Uplink Synchronization for Mobility

Abstract

A method can include receiving, by a wireless device, a layer 1 or 2 triggered mobility (LTM) timing advance command (TAC) medium access control (MAC) control element (CE) including a TAC indicating a first timing advance (TA) value of a candidate cell of candidate cells of a conditional LTM procedure. The method can also include determining one or more conditions to switch to the candidate cell to be satisfied. The method can further include, in response to the determining, performing a random access (RA) channel (RACH)-less conditional LTM cell switch based on successfully measuring a second TA value for the candidate cell. The RACH-less conditional LTM cell switch includes transmitting, via the candidate cell, a physical uplink shared channel (PUSCH) transmission using the second TA value.

Description

Docket No.: 24-1257PCTTITLEUplink Synchronization for MobilityCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 715,235, filed November 1 , 2024, which is hereby incorporated by reference in its entirety.BRIEF DESCRIPTION OF THE DRAWINGS

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

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

[0004] FIG. 2A and FIG. 2B respectively illustrate a New Radio (NR) user plane and control plane protocol stack.

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

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

[0007] FIG. 4B illustrates an example format of a MAC subheader in a MAC PDU.

[0008] FIG. 5A and FIG. 5B respectively illustrate a mapping between logical channels, transport channels, and physical channels for the downlink and uplink.

[0009] FIG. 6 is an example diagram showing RRC state transitions of a UE.

[0010] FIG. 7 illustrates an example configuration of an NR frame into which OFDM symbols are grouped.

[0011] FIG. 8 illustrates an example configuration of a slot in the time and frequency domain for an NR carrier.

[0012] FIG. 9 illustrates an example of bandwidth adaptation using three configured BWPs for an NR carrier.

[0013] FIG. 10A illustrates three carrier aggregation configurations with two component carriers.

[0014] FIG. 10B illustrates an example of how aggregated cells may be configured into one or morePUCCH groups.

[0015] FIG. 11A illustrates an example of an SS / PBCH block structure and location.

[0016] FIG. 11 B illustrates an example of CSI-RSs that are mapped in the time and frequency domains.

[0017] FIG. 12A and FIG. 12B respectively illustrate examples of three downlink and uplink beam management procedures.Docket No.: 24-1257PCT

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

[0019] FIG. 14A illustrates an example of CORESET configurations for a bandwidth part.

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

[0021] FIG. 15 illustrates an example of a wireless device in communication with a base station.

[0022] FIG. 16A, FIG. 16B, FIG. 16C, and FIG. 16D illustrate example structures for uplink and downlink transmission.

[0023] FIG. 17 illustrates an aspect of an example embodiment according to the present disclosure

[0024] FIG. 18 illustrates an aspect of an example embodiment according to the present disclosure.

[0025] FIG. 19 illustrates an aspect of an example embodiment according to the present disclosure.

[0026] FIG. 20 illustrates an aspect of an example embodiment according to the present disclosure.

[0027] FIG. 21 illustrates an aspect of an example embodiment according to the present disclosure.

[0028] FIG. 22 illustrates an aspect of an example embodiment according to the present disclosure

[0029] FIG. 23 illustrates an aspect of an example embodiment according to the present disclosure.

[0030] FIG. 24 illustrates an aspect of an example embodiment according to the present disclosure.

[0031] FIG. 25 illustrates an aspect of an example embodiment according to the present disclosure.

[0032] FIG. 26 illustrates an aspect of an example embodiment according to the present disclosure

[0033] FIG. 27 illustrates an aspect of an example embodiment according to the present disclosure.

[0034] FIG. 28 illustrates an aspect of an example embodiment according to the present disclosure.

[0035] FIG. 29 illustrates an aspect of an example embodiment according to the present disclosure.DETAILED DESCRIPTION

[0036] In the present disclosure, various embodiments are presented as examples of how the disclosed techniques may be implemented and / or how the disclosed techniques may be practiced in environments and scenarios. It will be apparent to persons skilled in the relevant art that various changes in form and detail can be made therein without departing from the scope. In fact, after reading the description, it will be apparent to one skilled in the relevant art how to implement alternative embodiments. The present embodiments should not be limited by any of the described exemplary embodiments. The embodiments of the present disclosure will be described with reference to the accompanying drawings. Limitations, features, and / or elements from the disclosed example embodiments may be combined to create further embodiments within the scope of the disclosure. Any figures which highlight the functionality and advantages, are presented for example purposes only. The disclosed architecture is sufficiently flexible andDocket No.: 24-1257PCT configurable, such that it may be utilized in ways other than that shown. For example, the actions listed in any flowchart may be re-ordered or only optionally used in some embodiments.

[0037] Embodiments may be configured to operate as needed. The disclosed mechanism may be performed when certain criteria are met, for example, in a wireless device, a base station, a radio environment, a network, a combination of the above, and / or the like. Example criteria may be based, at least in part, on for example, wireless device or network node configurations, traffic load, initial system set up, packet sizes, traffic characteristics, a combination of the above, and / or the like. When the one or more criteria are met, various example embodiments may be applied. Therefore, it may be possible to implement example embodiments that selectively implement disclosed protocols.

[0038] A base station may communicate with a mix of wireless devices. Wireless devices and / or base stations may support multiple technologies, and / or multiple releases of the same technology. Wireless devices may have some specific capability(ies) depending on wireless device category and / or capability(ies). When this disclosure refers to a base station communicating with a plurality of wireless devices, this disclosure may refer to a subset of the total wireless devices in a coverage area. This disclosure may refer to, for example, a plurality of wireless devices of a given LTE or 5G release with a given capability and in a given sector of the base station. The plurality of wireless devices in this disclosure may refer to a selected plurality of wireless devices, and / or a subset of total wireless devices in a coverage area which perform according to disclosed methods, and / or the like. There may be a plurality of base stations or a plurality of wireless devices in a coverage area that may not comply with the disclosed methods, for example, those wireless devices or base stations may perform based on older releases of LTE or 5G technology.

[0039] In this disclosure, “a” and “an’’ and similar phrases are to be interpreted as “at least one” and “one or more.” Similarly, any term that ends with the suffix “(s)” is to be interpreted as “at least one” and “one or more.” In this disclosure, the term “may” is to be interpreted as “may, for example.” In other words, the term “may” is indicative that the phrase following the term “may” is an example of one of a multitude of suitable possibilities that may, or may not, be employed by one or more of the various embodiments. The terms “comprises” and “consists of’, as used herein, enumerate one or more components of the element being described. The term “comprises” is interchangeable with “includes” and does not exclude unenumerated components from being included in the element being described. By contrast, “consists of' provides a complete enumeration of the one or more components of the element being described. The term “based on”, as used herein, should be interpreted as “based at least in part on” rather than, for example, “based solely on”. The term “and / or” as used herein represents any possible combination of enumerated elements. For example, “A, B, and / or C” may represent A; B; C; A and B; A and C; B and C; or A, B, and C.Docket No.: 24-1257PCT

[0040] If A and B are sets and every element of A is an element of B, A is called a subset of B. In this specification, only non-empty sets and subsets are considered. For example, possible subsets of B = {cell 1 , cell2} are: {celH }, {cell2}, and {celH , cell2}. The phrase “based on" (or equally “based at least on") is indicative that the phrase following the term “based on” is an example of one of a multitude of suitable possibilities that may, or may not, be employed to one or more of the various embodiments. The phrase “in response to” (or equally “in response at least to”) is indicative that the phrase following the phrase “in response to” is an example of one of a multitude of suitable possibilities that may, or may not, be employed to one or more of the various embodiments. The phrase “depending on” (or equally “depending at least to”) is indicative that the phrase following the phrase “depending on” is an example of one of a multitude of suitable possibilities that may, or may not, be employed to one or more of the various embodiments. The phrase “employing / using” (or equally “employing / using at least”) is indicative that the phrase following the phrase “employing / using" is an example of one of a multitude of suitable possibilities that may, or may not, be employed to one or more of the various embodiments.

[0041] The term configured may relate to the capacity of a device whether the device is in an operational or non-operational state. Configured may refer to specific settings in a device that affect or implement the operational characteristics of the device whether the device is in an operational or non-operational state. In other words, the hardware, software, firmware, registers, memory values, and / or the like may be “configured” within a device, whether the device is in an operational or nonoperational state, to provide the device with specific characteristics. Terms such as “a control message to cause in a device” may mean that a control message has parameters that may be used to configure specific characteristics or may be used to implement certain actions in the device, whether the device is in an operational or non-operational state.

[0042] In this disclosure, parameters (or equally called, fields, or Information elements: lEs) may comprise one or more information objects, and an information object may comprise one or more other objects. For example, if parameter (IE) N comprises parameter (IE) M, and parameter (IE) M comprises parameter (IE) K, and parameter (IE) K comprises parameter (information element) J. Then, for example, N comprises K, and N comprises J. In an example embodiment, when one or more messages comprise a plurality of parameters, it implies that a parameter in the plurality of parameters is in at least one of the one or more messages, but does not have to be in each of the one or more messages.

[0043] Many features presented are described as being optional through the use of “may” or the use of parentheses. For the sake of brevity and legibility, the present disclosure does not explicitly recite each and every permutation that may be obtained by choosing from the set of optional features. The present disclosure is to be interpreted as explicitly disclosing all such permutations. For example, a system described as having three optional features may be embodied in seven ways, namely with just one of theDocket No.: 24-1257PCT three possible features, with any two of the three possible features or with three of the three possible features.

[0044] Many of the elements described in the disclosed embodiments may be implemented as modules. A module is defined here as an element that performs a defined function and has a defined interface to other elements. The modules described in this disclosure may be implemented in hardware, software in combination with hardware, firmware, wetware (e.g., hardware with a biological element), or a combination thereof, which may be behaviorally equivalent. For example, modules may be implemented as a software routine written in a computer language configured to be executed by a hardware machine (such as C, C++, Fortran, Java, Basic, MATLAB or the like) or a modeling / simulation program such as Simulink, Stateflow, GNU Octave, or LabVIEWMathScript. It may be possible to implement modules using physical hardware that incorporates discrete or programmable analog, digital and / or quantum hardware. Examples of programmable hardware comprise: 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++ or the like. FPGAs, ASICs and CPLDs are often programmed using hardware description languages (HDL) such as VHSIC hardware description language (VHDL) or Verilog that configure connections between internal hardware modules with lesser functionality on a programmable device. The mentioned technologies are often used in combination to achieve the result of a functional module.

[0045] FIG. 1 A 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) run by a network operator. As illustrated in FIG. 1A, the mobile communication network 100 includes a core network (CN) 102, a radio access network (RAN) 104, and a wireless device 106.

[0046] The CN 102 may 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 intra-operator DNs. As part of the interface functionality, the CN 102 may set up end-to-end connections between the wireless device 106 and the one or more DNs, authenticate the wireless device 106, and provide charging functionality.

[0047] The RAN 104 may connect the CN 102 to the wireless device 106 through radio communications over an air interface. As part of the radio communications, the RAN 104 may provide scheduling, radio resource management, and retransmission protocols. The communication direction from the RAN 104 to the wireless device 106 over the air interface is known as the downlink and the communication direction from the wireless device 106 to the RAN 104 over the air interface is known as the uplink. DownlinkDocket No.: 24-1257PCT transmissions may be separated from uplink transmissions using frequency division duplexing (FDD), timedivision duplexing (TDD), and / or some combination of the two duplexing techniques.

[0048] The term wireless device may be used throughout this disclosure to refer to and encompass any mobile device or fixed (non-mobile) device for which wireless communication is needed or usable. For example, a wireless device may be a telephone, smart phone, tablet, computer, laptop, sensor, meter, wearable device, Internet of Things (loT) device, vehicle roadside unit (RSU), relay node, automobile, and / or any combination thereof. The term wireless device encompasses other terminology, including user equipment (UE), user terminal (UT), access terminal (AT), mobile station, handset, wireless transmit and receive unit (WTRU), and / or wireless communication device.

[0049] The 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 a Node B (associated with UMTS and / or 3G standards), an Evolved Node B (eNB, associated with E-UTRA and / or 4G standards), a remote radio head (RRH), a baseband processing unit coupled to one or more RRHs, a repeater node or relay node used to extend the coverage area of a donor node, a Next Generation Evolved Node B (ng-eNB), a Generation Node B (gNB, associated with NR and / or 5G standards), an access point (AP, associated with, for example, Wi-Fi or any other suitable wireless communication standard), and / or any combination thereof. A base station may comprise at least one gNB Central Unit (gNB-CU) and at least one a gNB Distributed Unit (gNB-DU).

[0050] A base station included in the RAN 104 may include one or more sets of antennas for communicating with the wireless device 106 over the air interface. For example, one or more of the base stations may include three sets of antennas to respectively control three cells (or sectors). The size of a cell may be determined by a range at which a receiver (e.g., a base station receiver) can successfully receive the transmissions from a transmitter (e.g., a wireless device transmitter) operating in the cell. Together, the cells of the base stations may provide radio coverage to the wireless device 106 over a wide geographic area to support wireless device mobility.

[0051] In addition to three-sector sites, other implementations of base stations are possible. For example, one or more of the base stations in the RAN 104 may be implemented as a sectored site with more or less than three sectors. One or more of the base stations in the RAN 104 may be implemented as an access point, as a baseband processing unit coupled to several remote radio heads (RRHs), and / or as a repeater or relay node used to extend the coverage area of a donor node. A baseband processing unit coupled to RRHs may be part of a centralized or cloud RAN architecture, where the baseband processing unit may be either centralized in a pool of baseband processing units or virtualized. A repeater node may amplify and rebroadcast a radio signal received from a donor node. A relay node may perform the same / similarDocket No.: 24-1257PCT functions as a repeater node but may decode the radio signal received from the donor node to remove noise before amplifying and rebroadcasting the radio signal.

[0052] The RAN 104 may be deployed as a homogenous network of macrocell base stations that have similar antenna patterns and similar high-level transmit powers. The RAN 104 may be deployed as a heterogeneous network. In heterogeneous networks, small cell base stations may be used to provide small coverage areas, for example, coverage areas that overlap with the comparatively larger coverage areas provided by macrocell base stations. The small coverage areas may be provided in areas with high data traffic (or so-called “hotspots”) or in areas with weak macrocell coverage. Examples of small cell base stations include, in order of decreasing coverage area, microcell base stations, picocell base stations, and femtocell base stations or home base stations.

[0053] The Third-Generation Partnership Project (3GPP) was formed in 1998 to provide global standardization of specifications for mobile communication networks similar to the mobile communication network 100 in FIG. 1A. To date, 3GPP has produced specifications for three generations of mobile networks: a third generation (3G) network known as Universal Mobile Telecommunications System (UMTS), a fourth generation (4G) network known as Long-Term Evolution (LTE), and a fifth generation (5G) network known as 5G System (5GS). Embodiments of the present disclosure are described with reference to the RAN of a 3GPP 5G network, referred to as next-generation RAN (NG-RAN). Embodiments may be applicable to RANs of other mobile communication networks, such as the RAN 104 in FIG. 1A, the RANs of earlier 3G and 4G networks, and those of future networks yet to be specified (e.g., a 3GPP 6G network). NG-RAN implements 5G radio access technology known as New Radio (NR) and may be provisioned to implement 4G radio access technology or other radio access technologies, including non- 3GPP radio access technologies.

[0054] FIG. 1 B illustrates another example mobile communication network 150 in which embodiments of the present disclosure may be implemented. Mobile communication network 150 may be, for example, a PLMN run by a network operator. As illustrated in FIG. 1 B, mobile communication network 150 includes a 5G core network (5G-CN) 152, an NG-RAN 154, and UEs 156A and 156B (collectively UEs 156). These components may be implemented and operate in the same or similar manner as corresponding components described with respect to FIG 1 A.

[0055] The 5G-CN 152 provides the UEs 156 with an interface to one or more DNs, such as public DNs (e.g., the Internet), private DNs, and / or intra-operator DNs. As part of the interface functionality, the 5G-CN 152 may set up end-to-end connections between the UEs 156 and the one or more DNs, authenticate the UEs 156, and provide charging functionality. Compared to the CN of a 3GPP 4G network, the basis of the 5G-CN 152 may be a service-based architecture. This means that the architecture of the nodes making up the 5G-CN 152 may be defined as network functions that offer services via interfaces to other networkDocket No.: 24-1257PCT functions. The network functions of the 5G-CN 152 may 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).

