA / ETA / LTM procedures / procedures (e.g., performed by the wireless device based on prior art) is shown in Figure 26 (e.g., at T3). This could cause the wireless device to use unnecessarily high (e.g., exceeding required, exceeding necessary, causing interference, etc.) transmit / transmit power to transmit / perform RA preamble / PRACH transmissions.

[0439] In the example, after the fourth time interval (e.g., T4 in Figure 27), the wireless device may receive a third control command (e.g., DCI, PDCCH command).

[0440] In the example, a third control command (e.g., DCI, PDCCH command) can instruct a retransmission of a third RA preamble / PRACH transmission. The third control command (e.g., DCI, PDCCH command) can instruct, for example, a retransmission of a third RA preamble / PRACH transmission via / associated with a second candidate / target cell among the one or more candidate / target cells. The second candidate / target cell among the one or more candidate / target cells may be different from (e.g., not identical to) the source / serving cell (e.g., cell 0 in FIG. 27). The second candidate / target cell among the one or more candidate / target cells may be different from (e.g., not identical to) the candidate / target cell among the one or more candidate / target cells (e.g., cell 1 in FIG. 27).

[0441] In the example, in response to receiving a control command (e.g., DCI, PDCCH command) indicating a retransmission via / for / towards / associated with the third RA preamble / PRACH of the second candidate / target cell, the radio device may not increment (e.g., may initialize, may reset (e.g., reset to 1 or 0), may maintain, etc.) a first counter (e.g., a first preamble transmission counter, a first preamble power ramp counter). In response to receiving a control command (e.g., DCI, PDCCH command) indicating a retransmission via / for / towards / associated with the third RA preamble / PRACH of the second candidate / target cell, the radio device may initialize / reset (e.g., reset to 0, 1, etc.) a third counter (e.g., a third preamble transmission counter, a third preamble power ramp counter). The third counter (e.g., a third preamble transmission counter, a third preamble power ramp counter) may be associated with / used for (ETA / LTM procedures / programs) the second candidate / target cell.

[0442] If the RA procedure is initiated / triggered / indicated as an RA preamble / PRACH retransmission by a control command (e.g., DCI, PDCCH command) for a candidate / target cell (e.g., for LTM), the radio device may increment a counter (e.g., preamble transmission counter, preamble power ramp counter) in response, for example, to a first procedure (e.g., LTM, ETA, RA procedure, etc.) indicated by the control command (e.g., DCI, PDCCH command) that is the same as a second / previous procedure (e.g., LTM, ETA, RA procedure, etc.) indicated by a previous / second control command (e.g., DCI, PDCCH command) in the previous / second control command.

[0443] Figure 28 illustrates an example flowchart of one aspect of an embodiment according to the present disclosure. In the example of Figure 28, the wireless device may execute a first RA / ETA / LTM procedure / process. In the example, the wireless device may receive a first control command (e.g., DCI, PDCCH command) indicating a transmission (e.g., initial transmission or retransmission) for a first RA preamble / PRACH transmission for the first RA / ETA / LTM procedure / process. The first control command (e.g., DCI, PDCCH command) may indicate a first identity for the first RA / ETA / LTM procedure / process. In the example, the wireless device may not receive the first control command (e.g., DCI, PDCCH command) for the first RA / ETA / LTM procedure / process. For example, the wireless device may initiate the first RA / ETA / LTM procedure / process (e.g., for BFR, consistent LBT failure recovery, etc.). Based on the fact that the wireless device has not received the first control command (e.g., DCI, PDCCH command) for the first RA / ETA / LTM procedure / process, the first RA / ETA / LTM procedure / process may not be associated with an identity.

[0444] Following the first RA / ETA / LTM procedure / process, the wireless device may receive a second control command (e.g., DCI, PDCCH command). The second control command (e.g., DCI, PDCCH command) may instruct a retransmission of the second RA preamble / PRACH transmission. In one example, the second RA preamble / PRACH transmission may be the same as the first RA preamble / PRACH transmission. In another example, the second RA preamble / PRACH transmission may be different from the first RA preamble / PRACH transmission (e.g., not identical). The second control command (e.g., DCI, PDCCH command) may include a second field. The second field may indicate, for example, a second identity for the second RA / ETA / LTM procedure / process, or a second identity associated with the second RA / ETA / LTM procedure / process.

[0445] In the example, the second identity can be the same as the first identity (e.g., the second RA / ETA / LTM procedure / process can be the same as the first RA / ETA / LTM procedure / process (e.g., a continuation thereof)). In the example, the first control command (e.g., DCI, PDCCH command) can indicate the first candidate / target cell (e.g., for LTM / ETA). The second control command (e.g., DCI, PDCCH command) can indicate the second candidate / target cell (e.g., for LTM / ETA). The first candidate / target cell can be the same as the second candidate / target cell. In response to receiving a second control command (e.g., DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH, the radio device can increment a counter (e.g., a preamble transmission counter, a preamble power ramp counter) for example, based on the fact that the second identity can be the same as the first identity (and / or based on the fact that the first candidate / target cell is the same as the second candidate / target cell).

[0446] In the example, the second identity may be different from the first identity (or the first RA / ETA / LTM procedure / process may not be associated with an identity). The second candidate / target cell may, for example, be different from the first candidate / target cell. In response to receiving a second control command (e.g., DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH, the radio device may, for example, not increment a counter (e.g., preamble transmission counter, preamble power ramp counter) based on the fact that the second identity is different from the first identity. In response to receiving a second control command (e.g., DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH, the radio device may, for example, not increment a counter (e.g., preamble transmission counter, preamble power ramp counter) based on the fact that the first RA / ETA / LTM procedure / process is not associated with an identity. In response to receiving a second control command (e.g., DCI, PDCCH command) indicating a retransmission of the second RA preamble / PRACH, the radio device may, for example, not increment a counter (e.g., preamble transmission counter, preamble power ramp counter) based on the difference between the first candidate / target cell and the second candidate / target cell.

[0447] Figure 29 illustrates an example flowchart of an embodiment according to the present disclosure. In the example of Figure 29, the wireless device may receive control commands (e.g., DCI, PDCCH commands). The control commands (e.g., DCI, PDCCH commands) may instruct the retransmission of RA preamble / PRACH transmission (e.g., via one or more candidate / target cells / on one or more candidate / target cells). In response to receiving the control command (e.g., DCI, PDCCH command) instructing the retransmission of RA preamble / PRACH transmission, the wireless device may determine the value of a counter (e.g., preamble transmission counter, preamble power ramp counter) based, for example, on the current value of a counter (e.g., preamble transmission counter, preamble power ramp counter).

[0448] In the example, the (current) value of a counter (e.g., preamble transmission counter, preamble power ramp counter) can be a maximum value (e.g., preambleTransMax, the maximum value of the preamble power ramp counter, etc.). In response to receiving a control command (e.g., DCI, PDCCH command) indicating a retransmission of RA preamble / PRACH, the wireless device may not increment the counter (e.g., it may maintain, may remain the same, may be reset (e.g., reset to 0 or 1), may be initialized, etc.) based on the fact that the (current) value of the counter (e.g., preamble transmission counter, preamble power ramp counter) is a maximum value (e.g., preambleTransMax, the maximum value of the preamble power ramp counter, etc.).

[0449] In the example, the (current) value of a counter (e.g., preamble transmission counter, preamble power ramp counter) can be less than (e.g., below, less than, below, etc.) the maximum value (e.g., preambleTransMax, the maximum value of the preamble power ramp counter, etc.). In response to receiving a control command (e.g., DCI, PDCCH command) indicating a retransmission of RA preamble / PRACH, the wireless device can increment (e.g., increment by 1) the counter (e.g., preamble transmission counter, preamble power ramp counter), for example, based on the fact that the (current) value of the counter (e.g., preamble transmission counter, preamble power ramp counter) is less than the maximum value (e.g., preambleTransMax, the maximum value of the preamble power ramp counter, etc.).