[0056] As illustrated in FIG. 1 B, the 5G-CN 152 includes an Access and Mobility Management Function (AMF) 158A and a User Plane Function (UPF) 158B, which are shown as one component AMF / UPF 158 in FIG. 1 B for ease of illustration. The UPF 158B may serve as a gateway between the NG-RAN 154 and the one or more DNs. The UPF 158B may perform functions such as packet routing and forwarding, packet inspection and user plane policy rule enforcement, traffic usage reporting, uplink classification to support routing of traffic flows to the one or more DNs, quality of service (QoS) handling for the user plane (e.g., packet filtering, gating, uplink / downlink rate enforcement, and uplink traffic verification), downlink packet buffering, and downlink data notification triggering. The UPF 158B may serve as an anchor point for intra- / inter-Radio Access Technology (RAT) mobility, an external protocol (or packet) data unit (PDU) session point of interconnect to the one or more DNs, and / or a branching point to support a multi-homed PDU session. The UEs 156 may be configured to receive services through a PDU session, which is a logical connection between a UE and a DN

[0057] The AMF 158A may perform functions such as Non-Access Stratum (NAS) signaling termination, NAS signaling security, Access Stratum (AS) security control, inter-CN node signaling for mobility between 3GPP access networks, idle mode UE reachability (e.g., control and execution of paging retransmission), registration area management, intra-system and inter-system mobility support, access authentication, access authorization including checking of roaming rights, mobility management control (subscription and policies), network slicing support, and / or session management function (SMF) selection. NAS may refer to the functionality operating between a CN and a UE, and AS may refer to the functionality operating between the UE and a RAN.

[0058] The 5G-CN 152 may include one or more additional network functions that are not shown in FIG 1 B for the sake of clarity. For example, the 5G-CN 152 may include one or more of a Session Management Function (SMF), an NR Repository Function (NRF), a Policy Control Function (PCF), a Network Exposure Function (NEF), a Unified Data Management (UDM), an Application Function (AF), and / or an Authentication Server Function (AUSF).

[0059] The NG-RAN 154 may connect the 5G-CN 152 to the UEs 156 through radio communications over the air interface. The NG-RAN 154 may include one or more gNBs, illustrated as gNB 160A and gNB 160B (collectively gNBs 160) and / or one or more ng-eNBs, illustrated as ng-eNB 162A and ng-eNB 162B (collectively ng-eNBs 162). The gNBs 160 and ng-eNBs 162 may be more generically referred to as base stations. The gNBs 160 and ng-eNBs 162 may include one or more sets of antennas for communicating with the UEs 156 over an air interface. For example, one or more of the gNBs 160 and / or one or more ofDocket No.: 24-1257PCT the ng-eNBs 162 may include three sets of antennas to respectively control three cells (or sectors). Together, the cells of the gNBs 160 and the ng-eNBs 162 may provide radio coverage to the UEs 156 over a wide geographic area to support UE mobility.

[0060] As shown in FIG. 1 B, the gNBs 160 and / or the ng-eNBs 162 may be connected to the 5G-CN 152 by means of an NG interface and to other base stations by an Xn interface. The NG and Xn interfaces may be established using direct physical connections and / or indirect connections over an underlying transport network, such as an internet protocol (IP) transport network. The gNBs 160 and / or the ng-eNBs 162 may be connected to the UEs 156 by means of a Uu interface. For example, as illustrated in FIG. 1 B, gNB 160A may be connected to the UE 156A by means of a Uu interface. The NG, Xn, and Uu interfaces are associated with a protocol stack. The protocol stacks associated with the interfaces may be used by the network elements in FIG. 1 B to exchange data and signaling messages and may include two planes: a user plane and a control plane. The user plane may handle data of interest to a user. The control plane may handle signaling messages of interest to the network elements.

[0061] The gNBs 160 and / or the ng-eNBs 162 may be connected to one or more AMF / UPF functions of the 5G-CN 152, such as the AMF / UPF 158, by means of one or more NG interfaces. For example, the gNB 160A may be connected to the UPF 158B of the AMF / UPF 158 by means of an NG-User plane (NG-U) interface. The NG-U interface may provide delivery (e.g., non-guaranteed delivery) of user plane PDUs between the gNB 160A and the UPF 158B. The gNB 160A may be connected to the AMF 158A by means of an NG-Control plane (NG-C) interface. The NG-C interface may provide, for example, NG interface management, UE context management, UE mobility management, transport of NAS messages, paging, PDU session management, and configuration transfer and / or warning message transmission.

[0062] The gNBs 160 may provide NR user plane and control plane protocol terminations towards the UEs 156 over the Uu interface. For example, the gNB 160A may provide NR user plane and control plane protocol terminations toward the UE 156A over a Uu interface associated with a first protocol stack. The ng- eNBs 162 may provide Evolved UMTS Terrestrial Radio Access (E-UTRA) user plane and control plane protocol terminations towards the UEs 156 over a Uu interface, where E-UTRA refers to the 3GPP 4G radio-access technology. For example, the ng-eNB 162B may provide E-UTRA user plane and control plane protocol terminations towards the UE 156B over a Uu interface associated with a second protocol stack.

[0063] The 5G-CN 152 was described as being configured to handle NR and 4G radio accesses. It will be appreciated by one of ordinary skill in the art that it may be possible for NR to connect to a 4G core network in a mode known as “non-standalone operation.” In non-standalone operation, a 4G core network is used to provide (or at least support) control-plane functionality (e.g., initial access, mobility, and paging). AlthoughDocket No.: 24-1257PCT only one AMF / UPF 158 is shown in FIG. 1 B, one gNB or ng-eNB may be connected to multiple AMF / UPF nodes to provide redundancy and / or to load share across the multiple AMF / UPF nodes.

[0064] As discussed, an interface (e.g., Uu, Xn, and NG interfaces) between the network elements in FIG. 1 B may be associated with a protocol stack that the network elements use to exchange data and signaling messages. A protocol stack may include two planes: a user plane and a control plane. The user plane may handle data of interest to a user, and the control plane may handle signaling messages of interest to the network elements.

[0065] FIG. 2A and FIG. 2B respectively illustrate examples of NR user plane and NR control plane protocol stacks for the Uu interface that lies between a UE 210 and a gNB 220. The protocol stacks illustrated in FIG. 2A and FIG. 2B may be the same or similar to those used for the Uu interface between, for example, the UE 156A and the gNB 160A shown in FIG. 1 B.

[0066] FIG. 2A illustrates a NR user plane protocol stack comprising five layers implemented in the UE 210 and the gNB 220. At the bottom of the protocol stack, physical layers (PHYs) 211 and 221 may provide transport services to the higher layers of the protocol stack and may correspond to layer 1 of the Open Systems Interconnection (OSI) model. The next four protocols above PHYs 211 and 221 comprise media access control layers (MACs) 212 and 222, radio link control layers (RLCs) 213 and 223, packet data convergence protocol layers (PDCPs) 214 and 224, and service data application protocol layers (SDAPs) 215 and 225. Together, these four protocols may make up layer 2, or the data link layer, of the OSI model.

[0067] FIG. 3 illustrates an example of services provided between protocol layers of the NR user plane protocol stack. Starting from the top of FIG. 2A and FIG. 3, the SDAPs 215 and 225 may perform QoS flow handling. The UE 210 may receive services through a PDU session, which may be a logical connection between the UE 210 and a DN. The PDU session may have one or more QoS flows. A UPF of a CN (e.g., the UPF 158B) may map IP packets to the one or more QoS flows of the PDU session based on QoS requirements (e.g., in terms of delay, data rate, and / or error rate). The SDAPs 215 and 225 may perform mapping / de-mapping between the one or more QoS flows and one or more data radio bearers. The mapping / de-mapping between the QoS flows and the data radio bearers may be determined by the SDAP 225 at the gNB 220. The SDAP 215 at the UE 210 may be informed of the mapping between the QoS flows and the data radio bearers through reflective mapping or control signaling received from the gNB 220. For reflective mapping, the SDAP 225 at the gNB 220 may mark the downlink packets with a QoS flow indicator (QFI), which may be observed by the SDAP 215 at the UE 210 to determine the mapping / de-mapping between the QoS flows and the data radio bearers.

[0068] The PDCPs 214 and 224 may perform header compression / decompression to reduce the amount of data that needs to be transmitted over the air interface, ciphering / deciphering to prevent unauthorized decoding of data transmitted over the air interface, and integrity protection (to ensure control messagesDocket No.: 24-1257PCT originate from intended sources The PDCPs 214 and 224 may perform retransmissions of undelivered packets, in-sequence delivery and reordering of packets, and removal of packets received in duplicate due to, for example, an intra-g NB handover. The PDCPs 214 and 224 may perform packet duplication to improve the likelihood of the packet being received and, at the receiver, remove any duplicate packets. Packet duplication may be useful for services that require high reliability.

[0069] Although not shown in FIG. 3, PDCPs 214 and 224 may perform mapping / de-mapping between a split radio bearer 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, two cell groups: a master cell group (MCG) and a secondary cell group (SCG). A split bearer is when a single radio bearer, such as one of the radio bearers provided by the PDCPs 214 and 224 as a service to the SDAPs 215 and 225, is handled by cell groups in dual connectivity. The PDCPs 214 and 224 may map / de-map the split radio bearer between RLC channels belonging to cell groups.

[0070] The RLCs 213 and 223 may perform segmentation, retransmission through Automatic Repeat Request (ARQ), and removal of duplicate data units received from MACs 212 and 222, respectively. The RLCs 213 and 223 may support three transmission modes: transparent mode (TM); unacknowledged mode (UM); and acknowledged mode (AM). Based on the transmission mode an RLC is operating, the RLC may perform one or more of the noted functions. The RLC configuration may be per logical channel with no dependency on numerologies and / or Transmission Time Interval (TTI) durations. As shown in FIG. 3, the RLCs 213 and 223 may provide RLC channels as a service to PDCPs 214 and 224, respectively.

[0071] The MACs 212 and 222 may perform multiplexing / demultiplexing of logical channels and / or mapping between logical channels and transport channels. The multiplexing / demultiplexing may include multiplexing / demultiplexing of data units, belonging to the one or more logical channels, into / from Transport Blocks (TBs) delivered to / from the PHYs 211 and 221 . The MAC 222 may be configured to perform scheduling, scheduling information reporting, and priority handling between UEs by means of dynamic scheduling. Scheduling may be performed in the gNB 220 (at the MAC 222) for downlink and uplink. The MACs 212 and 222 may be configured to perform error correction through Hybrid Automatic Repeat Request (HARQ) (e.g., one HARQ entity per carrier in case of Carrier Aggregation (CA)), priority handling between logical channels of the UE 210 by means of logical channel prioritization, and / or padding. The MACs 212 and 222 may support one or more numerologies and / or transmission timings. In an example, mapping restrictions in a logical channel prioritization may control which numerology and / or transmission timing a logical channel may use. As shown in FIG. 3, the MACs 212 and 222 may provide logical channels as a service to the RLCs 213 and 223.

[0072] The PHYs 211 and 221 may perform mapping of transport channels to physical channels and digital and analog signal processing functions for sending and receiving information over the air interface.Docket No.: 24-1257PCTThese digital and analog signal processing functions may include, for example, coding / decoding and modulation / demodulation. The PHYs 211 and 221 may perform multi-antenna mapping. As shown in FIG. 3, the PHYs 211 and 221 may provide one or more transport channels as a service to the MACs 212 and 222.

[0073] FIG. 4A illustrates an example downlink data flow through the NR user plane protocol stack. FIG. 4A illustrates a downlink data flow of three IP packets (n, n+1 , and m) through the NR user plane protocol stack to generate two TBs at the gNB 220. An uplink data flow through the NR user plane protocol stack may be similar to the downlink data flow depicted in FIG. 4A.

[0074] The downlink data flow of FIG. 4A begins when SDAP 225 receives the three IP packets from one or more QoS flows and maps the three packets to radio bearers In FIG. 4A, the SDAP 225 maps IP packets n and n+1 to a first radio bearer 402 and maps IP packet m to a second radio bearer 404. An SDAP header (labeled with an “H” in FIG. 4A) is added to an IP packet. The data unit from / to a higher protocol layer is referred to as a service data unit (SDU) of the lower protocol layer and the data unit to / from a lower protocol layer is referred to as a protocol data unit (PDU) of the higher protocol layer. As shown in FIG 4A, the data unit from the SDAP 225 is an SDU of lower protocol layer PDCP 224 and is a PDU of the SDAP 225.

[0075] The remaining protocol layers in FIG. 4A may perform their associated functionality (e.g., with respect to FIG. 3), add corresponding headers, and forward their respective outputs to the next lower layer. For example, the PDCP 224 may perform IP-header compression and ciphering and forward its output to the RLC 223. The RLC 223 may optionally perform segmentation (e.g., as shown for IP packet m in FIG. 4A) and forward its output to the MAC 222. The MAC 222 may multiplex a number of RLC PDUs and may attach a MAC subheader to an RLC PDU to form a transport block. In NR, the MAC subheaders may be distributed across the MAC PDU, as illustrated in FIG. 4A. In LTE, the MAC subheaders may be entirely located at the beginning of the MAC PDU. The NR MAC PDU structure may reduce processing time and associated latency because the MAC PDU subheaders may be computed before the full MAC PDU is assembled.

[0076] FIG. 4B illustrates an example format of a MAC subheader in a MAC PDU. The MAC subheader includes: an SDU length field for indicating the length (e.g., in bytes) of the MAC SDU to which the MAC subheader corresponds; a logical channel identifier (LCID) field for identifying the logical channel from which the MAC SDU originated to aid in the demultiplexing process; a flag (F) for indicating the size of the SDU length field; and a reserved bit (R) field for future use.

[0077] FIG. 4B further illustrates MAC control elements (CEs) inserted into the MAC PDU by a MAC, such as MAC 212 or MAC 222 For example, FIG. 4B illustrates two MAC CEs inserted into the MAC PDU. MAC CEs may be inserted at the beginning of a MAC PDU for downlink transmissions (as shown in FIG. 4B) andDocket No.: 24-1257PCT at the end of a MAC PDU for uplink transmissions. MAC CEs may be used for in-band control signaling. Example MAC CEs include: scheduling-related MAC CEs, such as buffer status reports and power headroom reports; activation / deactivation MAC CEs, such as those for activation / deactivation of PDCP duplication detection, channel state information (CSI) reporting, sounding reference signal (SRS) transmission, and prior configured components; discontinuous reception (DRX) related MAC CEs; timing advance MAC CEs; and random access related MAC CEs. A MAC CE may be preceded by a MAC subheader with a similar format as described for MAC SDUs and may be identified with a reserved value in the LCID field that indicates the type of control information included in the MAC CE.

[0078] Before describing the NR control plane protocol stack, logical channels, transport channels, and physical channels are first described as well as a mapping between the channel types. One or more of the channels may be used to carry out functions associated with the NR control plane protocol stack described later below.

[0079] FIG. 5A and FIG. 5B illustrate, for downlink and uplink respectively, a mapping between logical channels, transport channels, and physical channels. Information is passed through channels between the RLC, the MAC, and the PHY of the NR protocol stack. A logical channel may be used between the RLC and the MAC and may be classified as a control channel that carries control and configuration information in the NR control plane or as a traffic channel that carries data in the NR user plane. A logical channel may be classified as a dedicated logical channel that is dedicated to a specific UE or as a common logical channel that may be used by more than one UE. A logical channel may also be defined by the type of information it carries. The set of logical channels defined by NR includes, for example:

[0080] - a paging control channel (PCCH) for carrying paging messages used to page a UE whose location is not known to the network on a cell level;

[0081] - a broadcast control channel (BCCH) for carrying system information messages in the form of a master information block (MIB) and several system information blocks (SIBs), wherein the system information messages may be used by the UEs to obtain information about how a cell is configured and how to operate within the cell;

[0082] - a common control channel (CCCH) for carrying control messages together with random access;

[0083] - a dedicated control channel (DCCH) for carrying control messages to / from a specific the UE to configure the UE; and

[0084] - a dedicated traffic channel (DTCH) for carrying user data to / from a specific the UE.

[0085] Transport channels are used between the MAC and PHY layers and may 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:

[0086] - a paging channel (PCH) for carrying paging messages that originated from the PCCH;Docket No.: 24-1257PCT

[0087] - a broadcast channel (BCH) for carrying the M IB from the BCCH;

[0088] - a downlink shared channel (DL-SCH) for carrying downlink data and signaling messages, including the SIBs from the BCCH;

[0089] - an uplink shared channel (UL-SCH) for carrying uplink data and signaling messages; and

[0090] - a random access channel (RACH) for allowing a UE to contact the network without any prior scheduling.

[0091] The PHY may use physical channels to pass information between processing levels of the PHY. A physical channel may have an associated set of time-frequency resources for carrying the information of one or more transport channels. The PHY may generate control information to support the low-level operation of the PHY and provide the control information to the lower levels of the PHY via physical control channels, known as L1 / L2 control channels. The set of physical channels and physical control channels defined by NR includes, for example:

[0092] - a physical broadcast channel (PBCH) for carrying the MIB from the BCH;

[0093] - a physical downlink shared channel (PDSCH) for carrying downlink data and signaling messages from the DL-SCH, as well as paging messages from the PCH;

[0094] - a physical downlink control channel (PDCCH) for carrying downlink control information (DCI), which may include downlink scheduling commands, uplink scheduling grants, and uplink power control commands;

[0095] - a physical uplink shared channel (PUSCH) for carrying uplink data and signaling messages from the UL-SCH and in some instances uplink control information (UCI) as described below;

[0096] - a physical uplink control channel (PUCCH) for carrying UCI, which may include HARQ acknowledgments, channel quality indicators (CQI), pre-coding matrix indicators (PM I), rank indicators (Rl), and scheduling requests (SR); and

[0097] - a physical random access channel (PRACH) for random access.