[0450] An example method includes: receiving one or more Radio Resource Control (RRC) messages by a wireless device, the RRC messages including configuration parameters for one or more candidate target cells for a mobility (LTM) procedure triggered at Layer 1 and Layer 2; receiving control commands (e.g., DCI, PDCCH commands) indicating: retransmission of an RA preamble via one or more candidate / target cells; and a field indicating the identity of the RA procedure; determining a value for a power ramp counter based on: the control command (e.g., DCI, PDCCH command) indicating the retransmission of the RA preamble; and the field; and transmitting the RA preamble at a transmission power determined based on the power ramp counter.

[0451] The example method described above, wherein the field indicates whether the RA process is a new RA process.

[0452] One or more of the above example methods, wherein the field indicates whether the RA process is the same as the previous RA process.

[0453] One or more of the above example methods, wherein the field is switched based on the bit fields included in the field to indicate whether the RA process is the same as the previous RA process.

[0454] In some embodiments, control commands (e.g., DCI, PDCCH commands) may indicate a transmission (e.g., initial transmission or retransmission) for / via / to / towards / with the cell / RA preamble / PRACH transmission associated with the cell, based on a field (e.g., cell indicator) indicating the cell (e.g., serving / source cell, candidate / target cell, etc.). The cell indicator field may indicate the cell used for the corresponding RA preamble / PRACH transmission.

[0455] In some embodiments, control commands (e.g., DCI, PDCCH commands) can instruct transmissions (e.g., initial transmissions or retransmissions) for a cell (e.g., serving / source cell, candidate / target cell, etc.) / via the cell / to the cell / towards the cell / with the associated RA preamble / PRACH transmission, based on the cell on which the radio device receives the control commands (e.g., DCI, PDCCH commands) on / via the source / serving cell. For example, the radio device can receive control commands (e.g., DCI, PDCCH commands) via the source / serving cell / on the source / serving cell. Control commands (e.g., DCI, PDCCH commands) can instruct transmissions on / via the source / serving cell / towards the source / serving cell / with the associated RA preamble / PRACH transmission, based on the radio device receiving control commands (e.g., DCI, PDCCH commands) via the source / serving cell / on the source / serving cell.

[0456] Figure 30 illustrates an example timing diagram according to one aspect of an embodiment of the present disclosure. According to the example of Figure 30, a radio device (e.g., the UE in Figure 30) may execute a first RA procedure (e.g., for beam fault recovery, for initial access, for TA acquisition (e.g., LTM TA acquisition), etc.). In the example, the radio device's MAC / higher layer / entity may initiate the first RA procedure. The radio device may transmit / execute a first RA preamble / PRACH transmission for the first RA procedure. The radio device may use a first subcarrier spacing (SCS) to transmit / execute the first RA preamble / PRACH transmission.

[0457] The wireless device can receive control commands (e.g., DCI, PDCCH commands) that trigger a second RA procedure (indicating the transmission of a second RA preamble / PRACH). In the example of Figure 30, the wireless device can receive control commands (e.g., DCI, PDCCH commands) after transmitting / performing a first RA preamble / PRACH transmission (e.g., the preamble in Figure 30). The wireless device can receive control commands (e.g., DCI, PDCCH commands) via / from a source / serving cell (e.g., cell 0 in Figure 17).

[0458] The second RA procedure (e.g., second RA preamble / PRACH transmission) can be used / towards / via / associated with one or more candidate / target cells (e.g., cell 1 in Figure 17). The second RA procedure can be used / associated with LTM. The second RA procedure can be used for ETA / is the RA procedure of ETA / associated with ETA. In response to receiving a control command (e.g., DCI, PDCCH command) that triggers / instructs the second RA procedure / second RA preamble / PRACH transmission, the radio device can transmit / perform the second RA preamble / PRACH transmission for the second RA procedure.

[0459] In existing implementations, a wireless device may use the same SCS (e.g., the first SCS) for both a second RA procedure (e.g., for transmitting the second RA preamble) and a first RA procedure (e.g., initiated by the wireless device's MAC / higher layer / entity). In response to a control command (e.g., DCI, PDCCH command) to initiate / trigger the second RA procedure, such as based on using the first SCS for a first RA procedure initiated / triggered by a higher / MAC layer / entity of the wireless device, the wireless device may use the same SCS (e.g., the first SCS) as the SCS used for the first RA procedure (e.g., for transmitting the first RA preamble) for the second RA procedure (e.g., for transmitting the second RA preamble). The wireless device may use the same SCS for both the second RA procedure (e.g., for transmitting the second RA preamble) and the first RA procedure (e.g., for transmitting the first RA preamble), for example, to reduce signaling overhead in the control commands (e.g., DCI, PDCCH commands) (e.g., if the control command instructs the SCS (e.g., the first SCS) to be used for transmitting the second RA preamble, the signaling overhead will increase).

[0460] Prior art implementations can cause a wireless device to use a first SCS to transmit / perform a second RA preamble / PRACH transmission. The wireless device can transmit / perform the second RA preamble / PRACH transmission via / to / toward, for example, a candidate / target (LTM) cell (e.g., cell 1 in Figure 30). The wireless device can also transmit / perform the first RA preamble / PRACH transmission via / to / toward, for example, a source / serving cell (e.g., cell 0 in Figure 30). The candidate / target cell can be different from the source / serving cell. The candidate / target cell (e.g., cell 1 in Figure 30) and the source / serving cell (e.g., cell 0 in Figure 30) can operate using different fundamental parameters (e.g., different SCSs in the 5G / NR spectrum). Using the same SCS for the first RA preamble / PRACH transmission for / to / via the source / serving cell and for the second RA preamble / PRACH transmission for / to / via the candidate / target cell may result in interference, underutilization / waste of resources (e.g., due to retransmissions), signaling overhead (e.g., for requesting and / or performing retransmissions), increased power consumption (e.g., due to performing retransmissions), and / or reduced battery life (e.g., due to increased power consumption).

[0461] Embodiments of this disclosure relate to a method for determining an SCS for transmitting RA preamble / PRACH transmission, for example via a candidate / target cell (e.g., for LTM / ETA) / through the candidate / target cell / on the candidate / target cell, for example, an RA procedure triggered by a control command (e.g., DCI, PDCCH command).

[0462] In an example embodiment, the wireless device may use / utilize a first SCS to perform / transmit a first RA preamble / PRACH transmission. The wireless device may, for example, transmit / perform a first RA preamble / PRACH transmission for a first RA procedure (e.g., for BFR, consistent LBT fault recovery, other SI requests, etc.) initiated / triggered by a higher / MAC layer / entity of the wireless device via / on the serving / source cell. The wireless device may receive control commands (e.g., DCI, PDCCH commands) indicating, for example, a second RA preamble / PRACH transmission for a second RA procedure. The wireless device may determine a second SCS for transmitting / performing the second RA preamble / PRACH transmission based on the control commands (e.g., DCI, PDCCH commands). In the example, the control commands (e.g., DCI, PDCCH commands) may indicate a transmission destined for / via / for a second RA preamble / PRACH transmission targeting the serving / source cell. The radio device can determine that the second SCS is the same as the first SCS based on control commands (e.g., DCI, PDCCH commands) indicating a transmiss...