[0098] Similar to the physical control channels, the physical layer generates physical signals to support the low-level operation of the physical layer. As shown in FIG. 5A and FIG. 5B, the physical layer signals defined by NR include: primary synchronization signals (PSS), secondary synchronization signals (SSS), channel state information reference signals (CSI-RS), demodulation reference signals (DMRS), sounding reference signals (SRS), and phase-tracking reference signals (PT-RS). These physical layer signals will be described in greater detail below.

[0099] FIG. 2B illustrates an example NR control plane protocol stack. As shown in FIG. 2B, the NR control plane protocol stack may use the same / similar first four protocol layers as the example NR user plane protocol stack. These four protocol layers include the PHYs 211 and 221 , the MACs 212 and 222, the RLCs 213 and 223, and the PDCPs 214 and 224. Instead of having the SDAPs 215 and 225 at the top ofDocket No.: 24-1257PCT the stack as in the NR user plane protocol stack, the NR control plane stack has radio resource controls (RRCs) 216 and 226 and NAS protocols 217 and 237 at the top of the NR control plane protocol stack.

[0100] The NAS protocols 217 and 237 may provide control plane functionality between the UE 210 and the AMF 230 (e.g., the AMF 158A) or, more generally, between the UE 210 and the CN. The NAS protocols 217 and 237 may provide control plane functionality between the UE 210 and the AMF 230 via signaling messages, referred to as NAS messages. There is no direct path between the UE 210 and the AMF 230 through which the NAS messages can be transported. The NAS messages may be transported using the AS of the Uu and NG interfaces. NAS protocols 217 and 237 may provide control plane functionality such as authentication, security, connection setup, mobility management, and session management.

[0101] The RRCs 216 and 226 may provide control plane functionality between the UE 210 and the gNB 220 or, more generally, between the UE 210 and the RAN. The RRCs 216 and 226 may provide control plane functionality between the UE 210 and the gNB 220 via signaling messages, referred to as RRC messages. RRC messages may be transmitted between the UE 210 and the RAN using signaling radio bearers and the same / similar PDCP, RLC, MAC, and PHY protocol layers. The MAC may multiplex controlplane and user-plane data into the same transport block (TB). The RRCs 216 and 226 may provide control plane functionality such as: broadcast of system information related to AS and NAS; paging initiated by the CN or the RAN; establishment, maintenance and release of an RRC connection between the UE 210 and the RAN; security functions including key management; establishment, configuration, maintenance and release of signaling radio bearers and data radio bearers; mobility functions; QoS management functions; the UE measurement reporting and control of the reporting; detection of and recovery from radio link failure (RLF); and / or NAS message transfer. As part of establishing an RRC connection, RRCs 216 and 226 may establish an RRC context, which may involve configuring parameters for communication between the UE 210 and the RAN .

[0102] FIG. 6 is an example diagram showing RRC state transitions of a UE. The UE may be the same or similar to the wireless device 106 depicted in FIG. 1A, the UE 210 depicted in FIG. 2A and FIG. 2B, or any other wireless device described in the present disclosure. As illustrated in FIG. 6, a UE may be in at least one of three RRC states: RRC connected 602 (e.g., RRC_CONNECTED), RRC idle 604 (e.g., RRC_I DEE), and RRC inactive 606 (e.g., RRCJNACTIVE).

[0103] In RRC connected 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 of the one or more base stations included in the RAN 104 depicted in FIG. 1A, one of the gNBs 160 or ng-eNBs 162 depicted in FIG. 1 B, the gNB 220 depicted in FIG. 2A and FIG. 2B, or any other base station described in the present disclosure. The base station with which the UE is connected may have the RRC context for the UE. The RRC context, referred to as the UE context, may comprise parameters for communication between the UE and the baseDocket No.: 24-1257PCT 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 a data radio bearer, signaling radio bearer, logical channel, QoS flow, and / or PDU session); security information; and / or PHY, MAC, RLC, PDCP, and / or SDAP layer configuration information. While in RRC connected 602, mobility of the UE may be managed by the RAN (e.g., the RAN 104 or the NG-RAN 154). The UE may measure the signal levels (e.g., reference signal levels) from a serving cell and neighboring cells and report these measurements to the base station currently serving the UE. The UE's serving base station may request a handover to a cell of one of the neighboring base stations based on the reported measurements. The RRC state may transition from RRC connected 602 to RRC idle 604 through a connection release procedure 608 or to RRC inactive 606 through a connection inactivation procedure 610.

[0104] In RRC idle 604, an RRC context may not be established for the UE. In RRC idle 604, the UE may not have an RRC connection with the base station. While in RRC idle 604, the UE may be in a sleep state for the majority of the time (e.g., to conserve battery power). The UE may wake up periodically (e.g., once in every discontinuous reception cycle) to monitor for paging messages from the RAN. Mobility of the UE may be managed by the UE through a procedure known as cell reselection. The RRC state may transition from RRC idle 604 to RRC connected 602 through a connection establishment procedure 612, which may involve a random access procedure as discussed in greater detail below.

[0105] In RRC inactive 606, the RRC context previously established is maintained in the UE and the base station. This allows for a fast transition to RRC connected 602 with reduced signaling overhead as compared to the transition from RRC idle 604 to RRC connected 602. While in RRC inactive 606, the UE may be in a sleep state and mobility of the UE may be managed by the UE through cell reselection. The RRC state may transition from RRC inactive 606 to RRC connected 602 through a connection resume procedure 614 or to RRC idle 604 though a connection release procedure 616 that may be the same as or similar to connection release procedure 608.

[0106] An RRC state may be associated with a mobility management mechanism. 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 be able to notify the UE of an event via a paging message without having to broadcast the paging message over the entire mobile communications network. The mobility management mechanism used in RRC idle 604 and RRC inactive 606 may allow the network to track the UE on a cell-group level so that the paging message may be broadcast over the cells of the cell group that the UE currently resides within instead of the entire mobile communication network. The mobility management mechanisms for RRC idle 604 and RRC inactive 606 track the UE on a cell-group level. They may do so using different granularities of grouping. For example, there may be three levels of cell-grouping granularity: individual cells; cells within a RAN area identified byDocket No.: 24-1257PCT a RAN area identifier (RAI); and cells within a group of RAN areas, referred to as a tracking area and identified by a tracking area identifier (TAI).

[0107] Tracking areas may be used to track the UE at the CN level. The CN (e.g., the CN 102 or the 5G-CN 152) may provide the UE with a list of TAIs associated with a UE registration area. If the UE moves, through cell reselection, to a cell associated with a TAI not included in the list of TAIs associated with the UE registration area, the UE may perform a registration update with the CN to allow the CN to update the UE's location and provide the UE with a new the UE registration area.

[0108] RAN areas may be used to track the UE at the RAN level. For a UE in RRC inactive 606 state, the UE may be assigned a RAN notification area. A RAN notification area may comprise one or more cell identities, a list of RAIs, or a list of TAIs. In an example, a base station may belong to one or more RAN notification areas. In an example, a cell may belong to one or more RAN notification areas. If the UE moves, through cell reselection, to a cell not included in the RAN notification area assigned to the UE, the UE may perform a notification area update with the RAN to update the UE’s RAN notification area.

[0109] A base station storing an RRC context for a UE or a last serving base station of the UE may be referred to as an anchor base station. An anchor base station may maintain an RRC context for the UE at least during a period of time that the UE stays in a RAN notification area of the anchor base station and / or during a period of time that the UE stays in RRC inactive 606.

[0110] A gNB, such as gNBs 160 in FIG. 1 B, may be split into two parts: a central unit (gNB-CU), and one or more distributed units (gNB-DU). A gNB-CU may be coupled to one or more gNB-DUs using an F1 interface. The gNB-CU may comprise the RRC, the PDCP, and the SDAP. A gNB-DU may comprise the RLC, the MAC, and the PHY.

[0111] In NR, the physical signals and physical channels (discussed with respect to FIG. 5A and FIG. 5B) may be mapped onto orthogonal frequency divisional multiplexing (OFDM) symbols. OFDM is a multicarrier communication scheme that transmits data over F orthogonal subcarriers (or tones). Before transmission, the data may be mapped to a series of complex symbols (e.g., M-quadrature amplitude modulation (M- QAM) or M-phase shift keying (M-PSK) symbols), referred to as source symbols, and divided into F parallel symbol streams. The F parallel symbol streams may be treated as though they are in the frequency domain and used as inputs to an Inverse Fast Fourier Transform (IFFT) block that transforms them into the time domain. The IFFT block may take in F source symbols at a time, one from each of the F parallel symbol streams, and use each source symbol to modulate the amplitude and phase of one of F sinusoidal basis functions that correspond to the F orthogonal subcarriers. The output of the IFFT block may be F timedomain samples that represent the summation of the F orthogonal subcarriers. The F time-domain samples may form a single OFDM symbol. After some processing (e.g., addition of a cyclic prefix) and up- conversion, an OFDM symbol provided by the IFFT block may be transmitted over the air interface on aDocket No.: 24-1257PCT carrier frequency. The F parallel symbol streams may be mixed using an FFT block before being processed by the IFFT block. This operation produces Discrete Fourier Transform (DFT)-precoded OFDM symbols and may be used by UEs in the uplink to reduce the peak to average power ratio (PAPR). Inverse processing may be performed on the OFDM symbol at a receiver using an FFT block to recover the data mapped to the source symbols.

[0112] FIG. 7 illustrates an example configuration of an NR frame into which OFDM symbols are grouped. An NR frame may be identified by a system frame number (SFN). The SFN may repeat with a period of 1024 frames. As illustrated, one NR frame may be 10 milliseconds (ms) in duration and may include 10 subframes that are 1 ms in duration. A subframe may be divided into slots that include, for example, 14 OFDM symbols per slot.

[0113] The duration of a slot may depend on the numerology used for the OFDM symbols of the slot. In NR, a flexible numerology is supported to accommodate different cell deployments (e.g., cells with carrier frequencies below 1 GHz up to cells with carrier frequencies in the mm-wave range). A numerology may be defined in terms of subcarrier spacing and cyclic prefix duration. For a numerology in NR, subcarrier spacings may be scaled up by powers of two from a baseline subcarrier spacing of 15 kHz, and cyclic prefix durations may be scaled down by powers of two from a baseline cyclic prefix duration of 4.7 ps. For example, NR defines numerologies with the following subcarrier spacing / cyclic prefix duration combinations: 15 kHz / 4.7 ps; 30 kHz / 2.3 ps; 60 kHz / 1.2 ps; 120 kHz / 0.59 ps; and 240 kHz / 0.29 ps.

[0114] A slot may have a fixed number of OFDM symbols (e.g., 14 OFDM symbols). A numerology with a higher subcarrier spacing has a shorter slot duration and, correspondingly, more slots per subframe. FIG. 7 illustrates this numerology-dependent slot duration and slots-per-subframe transmission structure (the numerology with a subcarrier spacing of 240 kHz is not shown in FIG. 7 for ease of illustration). A subframe in NR may be used as a numerology-independent time reference, while a slot may be used as the unit upon which uplink and downlink transmissions are scheduled. To support low latency, scheduling in NR may be decoupled from the slot duration and start at any OFDM symbol and last for as many symbols as needed for a transmission. These partial slot transmissions may be referred to as mini-slot or subslot transmissions.

[0115] FIG. 8 illustrates an example configuration of a slot in the time and frequency domain for an NR carrier. The slot includes resource elements (REs) and resource blocks (RBs). An RE is the smallest physical resource in NR. An RE spans one OFDM symbol in the time domain by one subcarrier in the frequency domain as shown in FIG. 8. An RB spans twelve consecutive REs in the frequency domain as shown in FIG. 8. An NR carrier may be limited to a width of 275 RBs or 275x12 = 3300 subcarriers. Such a limitation, if used, may limit the NR carrier to 50, 100, 200, and 400 MHz for subcarrier spacingsDocket No.: 24-1257PCT of 15, 30, 60, and 120 kHz, respectively, where the 400 MHz bandwidth may be set based on a 400 MHz per carrier bandwidth limit.

[0116] FIG. 8 illustrates a single numerology being used across the entire bandwidth of the NR carrier. In other example configurations, multiple numerologies may be supported on the same carrier.

[0117] NR may support wide carrier bandwidths (e.g., up to 400 MHz for a subcarrier spacing of 120 kHz). Not all UEs may be able to receive the full carrier bandwidth (e.g., due to hardware limitations). Also, receiving the full carrier bandwidth may be prohibitive in terms of UE power consumption. In an example, to reduce power consumption and / or for other purposes, a UE may adapt the size of the UE’s receive bandwidth based on the amount of traffic the UE is scheduled to receive. This is referred to as bandwidth adaptation.

[0118] NR defines bandwidth parts (BWPs) to support UEs not capable of receiving the full carrier bandwidth and to support bandwidth adaptation. In an example, a BWP may be defined by a subset of contiguous RBs on a carrier. A UE may be configured (e.g., via RRC layer) with 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 a serving cell may be active. These one or more BWPs may be referred to as active BWPs of the serving cell. When a serving cell is configured with a secondary uplink carrier, the serving cell may have one or more first active BWPs in the uplink carrier and one or more second active BWPs in the secondary uplink carrier.

[0119] For unpaired spectra, a downlink BWP from a set of configured downlink BWPs may be linked with an uplink BWP from a set of configured uplink BWPs if a downlink BWP index of the downlink BWP and an uplink BWP index of the uplink BWP are the same. For unpaired spectra, a UE may expect that a center frequency for a downlink BWP is the same as a center frequency for an uplink BWP.

[0120] For a downlink BWP in a set of configured downlink BWPs on a primary cell (PCell), a base station may configure a UE with one or more control resource sets (CORESETs) for at least one search space. A search space is a set of locations in the time and frequency domains where the UE may find control information. The search space may be a UE-specific search space or a common search space (potentially usable by a plurality of UEs). For example, a base station may configure a UE with a common search space, on a PCell or on a primary secondary cell (PSCell), in an active downlink BWP.

[0121] For an uplink BWP in a set of configured uplink BWPs, a BS may configure a UE with one or more resource sets for one or more PUCCH transmissions. A UE may receive downlink receptions (e.g., PDCCH or PDSCH) in a downlink BWP according to a configured numerology (e.g., subcarrier spacing and cyclic prefix duration) for the downlink BWP. The UE may transmit uplink transmissions (e.g., PUCCH or PUSCH) in an uplink BWP according to a configured numerology (e.g., subcarrier spacing and cyclic prefix length for the uplink BWP).Docket No.: 24-1257PCT

[0122] One or more BWP indicator fields may be provided in Downlink Control Information (DCI). A value of a BWP indicator field may indicate which BWP in a set of configured BWPs is an active downlink BWP for one or more downlink receptions. The value of the one or more BWP indicator fields may indicate an active uplink BWP for one or more uplink transmissions.

[0123] A base station may semi-statically configure a UE with a default downlink BWP within a set of configured downlink BWPs associated with a PCell. If the base station does not provide the default downlink BWP to the UE, the default downlink BWP may be an initial active downlink BWP. The UE may determine which BWP is the initial active downlink BWP based on a CORESET configuration obtained using the PBCH.

[0124] A base station may configure a UE with a BWP inactivity timer value for a PCell. The UE may start or restart a BWP inactivity timer at any appropriate time. For example, the UE may start or restart the BWP inactivity timer (a) when the UE detects a DCI indicating an active downlink BWP other than a default downlink BWP for a paired spectra operation; or (b) when a UE detects a DCI indicating an active downlink BWP or active uplink BWP other than a default downlink BWP or uplink BWP for an unpaired spectra operation. If the UE does not detect DCI during an interval of time (e.g., 1 ms or 0.5 ms), the UE may run the BWP inactivity timer toward expiration (for example, increment from zero to the BWP inactivity timer value, or decrement from the BWP inactivity timer value to zero). When the BWP inactivity timer expires, the UE may switch from the active downlink BWP to the default downlink BWP.

[0125] In an example, a base station may semi-statically configure a UE with one or more BWPs. A UE may switch an active BWP from a first BWP to a second BWP in response to receiving a DCI indicating the second BWP as an active BWP and / or in response to an expiry of the BWP inactivity timer (e.g., if the second BWP is the default BWP).

[0126] Downlink and uplink BWP switching (where BWP switching refers to switching from a currently active BWP to a not currently active BWP) may be performed independently in paired spectra. In unpaired spectra, downlink and uplink BWP switching may be performed simultaneously. Switching between configured BWPs may occur based on RRC signaling, DCI, expiration of a BWP inactivity timer, and / or an initiation of random access.