Claims

1. A method comprising: The wireless device receives a first Physical Downlink Control Channel (PDCCH) command, which initiates a first Random Access RA procedure for a candidate cell for a Layer 1 or Layer 2 triggered Mobility LTM procedure; initializes a power ramp counter to a first value based on the first PDCCH command indicating initial preamble transmission; completes the first RA procedure after transmitting the first RA preamble via the candidate cell using a first transmission power determined based on the first value for the first RA procedure; receives a second PDCCH command to initiate a second RA procedure for the candidate cell; increments the power ramp counter from the first value to a second value in response to the second PDCCH command indicating preamble retransmission; and transmits a second RA preamble via the candidate cell using a second transmission power determined based on the second value for the second RA procedure.

2. A method comprising: The wireless device completes a first RA procedure by transmitting a first random access RA preamble using a first transmission power determined based on a first value of a power ramp counter; receives a command to initiate a second RA procedure; in response to the command instructing the preamble to be retransmitted, increments the power ramp counter from the first value to a second value; and transmits a second RA preamble for the second RA procedure using a second transmission power determined based on the second value.

3. The method according to claim 2, wherein the command is a Physical Downlink Control Channel (PDCCH) command.

4. The method according to claim 2 or 3, further comprising receiving a first PDCCH command, the first PDCCH command initiating the first RA procedure of a candidate cell for a mobility LTM procedure triggered at layer 1 or layer 2.

5. The method according to claim 4 further includes initializing the power ramp counter to the first value based on the first PDCCH command indicating the initial preamble transmission.

6. The method of claim 4 or 5, wherein the transmission of the first RA preamble is performed via the candidate cell.

7. The method according to any one of claims 4 to 6, wherein the transmission of the second RA preamble is performed via the candidate cell.

8. The method according to any one of claims 2 to 7, wherein the transmission of the first RA preamble is for the first RA procedure.

9. The method according to any one of claims 2 to 8, further comprising receiving one or more LTM configurations of one or more candidate cells for LTM procedures.

10. The method of claim 9, wherein the one or more candidate cells include the candidate cells.

11. The method of claim 9 or 10, wherein each LTM configuration in the one or more LTM configurations is the LTM configuration of a corresponding candidate cell in the one or more candidate cells.

12. The method according to any one of claims 4 to 11, wherein the first downlink control information includes the first PDCCH command.

13. The method according to any one of claims 2 to 12, wherein the second downlink control information includes the command.

14. The method according to any one of claims 5 to 13, wherein the first PDCCH command includes a first field indicating the initial preamble transmission.

15. The method according to any one of claims 2 to 14, wherein the command includes a second field indicating preamble retransmission.

16. The method according to any one of claims 2 to 15, wherein the first RA preamble and the second RA preamble are different from each other.

17. The method according to any one of claims 2 to 16, wherein the first RA preamble index based on the first RA preamble is different from the second RA preamble index of the second RA preamble, and the first RA preamble and the second RA preamble are different from each other.

18. The method according to any one of claims 2 to 17, wherein the second RA procedure is different from the first RA procedure.

19. The method according to any one of claims 2 to 18, wherein the first value is equal to one.

20. The method according to any one of claims 2 to 19, wherein the first value is not equal to one.

21. The method according to any one of claims 2 to 20, wherein the first value is equal to zero.

22. The method according to any one of claims 2 to 21, wherein incrementing the power ramp counter comprises incrementing the power ramp counter by one from the first value.

23. The method according to any one of claims 2 to 22, wherein the second value is two.

24. A method comprising: A radio device receives a Radio Resource Control (RRC) message, the RRC message including one or more configuration parameters for a candidate cell for a mobility LTM procedure triggered at Layer 1 or Layer 2, wherein the one or more configuration parameters include: one or more Random Access Channel (RACH) configuration parameters for the candidate cell; and a first subcarrier spacing transmitted via the random access RA preamble of the candidate cell; in response to receiving a PDCCH command to initiate an RA procedure for early uplink synchronization with the candidate cell, the RA preamble is transmitted via the candidate cell and for the RA procedure using the first subcarrier spacing.