[0127] FIG. 9 illustrates an example of bandwidth adaptation using three configured BWPs for an NR carrier. A UE configured with the three BWPs may switch from one BWP to another BWP at a switching point. In the example illustrated in FIG. 9, the BWPs include: a BWP 902 with a bandwidth of 40 MHz and a subcarrier spacing of 15 kHz; a BWP 904 with a bandwidth of 10 MHz and a subcarrier spacing of 15 kHz; and a BWP 906 with a bandwidth of 20 MHz and a subcarrier spacing of 60 kHz. The BWP 902 may be an initial active BWP, and the BWP 904 may be a default BWP. The UE may switch between BWPs at switching points. In the example of FIG. 9, the UE may switch from the BWP 902 to the BWP 904 at aDocket No.: 24-1257PCT switching point 908. The switching at the switching point 908 may occur for any suitable reason, for example, in response to an expiry of a BWP inactivity timer (indicating switching to the default BWP) and / or in response to receiving a DCI indicating BWP 904 as the active BWP. The UE may switch at a switching point 910 from active BWP 904 to BWP 906 in response to receiving a DCI indicating BWP 906 as the active BWP. The UE may switch at a switching point 912 from active BWP 906 to BWP 904 in response to an expiry of a BWP inactivity timer and / or in response to receiving a DCI indicating BWP 904 as the active BWP. The UE may switch at a switching point 914 from active BWP 904 to BWP 902 in response to receiving a DCI indicating BWP 902 as the active BWP.

[0128] If a UE is configured for a secondary cell with a default downlink BWP in a set of configured downlink BWPs and a timer value, UE procedures for switching BWPs on a secondary cell may be the same / similar as those on a primary cell. For example, the UE may use the timer value and the default downlink BWP for the secondary cell in the same / similar manner as the UE would use these values for a primary cell.

[0129] To provide for greater data rates, two or more carriers can be aggregated and simultaneously transmitted to / from the same UE using carrier aggregation (CA). The aggregated carriers in CA may be referred to as component carriers (CCs). When CA is used, there are a number of serving cells for the UE, one for a CC. The CCs may have three configurations in the frequency domain.

[0130] FIG. 10A illustrates the three CA configurations with two CCs. In the intraband, contiguous configuration 1002, the two CCs are aggregated in the same frequency band (frequency band A) and are located directly adjacent to each other within the frequency band. In the intraband, non-contiguous configuration 1004, the two CCs are aggregated in the same frequency band (frequency band A) and are separated in the frequency band by a gap. In the interband configuration 1006, the two CCs are located in frequency bands (frequency band A and frequency band B).

[0131] In an example, up to 32 CCs may be aggregated. The aggregated CCs may have the same or different bandwidths, subcarrier spacing, and / or duplexing schemes (TDD or FDD). A serving cell for a UE using CA may have a downlink CC. For FDD, one or more uplink CCs may be optionally configured for a serving cell. The ability to aggregate more downlink carriers than uplink carriers may be useful, for example, when the UE has more data traffic in the downlink than in the uplink.

[0132] When CA is used, one of the aggregated cells for a UE may be referred to as a primary cell (PCell). The PCell may be the serving cell that the UE initially connects to at RRC connection establishment, reestablishment, and / or handover. The PCell may provide the UE with NAS mobility information and the security input. UEs may have different PCells. In the downlink, the carrier corresponding to the PCell may be referred to as the downlink primary CC (DL PCC). In the uplink, the carrier corresponding to the PCell may be referred to as the uplink primary CC (UL PCC). The otherDocket No.: 24-1257PCT aggregated cells for the UE may be referred to as secondary cells (SCells). In an example, the SCells may be configured after the PCell is configured for the UE. For example, an SCell may be configured through an RRC Connection Reconfiguration procedure. In the downlink, the carrier corresponding to an SCell may be referred to as a downlink secondary CC (DL SCC). In the uplink, the carrier corresponding to the SCell may be referred to as the uplink secondary CC (UL SCC).

[0133] Configured SCells for a UE may be activated and deactivated based on, for example, traffic and channel conditions. Deactivation of an SCell may mean that PDCCH and PDSCH reception on the SCell is stopped and PUSCH, SRS, and CQI transmissions on the SCell are stopped. Configured SCells may be activated and deactivated using a MAC CE with respect to FIG. 4B. For example, a MAC CE may use a bitmap (e.g., one bit per SCell) to indicate which SCells (e.g., in a subset of configured SCells) for the UE are activated or deactivated. Configured SCells may be deactivated in response to an expiration of an SCell deactivation timer (e.g., one SCell deactivation timer per SCell).

[0134] Downlink control information, such as scheduling assignments and scheduling grants, for a cell may be transmitted on the cell corresponding to the assignments and grants, which is known as selfscheduling. The DCI for the cell may be transmitted on another cell, which is known as cross-carrier scheduling. Uplink control information (e.g., HARQ acknowledgments and channel state feedback, such as CQI, PMI, and / or Rl) for aggregated cells may be transmitted on the PUCCH of the PCell. For a larger number of aggregated downlink CCs, the PUCCH of the PCell may become overloaded. Cells may be divided into multiple PUCCH groups.

[0135] FIG. 10B illustrates an example of how aggregated cells may be configured into one or more PUCCH groups. A PUCCH group 1010 and a PUCCH group 1050 may include one or more downlink CCs, respectively. In the example of FIG. 10B, the PUCCH group 1010 includes three downlink CCs: a PCell 1011 , an SCell 1012, and an SCell 1013. The PUCCH group 1050 includes three downlink CCs in the present example: a PCell 1051 , an SCell 1052, and an SCell 1053. One or more uplink CCs may be configured as a PCell 1021 , an SCell 1022, and an SCell 1023. One or more other uplink CCs may be configured as a primary SCell (PSCell) 1061 , an SCell 1062, and an SCell 1063. Uplink control information (UCI) related to the downlink CCs of the PUCCH group 1010, shown as UC1 1031 , UC1 1032, and UCI 1033, may be transmitted in the uplink of the PCell 1021 . Uplink control information (UCI) related to the downlink CCs of the PUCCH group 1050, shown as UCI 1071 , UC1 1072, and UCI 1073, may be transmitted in the uplink of the PSCell 1061 . In an example, if the aggregated cells depicted in FIG. 10B were not divided into the PUCCH group 1010 and the PUCCH group 1050, a single uplink PCell to transmit UCI relating to the downlink CCs, and the PCell may become overloaded. By dividing transmissions of UCI between the PCell 1021 and the PSCell 1061 , overloading may be prevented.Docket No.: 24-1257PCT

[0136] A cell, comprising a downlink carrier and optionally an uplink carrier, may be assigned with a physical cell ID and a cell index. The physical cell ID or the cell index may identify a downlink carrier and / or an uplink carrier of the cell, for example, depending on the context in which the physical cell ID is used. A physical cell ID may be determined using a synchronization signal transmitted on a downlink component carrier. A cell index may be determined using RRC messages. In the disclosure, a physical cell ID may be referred to as a carrier ID, and a cell index may be referred to as a carrier index. For example, when the disclosure refers to a first physical cell ID for a first downlink carrier, the disclosure may mean the first physical cell ID is for a cell comprising the first downlink carrier. The same / similar concept may apply to, for example, a carrier activation. When the disclosure indicates that a first carrier is activated, the specification may mean that a cell comprising the first carrier is activated

[0137] In CA, a multi-carrier nature of a PHY may be exposed to a MAC. In an example, a HARQ entity may operate on a serving cell. A transport block may be generated per assignment / grant per serving cell. A transport block and potential HARQ retransmissions of the transport block may be mapped to a serving cell.

[0138] In the downlink, a base station may transmit (e.g., unicast, multicast, and / or broadcast) one or more Reference Signals (RSs) to a UE (e.g., PSS, SSS, CSI-RS, DMRS, and / or PT-RS, as shown in FIG. 5A). In the uplink, the UE may transmit one or more RSs to the base station (e.g., DMRS, PT-RS, and / or SRS, as shown in FIG. 5B). The PSS and the SSS may be transmitted by the base station and used by the UE to synchronize the UE to the base station. The PSS and the SSS may be provided in a synchronization signal (SS) / physical broadcast channel (PBCH) block that includes the PSS, the SSS, and the PBCH. The base station may periodically transmit a burst of SS / PBCH blocks.

[0139] FIG. 11A illustrates an example of an SS / PBCH block's structure and location. A burst of SS / PBCH blocks may include one or more SS / PBCH blocks (e.g., 4 SS / PBCH blocks, as shown in FIG. 11A). Bursts may be transmitted periodically (e g., every 2 frames or 20 ms). A burst may be restricted to a half-frame (e.g., a first half-frame having a duration of 5 ms). It will be understood that FIG. 11A is an example, and that these parameters (number of SS / PBCH blocks per burst, periodicity of bursts, position of burst within the frame) may be configured based on, for example: a carrier frequency of a cell in which the SS / PBCH block is transmitted; a numerology or subcarrier spacing of the cell; a configuration by the network (e.g., using RRC signaling); or any other suitable factor. In an example, the UE may assume a subcarrier spacing for the SS / PBCH block based on the carrier frequency being monitored, unless the radio network configured the UE to assume a different subcarrier spacing.

[0140] The SS / PBCH block may span one or more OFDM symbols in the time domain (e.g., 4 OFDM symbols, as shown in the example of FIG. 11 A) and may span one or more subcarriers in the frequency domain (e.g., 240 contiguous subcarriers). The PSS, the SSS, and the PBCH may have a common centerDocket No.: 24-1257PCT frequency. The PSS may be transmitted first and may span, for example, 1 OFDM symbol and 127 subcarriers. The SSS may be transmitted after the PSS (e.g., two symbols later) and may span 1 OFDM symbol and 127 subcarriers. The PBCH may be transmitted after the PSS (e.g., across the next 3 OFDM symbols) and may span 240 subcarriers.

[0141] The location of the SS / PBCH block in the time and frequency domains may not be known to the UE (e.g., if the UE is searching for the cell). To find and select the cell, the UE may monitor a carrier for the PSS. For example, the UE may monitor a frequency location within the carrier. If the PSS is not found after a certain duration (e.g., 20 ms), the UE may search for the PSS at a different frequency location within the carrier, as indicated by a synchronization raster. If the PSS is found at a location in the time and frequency domains, the UE may determine, based on a known structure of the SS / PBCH block, the locations of the SSS and the PBCH, respectively. The SS / PBCH block may be a cell-defining SS block (CD-SSB). In an example, a primary cell may be associated with a CD-SSB. The CD-SSB may be located on a synchronization raster. In an example, a cell selection / search and / or reselection may be based on the CD- SSB.

[0142] The SS / PBCH block may be used by the UE to determine one or more parameters of the cell. For example, the UE may determine a physical cell identifier (PCI) of the cell based on the sequences of the PSS and the SSS, respectively. The UE may determine a location of a frame boundary of the cell based on the location of the SS / PBCH block. For example, the SS / PBCH block may indicate that it has been transmitted in accordance with a transmission pattern, wherein a SS / PBCH block in the transmission pattern is a known distance from the frame boundary.

[0143] The PBCH may use a QPSK modulation and may use forward error correction (FEC). The FEC may use polar coding. One or more symbols spanned by the PBCH may carry one or more DMRSs for demodulation of the PBCH. The PBCH may include an indication of a current system frame number (SFN) of the cell and / or a SS / PBCH block timing index. These parameters may facilitate time synchronization of the UE to the base station. The PBCH may include a master information block (MIB) used to provide the UE with one or more parameters. The MIB may be used by the UE to locate remaining minimum system information (RMSI) associated with the cell. The RMSI may include a System Information Block Type 1 (SIB1). The SIB1 may contain information needed by the UE to access the cell. The UE may use one or more parameters of the MIB to monitor PDCCH, which may be used to schedule PDSCH. The PDSCH may include the SIB1 . The SIB1 may be decoded using parameters provided in the MIB. The PBCH may indicate an absence of SIB1 . Based on the PBCH indicating the absence of SIB1 , the UE may be pointed to a frequency. The UE may search for an SS / PBCH block at the frequency to which the UE is pointed.

[0144] The UE may assume that one or more SS / PBCH blocks transmitted with a same SS / PBCH block index are quasi co-located (QCLed) (e.g., having the same / similar Doppler spread, Doppler shift, averageDocket No.: 24-1257PCT gain, average delay, and / or spatial Rx parameters). The UE may not assume QCL for SS / PBCH block transmissions having different SS / PBCH block indices.

[0145] SS / PBCH blocks (e.g., those within a half-frame) may be transmitted in spatial directions (e.g., using different beams that span a coverage area of the cell). In an example, a first SS / PBCH block may be transmitted in a first spatial direction using a first beam, and a second SS / PBCH block may be transmitted in a second spatial direction using a second beam.

[0146] In an example, within a frequency span of a carrier, a base station may transmit a plurality of SS / PBCH blocks. In an example, a first PCI of a first SS / PBCH block of the plurality of SS / PBCH blocks may be different from a second PCI of a second SS / PBCH block of the plurality of SS / PBCH blocks. The PCIs of SS / PBCH blocks transmitted in different frequency locations may be different or the same.

[0147] The CSI-RS may be transmitted by the base station and used by the UE to acquire channel state information (CSI). The base station may configure the UE with one or more CSI-RSs for channel estimation or any other suitable purpose. The base station may configure a UE with one or more of the same / similar CSI-RSs. The UE may measure the one or more CSI-RSs. The UE may estimate a downlink channel state and / or generate a CSI report based on the measuring of the one or more downlink CSI-RSs. The UE may provide the CSI report to the base station. The base station may use feedback provided by the UE (e.g., the estimated downlink channel state) to perform link adaptation.

[0148] The base station may semi-statically configure the UE with one or more CSI-RS resource sets. A CSI-RS resource may be associated with a location in the time and frequency domains and a periodicity. The base station may selectively activate and / or deactivate a CSI-RS resource. The base station may indicate to the UE that a CSI-RS resource in the CSI-RS resource set is activated and / or deactivated.

[0149] The base station may configure the UE to report CSI measurements. The base station may configure the UE to provide CSI reports periodically, aperiodically, or semi-persistently. For periodic CSI reporting, the UE may be configured with a timing and / or periodicity of a plurality of CSI reports. For aperiodic CSI reporting, the base station may request a CSI report. For example, the base station may command the UE to measure a configured CSI-RS resource and provide a CSI report relating to the measurements. For semi-persistent CSI reporting, the base station may configure the UE to transmit periodically, and selectively activate or deactivate the periodic reporting. The base station may configure the UE with a CSI-RS resource set and CSI reports using RRC signaling.

[0150] The CSI-RS configuration may comprise one or more parameters indicating, for example, up to 32 antenna ports. The UE may be configured to employ the same OFDM symbols for a downlink CSI-RS and a control resource set (CORESET) when the downlink CSI-RS and CORESET are spatially QCLed and resource elements associated with the downlink CSI-RS are outside of the physical resource blocks (PRBs) configured for the CORESET. The UE may be configured to employ the same OFDM symbols for downlinkDocket No.: 24-1257PCTCSI-RS and SS / PBCH blocks when the downlink CSI-RS and SS / PBCH blocks are spatially QCLed and resource elements associated with the downlink CSI-RS are outside of PRBs configured for the SS / PBCH blocks.

[0151] Downlink DMRSs may be transmitted by a base station and used by a UE for channel estimation. For example, the downlink DMRS may be used for coherent demodulation of one or more downlink physical channels (e.g. , PDSCH). An NR network may support one or more variable and / or configurable DMRS patterns for data demodulation. At least one downlink DMRS configuration may support a front- loaded DMRS pattern. A front-loaded DMRS may be mapped over one or more OFDM symbols (e.g., one or two adjacent OFDM symbols). A base station may semi-statically configure the UE with a number (e.g., a maximum number) of front-loaded DMRS symbols for PDSCH. A DMRS configuration may support one or more DMRS ports. For example, for single user-MIMO, a DMRS configuration may support up to eight orthogonal downlink DMRS ports per UE. For multiuser-MIMO, a DMRS configuration may support up to 4 orthogonal downlink DMRS ports per UE. A radio network may support (e.g., at least for CP-OFDM) a common DMRS structure for downlink and uplink, wherein a DMRS location, a DMRS pattern, and / or a scrambling sequence may be the same or different. The base station may transmit a downlink DMRS and a corresponding PDSCH using the same precoding matrix. The UE may use the one or more downlink DMRSs for coherent demodulation / channel estimation of the PDSCH.

[0152] In an example, a transmitter (e.g., a base station) may use a precoder matrices for a part of a transmission bandwidth. For example, the transmitter may use a first precoder matrix for a first bandwidth and a second precoder matrix for a second bandwidth. The first precoder matrix and the second precoder matrix may be different based on the first bandwidth being different from the second bandwidth. The UE may assume that a same precoding matrix is used across a set of PRBs. The set of PRBs may be denoted as a precoding resource block group (PRG).

[0153] A PDSCH may comprise one or more layers. The UE may assume that at least one symbol with DMRS is present on a layer of the one or more layers of the PDSCH. A higher layer may configure up to 3 DMRSs for the PDSCH.

[0154] Downlink PT-RS may be transmitted by a base station and used by a UE for phase-noise compensation. Whether a downlink PT-RS is present or not may depend on an RRC configuration The presence and / or pattern of the downlink PT-RS may be configured on a UE-specific basis using a combination of RRC signaling and / or an association with one or more parameters employed for other purposes (e.g., modulation and coding scheme (MCS)), which may be indicated by DCI. When configured, a dynamic presence of a downlink PT-RS may be associated with one or more DCI parameters comprising at least MCS. An NR network may support a plurality of PT-RS densities defined in the time and / or frequency domains. When present, a frequency domain density may be associated with at least oneDocket No.: 24-1257PCT configuration of a scheduled bandwidth. The UE may assume a same precoding for a DMRS port and a PT-RS port. A number of PT-RS ports may be fewer than a number of DMRS ports in a scheduled resource. Downlink PT-RS may be confined in the scheduled time / frequency duration for the UE. Downlink PT-RS may be transmitted on symbols to facilitate phase tracking at the receiver.

[0155] The UE may transmit an uplink DMRS to a base station for channel estimation. For example, the base station may use the uplink DMRS for coherent demodulation of one or more uplink physical channels. For example, the UE may transmit an uplink DMRS with a PUSCH and / or a PUCCH. The uplink DM-RS may span a range of frequencies that is similar to a range of frequencies associated with the corresponding physical channel. The base station may configure the UE with one or more uplink DMRS configurations. At least one DMRS configuration may support a front-loaded DMRS pattern. The front-loaded DMRS may be mapped over one or more OFDM symbols (e.g., one or two adjacent OFDM symbols). One or more uplink DMRSs may be configured to transmit at one or more symbols of a PUSCH and / or a PUCCH. The base station may semi-statically configure the UE with a number (e.g., maximum number) of front-loaded DMRS symbols for the PUSCH and / or the PUCCH, which the UE may use to schedule a single-symbol DMRS and / or a double-symbol DMRS. An NR network may support (e.g., for cyclic prefix orthogonal frequency division multiplexing (CP-OFDM)) a common DMRS structure for downlink and uplink, wherein a DMRS location, a DMRS pattern, and / or a scrambling sequence for the DMRS may be the same or different.

[0156] A PUSCH may comprise one or more layers, and the UE may transmit at least one symbol with DMRS present on a layer of the one or more layers of the PUSCH. In an example, a higher layer may configure up to three DMRSs for the PUSCH.

[0157] Uplink PT-RS (which may be used by a base station for phase tracking and / or phase-noise compensation) may or may not be present depending on an RRC configuration of the UE. The presence and / or pattern of uplink PT-RS may be configured on a UE-specific basis by a combination of RRC signaling and / or one or more parameters employed for other purposes (e.g., Modulation and Coding Scheme (MCS)), which may be indicated by DCI. When configured, a dynamic presence of uplink PT-RS may be associated with one or more DCI parameters comprising at least MCS. A radio network may support a plurality of uplink PT-RS densities defined in time / frequency domain. When present, a frequency domain density may be associated with at least one configuration of a scheduled bandwidth The UE may assume a same precoding for a DMRS port and a PT-RS port. A number of PT-RS ports may be fewer than a number of DMRS ports in a scheduled resource. For example, uplink PT-RS may be confined in the scheduled time / frequency duration for the UE.

[0158] SRS may be transmitted by a UE to a base station for channel state estimation to support uplink channel dependent scheduling and / or link adaptation SRS transmitted by the UE may allow a base station to estimate an uplink channel state at one or more frequencies. A scheduler at the base station mayDocket No.: 24-1257PCT employ the estimated uplink channel state to assign one or more resource blocks for an uplink PUSCH transmission from the UE. The base station may semi-statically configure the UE with one or more SRS resource sets. For an SRS resource set, the base station may configure the UE with one or more SRS resources. An SRS resource set applicability may be configured by a higher layer (e.g., RRC) parameter. For example, when a higher layer parameter indicates beam management, an SRS resource in an SRS resource set of the one or more SRS resource sets (e.g., with the same / similar time domain behavior, periodic, aperiodic, and / or the like) may be transmitted at a time instant (e.g., simultaneously). The UE may transmit one or more SRS resources in SRS resource sets. An NR network may support aperiodic, periodic and / or semi-persistent SRS transmissions. The UE may transmit SRS resources based on one or more trigger types, wherein the one or more trigger types may comprise higher layer signaling (e.g., RRC) and / or one or more DCI formats. In an example, at least one DCI format may be employed for the UE to select at least one of one or more configured SRS resource sets. An SRS trigger type 0 may refer to an SRS triggered based on a higher layer signaling. An SRS trigger type 1 may refer to an SRS triggered based on one or more DCI formats. In an example, when PUSCH and SRS are transmitted in a same slot, the UE may be configured to transmit SRS after a transmission of a PUSCH and a corresponding uplink DMRS.

[0159] The base station may semi-statically configure the UE with one or more SRS configuration parameters indicating at least one of following: a SRS resource configuration identifier; a number of SRS ports; time domain behavior of an SRS resource configuration (e.g., an indication of periodic, semi- persistent, or aperiodic SRS); slot, mini-slot, and / or subframe level periodicity; offset for a periodic and / or an aperiodic SRS resource; a number of OFDM symbols in an SRS resource; a starting OFDM symbol of an SRS resource; an SRS bandwidth; a frequency hopping bandwidth; a cyclic shift; and / or an SRS sequence ID.

[0160] An antenna port is defined such that the channel over which a symbol on the antenna port is conveyed can be inferred from the channel over which another symbol on the same antenna port is conveyed. If a first symbol and a second symbol are transmitted on the same antenna port, the receiver may infer the channel (e.g., fading gain, multipath delay, and / or the like) for conveying the second symbol on the antenna port, from the channel for conveying the first symbol on the antenna port. A first antenna port and a second antenna port may be referred to as quasi co-located (QCLed) if one or more large-scale properties of the channel over which a first symbol on the first antenna port is conveyed may be inferred from the channel over which a second symbol on a second antenna port is conveyed. The one or more large-scale properties may comprise at least one of: a delay spread; a Doppler spread; a Doppler shift; an average gain; an average delay; and / or spatial Receiving (Rx) parameters.

[0161] Channels that use beamforming require beam management. Beam management may comprise beam measurement, beam selection, and beam indication. A beam may be associated with one or moreDocket No.: 24-1257PCT reference signals. For example, a beam may be identified by one or more beamformed reference signals. The UE may perform downlink beam measurement based on downlink reference signals (e.g., a channel state information reference signal (CSI-RS)) and generate a beam measurement report. The UE may perform the downlink beam measurement procedure after an RRC connection is set up with a base station.

[0162] FIG. 11 B illustrates an example of channel state information reference signals (CSI-RSs) that are mapped in the time and frequency domains. A square shown in FIG. 11B may span a resource block (RB) within a bandwidth of a cell. A base station may transmit one or more RRC messages comprising CSI-RS resource configuration parameters indicating one or more CSI-RSs. One or more of the following parameters may be configured by higher layer signaling (e.g., RRC and / or MAC signaling) for a CSI-RS resource configuration: a CSI-RS resource configuration identity, a number of CSI-RS ports, a CSI-RS configuration (e.g., symbol and resource element (RE) locations in a subframe), a CSI-RS subframe configuration (e.g., subframe location, offset, and periodicity in a radio frame), a CSI-RS power parameter, a CSI-RS sequence parameter, a code division multiplexing (CDM) type parameter, a frequency density, a transmission comb, quasi co-location (QCL) parameters (e.g., QCL-scramblingidentity, crs-portscount, mbsfn-subframeconfiglist, csi-rs-configZPid, qcl-csi-rs-configNZPid), and / or other radio resource parameters.

[0163] The three beams illustrated in FIG. 11 B may be configured for a UE in a UE-specific configuration. Three beams are illustrated in FIG. 11 B (beam #1 , beam #2, and beam #3), more or fewer beams may be configured. Beam #1 may be allocated with CSI-RS 1101 that may be transmitted in one or more subcarriers in an RB of a first symbol. Beam #2 may be allocated with CSI-RS 1102 that may be transmitted in one or more subcarriers in an RB of a second symbol. Beam #3 may be allocated with CSI- RS 1103 that may be transmitted in one or more subcarriers in an RB of a third symbol. By using frequency division multiplexing (FDM), a base station may use other subcarriers in a same RB (for example, those that are not used to transmit CSI-RS 1101) to transmit another CSI-RS associated with a beam for another UE. By using time domain multiplexing (TDM), beams used for the UE may be configured such that beams for the UE use symbols from beams of other UEs.

[0164] CSI-RSs such as those illustrated in FIG. 11 B (e.g., CSI-RS 1101 , 1102, 1103) may be transmitted by the base station and used by the UE for one or more measurements. For example, the UE may measure a reference signal received power (RSRP) of configured CSI-RS resources. The base station may configure the UE with a reporting configuration and the UE may report the RSRP measurements to a network (for example, via one or more base stations) based on the reporting configuration. In an example, the base station may determine, based on the reported measurement results, one or more transmission configuration indication (TCI) states comprising a number of reference signals. In an example, the base station may indicate one or more TCI states to the UE (e.g., via RRC signaling, a MAC CE, and / or a DCI).Docket No.: 24-1257PCTThe UE may receive a downlink transmission with a receive (Rx) beam determined based on the one or more TCI states. In an example, the UE may or may not have a capability of beam correspondence. If the UE has the capability of beam correspondence, the UE may determine a spatial domain filter of a transmit (Tx) beam based on a spatial domain filter of the corresponding Rx beam. If the UE does not have the capability of beam correspondence, the UE may perform an uplink beam selection procedure to determine the spatial domain filter of the Tx beam. The UE may perform the uplink beam selection procedure based on one or more sounding reference signal (SRS) resources configured to the UE by the base station. The base station may select and indicate uplink beams for the UE based on measurements of the one or more SRS resources transmitted by the UE.

[0165] In a beam management procedure, a UE may assess (e.g., measure) a channel quality of one or more beam pair links, a beam pair link comprising a transmitting beam transmitted by a base station and a receiving beam received by the UE. Based on the assessment, the UE may transmit a beam measurement report indicating one or more beam pair quality parameters comprising, e.g., one or more beam identifications (e.g., a beam index, a reference signal index, or the like), RSRP, a precoding matrix indicator (PMI), a channel quality indicator (CQI), and / or a rank indicator (Rl).

[0166] FIG. 12A illustrates examples of three downlink beam management procedures: P1 , P2, and P3. Procedure P1 may enable a UE measurement on transmit (Tx) beams of a transmission reception point (TRP) (or multiple TRPs), e.g., to support a selection of one or more base station Tx beams and / or UE Rx beams (shown as ovals in the top row and bottom row, respectively, of P1). Beamforming at a TRP may comprise a Tx beam sweep for a set of beams (shown, in the top rows of P1 and P2, as ovals rotated in a counterclockwise direction indicated by the dashed arrow). Beamforming at a UE may comprise an Rx beam sweep for a set of beams (shown, in the bottom rows of P1 and P3, as ovals rotated in a clockwise direction indicated by the dashed arrow). Procedure P2 may be used to enable a UE measurement on Tx beams of a TRP (shown, in the top row of P2, as ovals rotated in a counterclockwise direction indicated by the dashed arrow). The UE and / or the base station may perform procedure P2 using a smaller set of beams than is used in procedure P1 , or using narrower beams than the beams 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 an Rx beam at the UE.

[0167] FIG. 12B illustrates examples of three uplink beam management procedures: U1 , U2, and U3. Procedure U1 may be used to enable a base station to perform a measurement on Tx beams of a UE, e.g., to support a selection of one or more UE Tx beams and / or base station Rx beams (shown as ovals in the top row and bottom row, respectively, of U1). Beamforming at the UE may include, e.g., a Tx beam sweep from a set of beams (shown in the bottom rows of U1 and U3 as ovals rotated in a clockwise direction indicated by the dashed arrow). Beamforming at the base station may include, e.g., an Rx beam sweepDocket No.: 24-1257PCT from a set of beams (shown, in the top rows of U1 and U2, as ovals rotated in a counterclockwise direction indicated by the dashed arrow). Procedure U2 may be used to enable the base station to adjust its Rx beam when the UE uses a fixed Tx beam. The UE and / or the base station may perform procedure U2 using a smaller set of beams than is used in procedure P1 , or using narrower beams than the beams used in procedure P1 . This may be referred to as beam refinement The UE may perform procedure U3 to adjust its Tx beam when the base station uses a fixed Rx beam.

[0168] A UE may initiate a beam failure recovery (BFR) procedure based on detecting a beam failure. The UE may transmit a BFR request (e.g., a preamble, a UCI, an SR, a MAC CE, and / or the like) based on the initiating of the BFR procedure. The UE may detect the beam failure based on a determination that a quality of beam pair link(s) of an associated control channel is unsatisfactory (e.g , having an error rate higher than an error rate threshold, a received signal power lower than a received signal power threshold, an expiration of a timer, and / or the like).

[0169] The UE may measure a quality of a beam pair link using one or more reference signals (RSs) comprising one or more SS / PBCH blocks, one or more CSI-RS resources, and / or one or more demodulation reference signals (DMRSs). A quality of the beam pair link may be based on one or more of a block error rate (BLER), an RSRP value, a signal to interference plus noise ratio (SINR) value, a reference signal received quality (RSRQ) value, and / or a CSI value measured on RS resources. The base station may indicate that an RS resource is quasi co-located (QCLed) with one or more DM-RSs of a channel (e.g., a control channel, a shared data channel, and / or the like). The RS resource and the one or more DMRSs of the channel may be QCLed when the channel characteristics (e.g., Doppler shift, Doppler spread, average delay, delay spread, spatial Rx parameter, fading, and / or the like) from a transmission via the RS resource to the UE are similar or the same as the channel characteristics from a transmission via the channel to the UE.

[0170] A network (e g., a gNB and / or an ng-eNB of a network) and / or the UE may initiate a random access procedure. A UE in an RRCJDLE state and / or an RRCJNACTIVE state may initiate the random access procedure to request a connection setup to a network. The UE may initiate the random access procedure from an RRC_CONNECTED state. The UE may initiate the random access procedure to request uplink resources (e.g , for uplink transmission of an SR when there is no PUCCH resource available) and / or acquire uplink timing (e.g., when uplink synchronization status is non-synchronized). The UE may initiate the random access procedure to request one or more system information blocks (SIBs) (e.g., other system information such as SIB2, SIB3, and / or the like). The UE may initiate the random access procedure for a beam failure recovery request. A network may initiate a random access procedure for a handover and / or for establishing time alignment for an SCell addition.Docket No.: 24-1257PCT

[0171] FIG. 13A illustrates a four-step contention-based random access procedure. Prior to initiation of the procedure, a base station may transmit a configuration message 1310 to the UE. The procedure illustrated in FIG. 13A comprises transmission of four messages: a Msg 1 1311, a Msg 2 1312, a Msg 3 1313, and a Msg 4 1314. The Msg 1 1311 may include and / or be referred to as a preamble (or a random access preamble). The Msg 2 1312 may include and / or be referred to as a random access response (RAR).

[0172] The configuration message 1310 may be transmitted, for example, using one or more RRC messages. The 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 comprise at least one of 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 a UE in an RRC_CONNECTED state and / or in an RRCJNACTIVE state). The UE may determine, based on the one or more RACH parameters, a time-frequency resource and / or an uplink transmit power for transmission of the Msg 1 1311 and / or the Msg 3 1313. Based on the one or more RACH parameters, the UE may determine a reception timing and a downlink channel for receiving the Msg 2 1312 and the Msg 4 1314.

[0173] The one or more RACH parameters provided in the configuration message 1310 may indicate one or more Physical RACH (PRACH) occasions available for transmission of the Msg 1 1311. The one or more PRACH occasions may be predefined. The one or more RACH parameters may indicate one or more available sets of one or more PRACH occasions (e.g., prach-Con fig Index). The one or more RACH parameters may indicate an association between (a) one or more PRACH occasions 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-RSs. For example, the one or more RACH parameters may indicate a number of SS / PBCH blocks mapped to a PRACH occasion and / or a number of preambles mapped to a SS / PBCH blocks.

[0174] The one or more RACH parameters provided in the configuration message 1310 may be used to determine an uplink transmit power of Msg 1 1311 and / or Msg 3 1313. For example, the one or more RACH parameters may indicate a reference power for a preamble transmission (e.g., a received target power and / or an initial power of the preamble transmission). There may be one or more power offsets indicated by the one or more RACH parameters. For example, the one or more RACH parameters may indicate: a power ramping step; a power offset between SSB and CSI-RS; a power offset between transmissions of the Msg 1 1311 and the Msg 3 1313; and / or a power offset value between preamble groups. The one or more RACH parameters may indicate one or more thresholds based on which the UEDocket No.: 24-1257PCT may determine at least one reference signal (e.g., an SSB and / or CSI-RS) and / or an uplink carrier (e.g., a normal uplink (NUL) carrier and / or a supplemental uplink (SUL) carrier).