25. The method of claim 24, wherein the downlink control information includes the PDCCH command.

26. The method of claim 24 or 25, wherein the one or more RACH configuration parameters include one or more RA resources.

27. The method according to any one of claims 24 to 26, wherein the RRC message includes one or more second configuration parameters.

28. The method of claim 27, wherein the one or more second configuration parameters are configuration parameters for one or more candidate cells for the LTM procedure.

29. The method of claim 27 or 28, wherein the one or more second configuration parameters include the one or more configuration parameters.

30. The method according to any one of claims 27 to 29, wherein the one or more candidate cells include the candidate cells.

31. The method according to any one of claims 24 to 30, further comprising receiving a second PDCCH command.

32. The method of claim 31, wherein the second PDCCH command initiates the second RA procedure.

33. The method of claim 32, wherein the second RA procedure is used for the second cell.

34. The method of claim 33, wherein the second cell is different from the candidate cell.

35. The method of claim 33 or 34, wherein receiving the PDCCH command is performed via the second cell.

36. The method according to any one of claims 33 to 35, wherein receiving the second PDCCH command is performed via the second cell.

37. The method according to any one of claims 33 to 36, wherein the second PDCCH command indicates a second RA preamble.

38. The method of claim 37, further comprising, in response to receiving the second PDCCH command, transmitting the second RA preamble via the second cell using the second subcarrier spacing.

39. The method of claim 38, wherein the second subcarrier spacing is different from the first subcarrier spacing.

40. A method comprising: The radio device receives one or more messages, the one or more messages including configuration parameters for one or more candidate cells for a mobility LTM procedure triggered at Layer 1 or Layer 2; receives downlink control information (DCI), the DCI including a field indicating retransmission of a first random access (RA) preamble via one or more candidate cells; in response to the DCI including the field indicating the retransmission of the first RA preamble via the candidate cells, determines whether to increment a power ramp counter based on whether a listen-before-talk (LBT) failure occurs during transmission of a second RA preamble via the candidate cells; and transmits the first RA preamble via the candidate cells at a transmission power determined based on the power ramp counter.

41. The method of claim 40, wherein the one or more messages are one or more Radio Resource Control (RRC) reconfiguration messages.

42. The method of claim 40 or 41, wherein the configuration parameters include one or more configurations for the one or more candidate cells.

43. The method of claim 42, wherein each of the one or more configurations is for a corresponding candidate cell among the one or more candidate cells.

44. The method according to any one of claims 40 to 43, wherein the DCI is a physical downlink control channel command.

45. The method according to any one of claims 40 to 44, wherein the DCI is DCI format 1_0.

46. ​​The method of any one of claims 40 to 45, wherein the determination includes the Media Access Control (MAC) entity of the wireless device determining whether to increment the power ramp counter.

47. The method according to any one of claims 40 to 46, wherein the wireless device transmits the first RA preamble in the absence of LBT failure.

48. A method comprising: The wireless device receives the first physical downlink control channel (PDCCH) command that initiates the first random access (RA) procedure for the first cell. Based on the first PDCCH command indicating preamble retransmission for the first RA preamble of the first cell, increment a first power ramp counter; transmit the first RA preamble via the first cell and for the first RA procedure using a first transmission power determined based on the first power ramp counter; receive a second PDCCH command indicating a second random access procedure for the second cell; based on the second PDCCH command indicating preamble retransmission for the second RA preamble of the second cell, increment a second power ramp counter; and transmit the second RA preamble via the second cell and for the second RA procedure using a second transmission power determined based on the second power ramp counter.

49. An apparatus comprising one or more processors and a memory, the memory storing instructions that, when executed by the one or more processors, cause the apparatus to perform at least the method according to any one of claims 1 to 48.

50. A non-transitory computer-readable medium comprising instructions that, when executed by one or more processors of the device, cause the device to perform the method according to any one of claims 1 to 48.

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