[0175] The Msg 1 1311 may include one or more preamble transmissions (e.g., a preamble transmission and one or more preamble retransmissions). An RRC message may be used to configure one or more preamble groups (e.g., group A and / or group B). A preamble group may comprise one or more preambles. The UE may determine the preamble group based on a pathloss measurement and / or a size of the Msg 3 1313. The UE may measure an RSRP of one or more reference signals (e.g., SSBs and / or CSI-RSs) and determine at least one reference signal having an RSRP above an RSRP threshold (e.g., rsrp- ThresholdSSB and / or rsrp-ThresholdCSi-RS). The UE may select at least one preamble associated with the one or more reference signals and / or a selected preamble group, for example, if the association between the one or more preambles and the at least one reference signal is configured by an RRC message.

[0176] The UE may determine the preamble based on the one or more RACH parameters provided in the configuration message 1310. For example, the UE may determine the preamble based on a pathloss measurement, an RSRP measurement, and / or a size of the Msg 3 1313. As another example, the one or more RACH parameters may indicate: a preamble format; a 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). A base station may use the one or more RACH parameters to configure the UE with an association between one or more preambles and one or more reference signals (e.g., SSBs and / or CSI-RSs). If the association is configured, the UE may determine the preamble to include in Msg 1 1311 based on the association. The Msg 1 1311 may be transmitted to the base station via one or more PRACH occasions. The UE may use one or more reference signals (e.g., SSBs and / or CSI-RSs) for selection of the preamble and for determining of the PRACH occasion. One or more RACH parameters (e.g., ra-ssb-OccasionMsklndex and / or ra-OccasionList) may indicate an association between the PRACH occasions and the one or more reference signals.

[0177] The UE may perform a preamble retransmission if no response is received following a preamble transmission. The UE may increase an uplink transmit power for the preamble retransmission. The UE may select an initial preamble transmit power based on a pathloss measurement and / or a target received preamble power configured by the network. The UE may determine to retransmit a preamble and may ramp up the uplink transmit power. The UE may receive one or more RACH parameters (e.g., PREAMBLE_POWER_RAMPING_STEP) indicating a ramping step for the preamble retransmission. The ramping step may be an amount of incremental increase in uplink transmit power for a retransmission. The UE may ramp up the uplink transmit power if the UE determines a reference signal (e g., SSB and / or CSI- RS) that is the same as a previous preamble transmission. The UE may count a number of preambleDocket No.: 24-1257PCT transmissions and / or retransmissions (e.g., PREAMBLE_TRANSMISSION_COUNTER). The UE may determine that a random access procedure completed unsuccessfully, for example, if the number of preamble transmissions exceeds a threshold configured by the one or more RACH parameters (e.g., preambleTransMax) .

[0178] The Msg 2 1312 received by the UE may include an RAR. In some scenarios, the Msg 2 1312 may include multiple RARs corresponding to multiple UEs. The Msg 2 1312 may be received after or in response to the transmitting of the Msg 1 1311. The Msg 2 1312 may be scheduled on the DL-SCH and indicated on a PDCCH using a random access RNTI (RA-RNTI). The Msg 2 1312 may indicate that the Msg 1 1311 was received by the base station. The Msg 2 1312 may include a time-alignment command that may be used by the UE to adjust the UE’s transmission timing, a scheduling grant for transmission of the Msg 3 1313, and / or a Temporary Cell RNTI (TC-RNTI). After transmitting a preamble, the UE may start a time window (e.g., ra-ResponseWindow) to monitor a PDCCH for the Msg 2 1312. The UE may determine when to start the time window based on a PRACH occasion that the UE uses to transmit the preamble. For example, the UE may start the time window one or more symbols after a last symbol of the preamble (e.g., at a first PDCCH occasion from an end of a preamble transmission). The one or more symbols may be determined based on a numerology. The PDCCH may be in a common search space (e.g., a Typel-PDCCH common search space) configured by an RRC message. The UE may identify the RAR based on a Radio Network Temporary Identifier (RNTI). RNTIs may be used depending on one or more events initiating the random access procedure. The UE may use random access RNTI (RA-RNTI). The RA-RNTI may be associated with PRACH occasions in which the UE transmits a preamble. For example, the UE may determine the RA-RNTI based on: an OFDM symbol index; a slot index; a frequency domain index; and / or a UL carrier indicator of the PRACH occasions. An example of RA-RNTI may be as follows:

[0179] RA-RNTI= 1 + s_id + 14 x t_id + 14 x 80 x fjd + 14 x 80 x 8 x ul_carrier_id , where s_id may be an index of a first OFDM symbol of the PRACH occasion (e.g., 0 sjd < 14), t_id may be an index of a first slot of the PRACH occasion in a system frame (e.g., 0 t_id < 80), f_id may be an index of the PRACH occasion in the frequency domain (e.g., 0 < f_id < 8), and ul_carrier_id may be a UL carrier used for a preamble transmission (e.g., 0 for an NUL carrier, and 1 for an SUL carrier).

[0180] The UE may transmit the Msg 3 1313 in response to a successful reception of the Msg 2 1312 (e.g., using resources identified in the Msg 2 1312). The Msg 3 1313 may be used for contention resolution in, for example, the contention-based random access procedure illustrated in FIG. 13A. In some scenarios, a plurality of UEs may transmit a same preamble to a base station and the base station may provide an RAR that corresponds to a UE. Collisions may occur if the plurality of UEs interpret the RAR as corresponding to themselves. Contention resolution (e.g., using the Msg 3 1313 and the Msg 4 1314) mayDocket No.: 24-1257PCT be used to increase the likelihood that the UE does not incorrectly use an identity of another the UE. To perform contention resolution, the UE may include a device identifier in the Msg 3 1313 (e.g ., a C-RNTI if assigned, a TC-RNTI included in the Msg 2 1312, and / or any other suitable identifier).

[0181] The Msg 4 1314 may be received after or in response to the transmitting of the Msg 3 1313. If a C-RNTI was included in the Msg 3 1313, the base station will address the UE on the PDCCH using the C-RNTI. If the UE's unique C-RNTI is detected on the PDCCH, the random access procedure is determined to be successfully completed. If a TC-RNTI is included in the Msg 3 1313 (e.g., if the UE is in an RRCJDLE state or not otherwise connected to the base station), Msg 4 1314 will be received using a DL-SCH associated with the TC-RNTI. If a MAC PDU is successfully decoded and a MAC PDU comprises the UE contention resolution identity MAC CE that matches or otherwise corresponds with the CCCH SDU sent (e.g., transmitted) in Msg 3 1313, the UE may determine that the contention resolution is successful and / or the UE may determine that the random access procedure is successfully completed.

[0182] The UE may be configured with a supplementary uplink (SUL) carrier and a normal uplink (NUL) carrier. An initial access (e.g., random access procedure) may be supported in an uplink carrier. For example, a base station may configure the UE with two separate RACH configurations: one for an SUL carrier and the other for an NUL carrier. For random access in a cell configured with an SUL carrier, the network may indicate which carrier to use (NUL or SUL). The UE may determine the SUL carrier, for example, if a measured quality of one or more reference signals is lower than a broadcast threshold. Uplink transmissions of the random access procedure (e.g., the Msg 1 1311 and / or the Msg 3 1313) may remain on the selected carrier. The UE may switch an uplink carrier during the random access procedure (e.g., between the Msg 1 1311 and the Msg 3 1313) in one or more cases. For example, the UE may determine and / or switch an uplink carrier for the Msg 1 1311 and / or the Msg 3 1313 based on a channel clear assessment (e.g., a listen-before-talk).

[0183] FIG. 13B illustrates a two-step contention-free random access procedure. Similar to the four-step contention-based random access procedure illustrated in FIG. 13A, a base station may, prior to initiation of the procedure, transmit a configuration message 1320 to the UE. The configuration message 1320 may be analogous in some respects to the configuration message 1310. The procedure illustrated in FIG. 13B comprises transmission of two messages: a Msg 1 1321 and a Msg 2 1322. The Msg 1 1321 and the Msg 2 1322 may be analogous in some respects to the Msg 1 1311 and a Msg 2 1312 illustrated in FIG. 13A, respectively. As will be understood from FIGS. 13A and 13B, the contention-free random access procedure may not include messages analogous to the Msg 3 1313 and / or the Msg 4 1314.

[0184] The contention-free random access procedure illustrated in FIG. 13B may be initiated for a beam failure recovery, other SI request, SCell addition, and / or handover. For example, a base station mayDocket No.: 24-1257PCT indicate or assign to the UE the preamble to be used for the Msg 1 1321 The UE may receive, from the base station via PDCCH and / or RRC, an indication of a preamble (e.g., ra-Preamblelndex).

[0185] After transmitting a preamble, the UE may start a time window (e.g., ra-ResponseWindow) to monitor a PDCCH for the RAR. In the event of a beam failure recovery request, the base station may configure the UE with a separate time window and / or a separate PDCCH in a search space indicated by an RRC message (e.g., recoverySearchSpaceld). The UE may monitor for a PDCCH transmission addressed to a Cell RNTI (C-RNTI) on the search space. In the con tent! on -free random access procedure illustrated in FIG. 13B, the UE may determine that a random access procedure successfully completes after or in response to transmission of Msg 1 1321 and reception of a corresponding Msg 2 1322. The UE may determine that a random access procedure successfully completes, for example, if a PDCCH transmission is addressed to a C-RNTI. The UE may determine that a random access procedure successfully completes, for example, if the UE receives an RAR comprising a preamble identifier corresponding to a preamble transmitted by the UE and / or the RAR comprises a MAC sub-PDU with the preamble identifier. The UE may determine the response as an indication of an acknowledgement for an SI request.

[0186] FIG. 13C illustrates another two-step random access procedure. Similar to the random access procedures illustrated in FIGS. 13A and 13B, a base station may, prior to initiation of the procedure, transmit a configuration message 1330 to the UE. The configuration message 1330 may be analogous in some respects to the configuration message 1310 and / or the configuration message 1320. The procedure illustrated in FIG. 13C comprises transmission of two messages: a Msg A 1331 and a Msg B 1332

[0187] Msg A 1331 may be transmitted in an uplink transmission by the UE. Msg A 1331 may comprise one or more transmissions of a preamble 1341 and / or one or more transmissions of a transport block 1342. The transport block 1342 may comprise contents that are similar and / or equivalent to the contents of the Msg 3 1313 illustrated in FIG. 13A. The transport block 1342 may comprise UCI (e.g., an SR, a HARQ ACK / NACK, and / or the like). The UE may receive the Msg B 1332 after or in response to transmitting the Msg A 1331 . The Msg B 1332 may comprise contents that are similar and / or equivalent to the contents of the Msg 2 1312 (e.g., an RAR) illustrated in FIGS. 13A and 13B and / or the Msg 4 1314 illustrated in FIG. 13A.

[0188] The UE may initiate the two-step random access procedure in FIG. 13C for licensed spectrum and / or unlicensed spectrum. The UE may determine, based on one or more factors, whether to initiate the two-step random access procedure. The one or more factors may be: a radio access technology in use (e.g., LTE, NR, and / or the like); whether the UE has valid TA or not; a cell size; the UE’s RRC state; a type of spectrum (e.g., licensed vs. unlicensed); and / or any other suitable factors.

[0189] The UE may determine, based on two-step RACH parameters included in the configuration message 1330, a radio resource and / or an uplink transmit power for the preamble 1341 and / or theDocket No.: 24-1257PCT transport block 1342 included in the Msg A 1331. The RACH parameters may indicate a modulation and coding schemes (MCS), a time-frequency resource, and / or a power control for the preamble 1341 and / or the transport block 1342. A time-frequency resource for transmission of the preamble 1341 (e.g., a PRACH) and a time-frequency resource for transmission of the transport block 1342 (e.g., a PUSCH) may be multiplexed using FDM, TDM, and / or CDM. The RACH parameters may enable the UE to determine a reception timing and a downlink channel for monitoring for and / or receiving Msg B 1332.

[0190] The transport block 1342 may comprise data (e.g., delay-sensitive data), an identifier of the UE, security information, and / or device information (e.g., an International Mobile Subscriber Identity (IMSI)). The base station may transmit the Msg B 1332 as a response to the Msg A 1331 . The Msg B 1332 may comprise at least one of following: a preamble identifier; a timing advance command; a power control command; an uplink grant (e.g., a radio resource assignment and / or an MCS); a UE identifier for contention resolution; and / or an RNTI (e.g., a C-RNTI or a TC-RNTI). The UE may determine that the two-step random access procedure is successfully completed if: a preamble identifier in the Msg B 1332 is matched to a preamble transmitted by the UE; and / or the identifier of the UE in Msg B 1332 is matched to the identifier of the UE in the Msg A 1331 (e.g., the transport block 1342).

[0191] A UE and a base station may 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 comprise downlink control signaling transmitted from the base station to the UE and / or uplink control signaling transmitted from the UE to the base station.

[0192] The downlink control signaling may comprise: a downlink scheduling assignment; an uplink scheduling grant indicating uplink radio resources and / or a transport format; a slot format information; a preemption indication; a power control command; and / or any other suitable signaling. The UE may receive the downlink control signaling in a payload transmitted by the base station on a 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 common PDCCH (GC-PDCCH) that is common to a group of UEs.

[0193] A base station may attach one or more cyclic redundancy check (CRC) parity bits to a DCI in order to facilitate detection of transmission errors. When the DCI is intended for a UE (or a group of the UEs), the base station may scramble the CRC parity bits with an identifier of the UE (or an identifier of the group of the UEs). Scrambling the CRC parity bits with the identifier may comprise Modulo-2 addition (or an exclusive OR operation) of the identifier value and the CRC parity bits. The identifier may comprise a 16-bit value of a radio network temporary identifier (RNTI).

[0194] DCIs may be used for different purposes. A purpose may be indicated by the type of RNTI used to scramble the CRC parity bits. For example, a DCI having CRC parity bits scrambled with a paging RNTI (P-Docket No.: 24-1257PCTRNTI) may indicate paging information and / or a system information change notification. The P-RNTI may be predefined as "FFFE” in hexadecimal. A DCI having CRC parity bits scrambled with a system information RNTI (SI-RNTI) may indicate a broadcast transmission of the system information. The SI-RNTI may be predefined as “FFFF” in hexadecimal. A DCI having CRC parity bits scrambled with a random access RNTI (RA-RNTI) may indicate a random access response (RAR). A DCI having CRC parity bits scrambled with a cell RNTI (C-RNTI) may indicate a dynamically scheduled unicast transmission and / or a triggering of PDCCH-ordered random access. A DCI having CRC parity bits scrambled with a temporary cell RNTI (TC-RNTI) may indicate a contention resolution (e.g., a Msg 3 analogous to the Msg 3 1313 illustrated in FIG. 13A). Other RNTIs configured to the UE by a base station may comprise a Configured Scheduling RNTI (CS-RNTI), a Transmit Power Control-PUCCH RNTI (TPC-PUCCH-RNTI), a Transmit Power Control-PUSCH RNTI (TPC-PUSCH-RNTI), a Transmit Power Control-SRS RNTI (TPC-SRS-RNTI), an Interruption RNTI (INT-RNTI), a Slot Format Indication RNTI (SFI-RNTI), a Semi-Persistent CSI RNTI (SP-CSI-RNTI), a Modulation and Coding Scheme Cell RNTI (MCS-C-RNTI), and / or the like.

[0195] Depending on the purpose and / or content of a DCI, the base station may transmit the DCIs with one or more DCI formats. For example, DCI format 0_0 may be used for scheduling of PUSCH in a cell. DCI format 0_0 may be a fallback DCI format (e.g., with compact DCI payloads). DCI format 0_1 may be used for scheduling of PUSCH in a cell (e.g., with more DCI payloads than DCI format 0_0). DCI format 1_0 may be used for scheduling of PDSCH in a cell. DCI format 1_0 may be a fallback DCI format (e.g., with compact DCI payloads). DCI format 1_1 may be used for scheduling of PDSCH in a cell (e.g., with more DCI payloads than DCI format 1 _0) . DCI format 2_0 may be used for providing a slot format indication to a group of UEs. DCI format 2_1 may be used for notifying a group of UEs of a physical resource block and / or OFDM symbol where the UE may assume no transmission is intended to the UE. DCI format 2_2 may be used for transmission of a transmit power control (TPC) command for PUCCH or PUSCH. DCI format 2_3 may be used for transmission of a group of TPC commands for SRS transmissions by one or more UEs. DCI format(s) for new functions may be defined in future releases. DCI formats may have different DCI sizes, or may share the same DCI size.

[0196] After scrambling a DCI with a RNTI, the base station may process the DCI with channel coding (e.g , polar coding), rate matching, scrambling and / or QPSK modulation. A base station may map the coded and modulated DCI on resource elements used and / or configured for a PDCCH. Based on a payload size of the DCI and / or a coverage of the base station, the base station may transmit the DCI via a PDCCH occupying a number of contiguous control channel elements (CCEs). The number of the contiguous CCEs (referred to as aggregation level) may be 1 , 2, 4, 8, 16, and / or any other suitable number. A CCE may comprise a number (e.g., 6) of resource-element groups (REGs). A REG may comprise a resource block inDocket No.: 24-1257PCT an OFDM symbol. The mapping of the coded and modulated DCI on the resource elements may be based on mapping of CCEs and REGs (e.g., CCE-to-REG mapping).

[0197] FIG. 14A illustrates an example of CORESET configurations for a bandwidth part. The base station may transmit a DCI via a PDCCH on one or more control resource sets (CORESETs). A CORESET may comprise a time-frequency resource in which the UE tries to decode a DCI using one or more search spaces. The base station may configure a CORESET in the time-frequency domain. In the example of FIG. 14A, a first CORESET 1401 and a second CORESET 1402 occur at the first symbol in a slot. The first CORESET 1401 overlaps with the second CORESET 1402 in the frequency domain. A third CORESET 1403 occurs at a third symbol in the slot. A fourth CORESET 1404 occurs at the seventh symbol in the slot. CORESETs may have a different number of resource blocks in frequency domain.

[0198] FIG. 14B illustrates an example of a CCE-to-REG mapping for DCI transmission on a CORESET and PDCCH processing. The CCE-to-REG mapping may be an interleaved mapping (e.g., for the purpose of providing frequency diversity) or a non-interleaved mapping (e.g., for the purposes of facilitating interference coordination and / or frequency-selective transmission of control channels). The base station may perform different or same CCE-to-REG mapping on different CORESETs. A CORESET may be associated with a CCE-to-REG mapping by RRC configuration. A CORESET may be configured with an antenna port quasi co-location (QCL) parameter. The antenna port QCL parameter may indicate QCL information of a demodulation reference signal (DMRS) for PDCCH reception in the CORESET.

[0199] The base station may transmit, to the UE, RRC messages comprising configuration parameters of one or more CORESETs and one or more search space sets. The configuration parameters may indicate an association between a search space set and a CORESET. A search space set may comprise a set of PDCCH candidates formed by CCEs at a given aggregation level. The configuration parameters may indicate: a number of PDCCH candidates to be monitored per aggregation level; a PDCCH monitoring periodicity and a PDCCH monitoring pattern; one or more DCI formats to be monitored by the UE; and / or whether a search space set is a common search space set or a UE-specific search space set. A set of CCEs in the common search space set may be predefined and known to the UE. A set of CCEs in the UE- specific search space set may be configured based on the UE’s identity (e.g., C-RNTI).

[0200] As shown in FIG. 14B, the UE may determine a time-frequency resource for a CORESET based on RRC messages. The UE may determine a CCE-to-REG mapping (e.g., interleaved or non-interleaved, and / or mapping parameters) for the CORESET based on configuration parameters of the CORESET. The UE may determine a number (e.g., at most 10) of search space sets configured on the CORESET based on the RRC messages. The UE may monitor a set of PDCCH candidates according to configuration parameters of a search space set. The UE may monitor a set of PDCCH candidates in one or more CORESETs for detecting one or more DCIs. Monitoring may comprise decoding one or more PDCCHDocket No.: 24-1257PCT candidates of the set of the PDCCH candidates according to the monitored DCI formats. Monitoring may comprise decoding a DCI content of one or more PDCCH candidates with possible (or configured) PDCCH locations, possible (or configured) PDCCH formats (e.g., number of CCEs, number of PDCCH candidates in common search spaces, and / or number of PDCCH candidates in the UE-specific search spaces) and possible (or configured) DCI formats. The decoding may be referred to as blind decoding. The UE may determine a DCI as valid for the UE, in response to CRC checking (e.g., scrambled bits for CRC parity bits of the DCI matching a RNTI value). The UE may process information contained in the DCI (e.g., a scheduling assignment, an uplink grant, power control, a slot format indication, a downlink preemption, and / or the like).

[0201] The UE may transmit uplink control signaling (e.g., uplink control information (UCI)) to a base station. The uplink control signaling may comprise hybrid automatic repeat request (HARQ) acknowledgements for received DL-SCH transport blocks. The UE may transmit the HARQ acknowledgements after receiving a DL-SCH transport block. Uplink control signaling may comprise channel state information (CSI) indicating channel quality of a physical downlink channel. The UE may transmit the CSI to the base station. The base station, based on the received CSI, may determine transmission format parameters (e.g., comprising multi-antenna and beamforming schemes) for a downlink transmission. Uplink control signaling may comprise scheduling requests (SR). The UE may transmit an SR indicating that uplink data is available for transmission to the base station. The UE may transmit a UCI (e.g , HARQ acknowledgements (HARQ-ACK), CSI report, SR, and the like) via a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH). The UE may transmit the uplink control signaling via a PUCCH using one of several PUCCH formats.

[0202] There may be five PUCCH formats and the UE may determine a PUCCH format based on a size of the UCI (e.g., a number of uplink symbols of UCI transmission and a number of UCI bits). PUCCH format 0 may have a length of one or two OFDM symbols and may include two or fewer bits. The UE may transmit UCI in a PUCCH resource using PUCCH format 0 if the transmission is over one or two symbols and the number of HARQ-ACK information bits with positive or negative SR (HARQ-ACK / SR bits) is one or two. PUCCH format 1 may occupy a number between four and fourteen OFDM symbols and may include two or fewer bits. The UE may use PUCCH format 1 if the transmission is four or more symbols and the number of HARQ-ACK / SR bits is one or two. PUCCH format 2 may occupy one or two OFDM symbols and may include more than two bits. The UE may use PUCCH format 2 if the transmission is over one or two symbols and the number of UCI bits is two or more. PUCCH format 3 may occupy a number between four and fourteen OFDM symbols and may include more than two bits. The UE may use PUCCH format 3 if the transmission is four or more symbols, the number of UCI bits is two or more and PUCCH resource does not include an orthogonal cover code. PUCCH format 4 may occupy a number between four and fourteenDocket No.: 24-1257PCTOFDM symbols and may include more than two bits. The UE may use PUCCH format 4 if the transmission is four or more symbols, the number of UCI bits is two or more and the PUCCH resource includes an orthogonal cover code.

[0203] The base station may transmit configuration parameters to the UE for a plurality of PUCCH resource sets using, for example, an RRC message. The plurality of PUCCH resource sets (e.g ., up to four sets) may be configured on an uplink BWP of a cell. A PUCCH resource set may be configured with a PUCCH resource set index, a plurality of PUCCH resources with a PUCCH resource being identified by a PUCCH resource identifier (e.g., pucch-Resourceid) , and / or a number (e.g., a maximum number) of UCI information bits the UE may transmit using one of the plurality of PUCCH resources in the PUCCH resource set When configured with a plurality of PUCCH resource sets, the UE may select one of the plurality of PUCCH resource sets based on a total bit length of the UCI information bits (e.g., HARQ-ACK, SR, and / or CSI). If the total bit length of UCI information bits is two or fewer, the UE may select a first PUCCH resource set having a PUCCH resource set index equal to “0’’. If the total bit length of UCI information bits is greater than two and less than or equal to a first configured value, the UE may select a second PUCCH resource set having a PUCCH resource set index equal to "1”. If the total bit length of UCI information bits is greater than the first configured value and less than or equal to a second configured value, the UE may select a third PUCCH resource set having a PUCCH resource set index equal to “2”. If the total bit length of UCI information bits is greater than the second configured value and less than or equal to a third value (e.g., 1406), the UE may select a fourth PUCCH resource set having a PUCCH resource set index equal to "3”.

[0204] After determining a PUCCH resource set from a plurality of PUCCH resource sets, the UE may determine a PUCCH resource from the PUCCH resource set for UCI (HARQ-ACK, CSI, and / or SR) transmission. The UE may determine the PUCCH resource based on a PUCCH resource indicator in a DCI (e.g , with a DCI format 1_0 or DCI for 1_1) received on a PDCCH. A three-bit PUCCH resource indicator in the DCI may indicate one of eight PUCCH resources in the PUCCH resource set. Based on the PUCCH resource indicator, the UE may transmit the UCI (HARQ-ACK, CSI and / or SR) using a PUCCH resource indicated by the PUCCH resource indicator in the DCI.

[0205] FIG. 15 illustrates an example of a wireless device 1502 in communication with a base station 1504 in accordance with embodiments of the present disclosure. The wireless device 1502 and base station 1504 may be part of a mobile communication network, such as the mobile communication network 100 illustrated in FIG. 1A, the mobile communication network 150 illustrated in FIG. 1 B, or any other communication network. Only one wireless device 1502 and one base station 1504 are illustrated in FIG. 15, but it will be understood that a mobile communication network may include more than one UE and / or more than one base station, with the same or similar configuration as those shown in FIG. 15.Docket No.: 24-1257PCT

[0206] The base station 1504 may connect the wireless device 1502 to a core network (not shown) through radio communications over the air interface (or radio interface) 1506. The communication direction from the base station 1504 to the wireless device 1502 over the air interface 1506 is known as the downlink, and the communication direction from the wireless device 1502 to the base station 1504 over the air interface is known as the uplink. Downlink transmissions may be separated from uplink transmissions using FDD, TDD, and / or some combination of the two duplexing techniques.

[0207] In the downlink, data to be sent to the wireless device 1502 from the base station 1504 may be provided to the processing system 1508 of the base station 1504. The data may be provided to the processing system 1508 by, for example, a core network. In the uplink, data to be sent to the base station 1504 from the wireless device 1502 may be provided to the processing system 1518 of the wireless device 1502. The processing system 1508 and the processing system 1518 may implement layer 3 and layer 2 OSI functionality to process the data for transmission. Layer 2 may include an SDAP layer, a PDCP layer, an RLC layer, and a MAC layer, for example, with respect to FIG. 2A, FIG. 2B, FIG. 3, and FIG. 4A. Layer 3 may include an RRC layer as with respect to FIG. 2B.

[0208] After being processed by processing system 1508, the data to be sent to the wireless device 1502 may be provided to a transmission processing system 1510 of base station 1504. Similarly, after being processed by the processing system 1518, the data to be sent to base station 1504 may be provided to a transmission processing system 1520 of the wireless device 1502. The transmission processing system 1510 and the transmission processing system 1520 may implement layer 1 OSI functionality. Layer 1 may include a PHY layer with respect to FIG. 2A, FIG. 2B, FIG. 3, and FIG. 4A. For transmit processing, the PHY layer may perform, for example, forward error correction coding of transport channels, interleaving, rate matching, mapping of transport channels to physical channels, modulation of physical channel, multiple-input multiple-output (MIMO) or multi-antenna processing, and / or the like.

[0209] At the base station 1504, a reception processing system 1512 may receive the uplink transmission from the wireless device 1502. At the wireless device 1502, a reception processing system 1522 may receive the downlink transmission from base station 1504. The reception processing system 1512 and the reception processing system 1522 may implement layer 1 OSI functionality. Layer 1 may include a PHY layer with respect to FIG. 2A, FIG. 2B, FIG. 3, and FIG. 4A. For receive processing, the PHY layer may perform, for example, error detection, forward error correction decoding, deinterleaving, demapping of transport channels to physical channels, demodulation of physical channels, MIMO or multi-antenna processing, and / or the like.

[0210] As shown in FIG. 15, a wireless device 1502 and the base station 1504 may include multiple antennas. The multiple antennas may 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 / orDocket No.: 24-1257PCT beamforming. In other examples, the wireless device 1502 and / or the base station 1504 may have a single antenna.

[0211] The processing system 1508 and the processing system 1518 may be associated with a memory 1514 and a memory 1524, respectively. Memory 1514 and memory 1524 (e.g., one or more non-transitory computer readable mediums) may store computer program instructions or code that may be executed by the processing system 1508 and / or the processing system 1518 to carry out one or more of the functionalities discussed in the present application. Although not shown in FIG. 15, the transmission processing system 1510, the transmission processing system 1520, the reception processing system 1512, and / or the reception processing system 1522 may be coupled to a memory (e.g., one or more non- transitory computer readable mediums) storing computer program instructions or code that may be executed to carry out one or more of their respective functionalities.

[0212] The processing system 1508 and / or the processing system 1518 may comprise one or more controllers and / or one or more processors. The one or more controllers and / or one or more processors may comprise, 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 device, discrete gate and / or transistor logic, discrete hardware components, an onboard unit, or any combination thereof. The processing system 1508 and / or the processing system 1518 may perform at least one of signal coding / processing, data processing, power control, input / output processing, and / or any other functionality that may enable the wireless device 1502 and the base station 1504 to operate in a wireless environment.

[0213] The processing system 1508 and / or the processing system 1518 may be connected to one or more peripherals 1516 and one or more peripherals 1526, respectively. The one or more peripherals 1516 and the one or more peripherals 1526 may include software and / or hardware that provide features and / or functionalities, for example, a speaker, a microphone, a keypad, a display, a touchpad, a power source, a satellite transceiver, a universal serial bus (USB) port, a hands-free headset, a frequency modulated (FM) radio unit, a media player, an Internet browser, an electronic control unit (e.g., for a motor vehicle), and / or one or more sensors (e.g., an accelerometer, a gyroscope, a temperature sensor, a radar sensor, a lidar sensor, an ultrasonic sensor, a light sensor, a camera, and / or the like). The processing system 1508 and / or the processing system 1518 may receive user input data from and / or provide user output data to the one or more peripherals 1516 and / or the one or more peripherals 1526. The processing system 1518 in the wireless device 1502 may receive power from a power source and / or may be configured to distribute the power to the other components in the wireless device 1502. The power source may comprise one or more sources of power, for example, a battery, a solar cell, a fuel cell, or any combination thereof. The processing system 1508 and / or the processing system 1518 may be connected to a GPS chipset 1517 andDocket No.: 24-1257PCT a GPS chipset 1527, respectively. The GPS chipset 1517 and the GPS chipset 1527 may be configured to provide geographic location information of the wireless device 1502 and the base station 1504, respectively.

[0214] FIG. 16A illustrates an example structure for uplink transmission. A baseband signal representing a physical uplink shared channel may perform one or more functions. The one or more functions may comprise at least one of: scrambling; modulation of scrambled bits to generate complex-valued symbols; mapping of the complex-valued modulation symbols onto one or several transmission layers; transform precoding to generate complex-valued symbols; precoding of the complex-valued symbols; mapping of precoded complex-valued symbols to resource elements; generation of complex-valued time-domain Single Carrier-Frequency Division Multiple Access (SC-FDMA) or CP-OFDM signal for an antenna port; and / or the like. In an example, when transform precoding is enabled, a SC-FDMA signal for uplink transmission may be generated. In an example, when transform precoding is not enabled, a CP-OFDM signal for uplink transmission may be generated by FIG. 16A. These functions are illustrated as examples and it is anticipated that other mechanisms may be implemented in various embodiments.

[0215] FIG. 16B illustrates an example structure for modulation and up-conversion of a baseband signal to a carrier frequency. The baseband signal may be a complex-valued SC-FDMA or CP-OFDM baseband signal for an antenna port and / or a complex-valued Physical Random Access Channel (PRACH) baseband signal. Filtering may be employed prior to transmission.

[0216] FIG. 16C illustrates an example structure for downlink transmissions A baseband signal representing a physical downlink channel may perform one or more functions. The one or more functions may comprise: scrambling of coded bits in a codeword to be transmitted on a physical channel; modulation of scrambled bits to generate complex-valued modulation symbols; mapping of the complex-valued modulation symbols onto one or several transmission layers; precoding of the complex-valued modulation symbols on a layer for transmission on the antenna ports; mapping of complex-valued modulation symbols for an antenna port to resource elements; generation of complex-valued time-domain OFDM signal for an antenna port; and / or the like. These functions are illustrated as examples and it is anticipated that other mechanisms may be implemented in various embodiments.

[0217] FIG. 16D illustrates another example structure for modulation and up-conversion of a baseband signal to a carrier frequency. The baseband signal may be a complex-valued OFDM baseband signal for an antenna port. Filtering may be employed prior to transmission.

[0218] A wireless device may receive from a base station one or more messages (e.g., RRC messages) comprising configuration parameters of a plurality of cells (e.g., primary cell, secondary cell). The wireless device may communicate with at least one base station (e.g., two or more base stations in dual connectivity) via the plurality of cells. The one or more messages (e.g., as a part of the configurationDocket No.: 24-1257PCT parameters) may comprise parameters of physical, MAC, RLC, PCDP, SDAP, RRC layers for configuring the wireless device. For example, the configuration parameters may comprise parameters for configuring physical and MAC layer channels, bearers, etc. For example, the configuration parameters may comprise parameters indicating values of timers for physical, MAC, RLC, PCDP, SDAP, RRC layers, and / or communication channels.

[0219] A timer may begin running once it is started and continue running until it is stopped or until it expires. A timer may be started if it is not running or restarted if it is running. A timer may be associated with a value (e.g., the timer may be started or restarted from a value or may be started from zero and expire once it reaches the value). The duration of a timer may not be updated until the timer is stopped or expires (e.g., due to BWP switching). A timer may be used to measure a time period / window for a process. When the specification refers to an implementation and procedure related to one or more timers, it will be understood that there are multiple ways to implement the one or more timers. For example, it will be understood that one or more of the multiple ways to implement a timer may be used to measure a time period / window for the procedure. For example, a random access response window timer may be used for measuring a window of time for receiving a random access response. In an example, instead of starting and expiry (or expiration) of a random access response window timer, the time difference between two time stamps may be used. When a timer is restarted, a process for measurement of time window may be restarted. Other example implementations may be provided to restart a measurement of a time window.

[0220] Layer - 1 and / or layer - 2 triggered mobility (LTM) may be referred to as lower layer triggered mobility. LTM is a procedure in which a base station (e.g., gNB, cell, network, CU, DU, source DU, candidate or target DU, source CU, candidate CU, gNB-DU, gNB-CU, and the like) may receive one or more layer 1 and / or 2 (L-1 / 2), e.g., physical layer, medium access control (MAC) layer, lower layer, and the like, measurement reports from wireless devices. Based on (or on the basis of receiving) the one or more L-1 / 2 measurement reports (the one or more L-1 / 2 measurement reports may be referred to as one or more (L-1 / 2) measurements), the base station may switch (e.g., change, swap, move, handover) a wireless device's serving cell(s) via (e.g., through or using) a control command (e.g., medium access control (MAC) control element (CE), L-1 / 2 control command, DCI, PDCCH, cell switch MAC CE, LTM command MAC CE, LTM cell switch command MAC CE, and the like).

[0221] In some aspects, LTM and conditional LTM (C-LTM) may be used interchangeably.

[0222] The base station may prepare (e.g., indicate to the wireless device) one or more candidate / target cells, e.g., for LTM.

[0223] In some aspects, the one or more candidate / target cells may be referred to as one or more candidate cells for LTM (or one or more candidate / target cells for LTM, or one or more candidate / target LTM cells, or one or more LTM candidate / target cells, one or more candidate / target cell for a mobilityDocket No.: 24-1257PCT procedure (e.g., LTM and / or a conditional mobility procedure), one or more candidate target cells, and / or the like). The one or more candidate / target cells may comprise one or more serving cells. The one or more candidate / target cells may comprise one or more (candidate / target) non-serving cells. The one or more candidate / target cells may comprise one or more (candidate / target) SCells. The one or more candidate / target cells may comprise one or more (candidate / target) activated SCells. The one or more candidate / target cells may comprise one or more (candidate / target) deactivated SCells.

[0224] In some aspects, a candidate / target cell, of the one or more candidate / target cells, may be referred to as an LTM candidate / target cell (or a candidate cell for LTM, or candidate / target cell for LTM, or candidate / target LTM cell, or LTM candidate / target cell, and the like).

[0225] In some aspects, “LTM” and “LTM procedure” may be used interchangeably.

[0226] The base station may provide, e.g., for LTM, one or more candidate / target (LTM cell) configurations to the wireless device through or via one or more messages (e.g., one or more RRC messages). The one or more messages may comprise one or more configuration parameters (e.g., one or more RRC configuration parameters). The one or more messages and / or the one or more configuration parameters may comprise the one or more candidate / target (LTM cell) configurations.

[0227] The one or more messages may indicate the one or more candidate / target cells. The one or more candidate / target (LTM) cell configurations may be for / indicate / associated with / of the one or more candidate / target cells. Each candidate / target (LTM) cell configuration, of the one or more candidate / target (LTM cell) configurations, may be for / indicate / associated with a respective candidate / target cell of the one or more candidate / target cells. Then (e.g., after the wireless device receives the one or more messages) an LTM cell switch may be triggered (e.g., by the base station / g NB), by selecting one candidate / target (LTM cell) configuration, of the one or more candidate / target (LTM cell) configurations, as a target (LTM cell) configuration for LTM by the base station. The one or more candidate / target (LTM cell) configurations may be added by the network / base station via RRC signaling (e.g., via / using one or more second messages). The one or more candidate / target (LTM cell) configurations may be modified / updated / changed by the network / base station via RRC signaling (e.g., via / using one or more second messages). The one or more candidate / target (LTM cell) configurations may be released by the network / base station via RRC signaling (e.g , via / using one or more second messages).

[0228] In an example, the one or more candidate / target (LTM cell) configurations may be / comprise / be comprised in one or more RRCReconfigurations (messages). Each RRCReconfiguration of the one or more RRCReconfigurations may be for / associated with a respective candidate / target cell of the one or more candidate / target cells. In an example, the one or more candidate / target (LTM cell) configurations may be / comprise / be comprised in one or more CellGroupConfig information elements (lEs). EachDocket No.: 24-1257PCTCellGroupConfig IE of the one or more CellGroupConfig lEs may be for / associated with a respective candidate / target cell of the one or more candidate / target cells.

[0229] In LTM (e.g., LTM procedure, LTM process, and the like), the one or more candidate / target (LTM cell) configurations may be provided (e.g., transmitted by the base station to the wireless device via one or more second messages) as one or more delta configurations on top of one or more reference configurations. The one or more reference configurations may be managed separately, e.g., by the base station. The wireless device may store the one or more reference configurations as separate configuration(s), each.

[0230] In LTM, user plane may be continued whenever possible (e.g., intra-DU LTM, intra-DU mobility, intra-DU handover, and the like), without reset, with a target to avoid data loss and additional delay of data recovery. Security may not be updated in LTM. Subsequent LTM between candidate / target cell(s), of the one or more candidate / target cells, may be performed by the wireless device / base station without RRC reconfiguration. For example, the wireless device may not release candidate / target (LTM cell) configuration(s), of the one or more candidate / target (LTM cell) configurations, after LTM is triggered / completed.

[0231] LTM may support / comprise intra-gN B-distributed unit (DU) mobility (e.g., intra-DU mobility). LTM may support / comprise intra-gN B-central / centralized unit (CU) mobility (e.g., intra-CU mobility). LTM may support / comprise inter-g N B-DU mobility (e.g., inter-DU mobility). LTM may support / comprise inter-g N B-CU mobility (e g., inter-CU mobility). LTM may support / comprise inter-frequency mobility, including / comprising mobility to inter-frequency cell that is not a current serving cell.

[0232] LTM may support / comprise PCell change in non-carrier aggregation (CA) scenario. For example, a source / serving cell may be a PCell. A candidate / target cell may not be a PCell. The wireless device may cell switch (e.g., cell switch via LTM, cell switch command MAC CE, LTM command MAC CE, and the like) to a candidate / target cell (e.g., of the one or more candidate / target cells) After the cell switch, the candidate / target cell may be the PCell. The source / serving cell may not be the PCell after the cell switch.

[0233] LTM may support / comprise PCell change without SCell change in CA scenario.

[0234] LTM may support / comprise PCell change with SCell changes(s) in CA scenario. For example, a target candidate / target cell (e.g., target PCell / target SCell(s)) may not be a current serving cell (CA-to-CA scenario with PCell change). For example, the target PCell may be a current SCell. For example, the target SCell may be a current PCell.

[0235] The source / serving cell may be a PCell, SCell, PSCell, SpCell, and / or the like. Each candidate / target cell, of the one or more candidate / target cells, may be a PCell, SCell, activated SCell, deactivated SCell, PSCell, SpCell, non-serving cell, unlicensed cell, cell operating with shared spectrum channel access, FR1 cell, FR2 cell, and / or the like.Docket No.: 24-1257PCT

[0236] LTM may support / comprise dual connectivity (DC) scenario, at least for the PSCell change without master node (MN) involvement case, e.g., intra-secondary node (SN).

[0237] Cell switch trigger information for LTM may be conveyed (e.g., by / from the base station to the wireless device) in a control command (e.g., MAC CE, activation command, cell switch command, cell switch MAC CE, cell switch command MAC CE, LTM command MAC CE, LTM cell switch command MAC CE, DCI, PDCCH order, and the like). The control command may comprise 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 a candidate / target (LTM cell) configuration) from / among / of the one or more candidate / target cells (and / or one or more candidate / target (LTM cell) configurations). Cell-specific, radio bearer, and / or measurement configurations may be part of a / each candidate / target (LTM cell) configuration of the one or more candidate / target (LTM cell) configurations.

[0238] The control command may indicate TCI state(s) (and / or other beam information, e.g., reference signal, quasi colocation (QCL) assumption, spatial filter, spatial domain filter, spatial domain transmission filter, spatial domain reception filter, transmit beam, reception beam, and the like) to activate for the target / candidate cell(s).

[0239] SCell activation / deactivation (amongst SCells associated with the one or more candidate / target (cell) configurations) may be performed (e.g., by the wireless device and / or the base station) simultaneously with / using / via the control command (e.g., LTM triggering MAC CE, cell-switch MAC CE, cell switch command, cell switch command / indication, LTM command MAC CE, control command, and the like).

[0240] The wireless device may perform contention based random access (CBRA) and / or contention free random access (CFRA) at / after cell switch (e.g., after receiving the control command, e.g., cell-switch MAC CE). The wireless device may skip random access (RA) procedure (e.g., the CBRA and / or the CFRA) if the wireless device does not need to acquire TA for the target / candidate cell during / after cell switch (e g., in response to the wireless device determining TA of the target / candidate cell before / prior to receiving the control command). RACH resources for CFRA may be provided by the base station in one or more configuration parameters (or via the one or more candidate / target (LTM cell) configurations) and / or the control command.

[0241] In an example, the control command may indicate / provide CFRA resources. The wireless device may perform CFRA in / via the candidate / target cell using the CFRA resources.

[0242] FIG. 17 shows procedure(s) and / or steps for or of LTM. Subsequent LTM may be done or performed (e.g., by the base station and / or the wireless device) by repeating early synchronization and / or early uplink (UL) synchronization (e.g., early sync 1716), LTM execution 1726, and / or LTM completionDocket No.: 24-1257PCT1724 steps or procedures (as shown in FIG. 17) without releasing other candidates (e.g., the one or more candidate / target (LTM cell) configurations) after each LTM completion.

[0243] In the example of FIG. 17, a wireless device 1702 may transmit one or more measurement reports (e.g., measurement report(s) 1704). The one or more measurement reports may be, for example, one or more layer 3 (L3) measurement reports. Wireless device 1702 may transmit the one or more (L3) measurement reports to or via a base station or gNB. Wireless device 1702 may transmit the one or more (L3) measurement reports via a cell 1706. Cell 1706 may be, for example, a serving or source cell. The base station may serve (e.g., be, comprise, of, for, and / or associated with) cell 1706. Cell 1706 may be a PCell, SpCell, PSCell, SCell, and / or any other serving cell.

[0244] Wireless device 1702 may be in an RRC connected mode. Wireless device 1702 may be in an RRC connected mode during or while performing the LTM procedure.

[0245] In some aspects, wireless device 1702 may be in an RRC connected mode when or while performing any of the embodiments described in the present disclosure.

[0246] In some aspects, wireless device 1702 may be in an RRC inactive mode when or while performing any of the embodiments described in the present disclosure.

[0247] In some aspects, wireless device 1702 may be in an RRC idle mode when or while performing any of the embodiments described in the present disclosure.

[0248] The base station may determine to determine (e.g., use or perform) LTM, for example, based on the one or more (L3) measurement reports. The base station may initiate LTM candidate preparation (e.g., LTM prep. 1708 and / or LTM candidate preparation 1710), for example, by coordinating with one or more candidate / target cells (e.g., one or more (gNB-)DUs, one or more source or serving (gNB-)DUs, one or more candidate / target (gNB)DUs, one or more (gNB-)CUs, one or more candidate / target (gNB-)CUs, and the like). The one or more candidate / target cells may comprise a cell 1712. In an example, the one or more candidate / target cells may comprise cell 1706. In an example, cell 1712 may be a non-serving cell

[0249] In some aspects, cell 1712 may be the same as cell 1706.

[0250] The base station may transmit one or more messages (e.g., RRC messages) to the wireless device 1702. The one or more messages may comprise one or more candidate / target (LTM) cell configurations e.g., for LTM / LTM procedure(s). The one or more candidate / target (LTM) cell configurations are indicated as configuration(s) 1714 in FIG. 17.

[0251] The one or more messages may comprise one or more configuration parameters indicating or comprising configuration(s) 1714. Configuration(s) 1714 may be, comprise, or be comprised in one or more RRCReconfiguration (parameters / messages), e.g., the one or more messages. Configuration(s) 1714 may comprise one or more LTM-Config information elements.Docket No.: 24-1257PCT

[0252] Wireless device 1702 may receive, from or via the base station (e.g., via cell 1706), a respective candidate / target (LTM cell) configuration, of configuration(s) 1714, for each candidate / target cell of the one or more candidate / target cells. Wireless device 1702 may store configuration(s) 1714 of the one or more candidate / target cells.

[0253] Wireless device 1702 may transmit RRCReconfigurationComplete message(s) to the base station (e.g., via cell 1706), for example, based on (or after) receiving and / or storing configuration(s) 1714.

[0254] Wireless device 1702 may perform an early sync 1716. Early sync 1716 may be referred to as, for example, early uplink synchronization or early uplink synchronization procedure.

[0255] Early sync 1716 may comprise, for example, early downlink synchronization. Early sync 1716 may be referred to as “early” synchronization (e.g , early sync 1716 may use the term “ear / y”) based on wireless device 1702 performing early sync 1716 before (e.g., earlier than) switching to a candidate / target cell (e.g., cell 1712).

[0256] Early sync 1716 may comprise DL synchronization via (e.g., to, with, for, of, associated with) candidate / target cell(s) of the one or more candidate / target cells (e.g., indicated in or by configuration(s) 1714). Wireless device 1702 may perform DL synchronization via (e.g., to, with, for, of, associated with) the candidate / target cell(s) before receiving a control command (e.g., a control command 1718, cell switch MAC CE, LTM command MAC CE), for example, based on or using one or more reference signals (e.g., based on measuring the one or more reference signals (e.g., SSB, CSI-RS, CRS, RSs 1720, and the like), wherein each reference signal (RS), of the one or more RSs (e.g., RSs 1720), is associated with (e.g., for, from, via, of) a respective candidate / target cell of the one or more candidate / target cells). The one or more RSs (e.g., RSs 1720) may comprise one or more SSBs, one or more CRSs, one or more CSI-RSs, one or more SRSs, one or more tracking RSs, one or more positioning RSs, and / or a combination thereof.

[0257] Wireless device 1702 may perform timing advance (TA) acquisition (e.g., using an RA procedure by transmitting an RA preamble, or without an RA procedure, e.g., based on wireless device / UE-based TA measurements, and the like). Early sync 1716 may comprise the TA acquisition (e.g., may be referred to as early TA acquisition (ETA)). The TA acquisition / ETA may be referred to as, for example, (early) uplink (UL) synchronization. Wireless device 1702 may perform the TA acquisition / ETA (e.g., acquire TA(s) of (e.g., for, of, associated with) candidate / target cell(s) of the one or more candidate / target cells). Wireless device 1702 may perform the TA acquisition / ETA, for example, before receiving control command 1718. The candidate / target cell(s) may comprise cell 1712.

[0258] As shown in FIG. 17, wireless device 1702 may receive control command 1718. Control command 1718 may be, for example, an LTM cell switch command MAC CE. Control command 1718 may be referred to as, for example, cell switch MAC CE, LTM cell switch MAC CE, LTM command MAC CE, and / or the like. Control command 1718 may trigger (e.g., initiate, instruct, or indicate wireless device 1702 to perform) aDocket No.: 24-1257PCT cell switch (e.g., a PCell or SpCell switch or change) from a first cell (e.g., cell 1706) to a second cell (e.g., cell 1712). For example, the control command 1718 may indicate (e.g., initiate or trigger) a change or switch of a PCell or SpCell from the cell 1706 to the cell 1712. For example, prior to receiving control command 1718, cell 1706 may be a PCell or SpCell (e.g., for wireless device 1702). After (e.g., upon or at) receiving control command 1718, cell 1712 may be the PCell or SpCell (e.g., for wireless device 1702).After (e.g., upon or at) receiving control command 1718, cell 1706 may not be the PCell or SpCell (e.g., for wireless device 1702) anymore.

[0259] Wireless device 1702 may acquire the TA(s) using an RA procedure. Wireless device 1702 may receive a downlink signal initiating or triggering the RA procedure. The downlink signal may be or comprise a downlink control information (DCI) The downlink signal may be referred to as a PDCCH order. The downlink signal may be or comprise a MAC CE (e.g., control command 1718). The downlink signal may indicate an RA preamble (e.g., RACH transmission, PRACH transmission, preamble, Msg 1, Msg A, and / or any other name indicating a message of an RA procedure) for the RA procedure. The RA procedure may be of (e.g., via, for, associated with) cell 1712 (or a different candidate / target cell of the one or more candidate / target cells). Wireless device 1702 may receive the downlink signal via cell 1706.

[0260] For Dual Connectivity operation the term SpCell may refer to PCell of an MCG or PSCell of an SCG depending on if wireless device 1702 is associated to the MCG or the SCG, respectively. Otherwise, the term SpCell may refer to PCell. An SpCell may support PUCCH transmission and contention-based Random Access, and may always be activated.

[0261] In some aspects, transmitting or receiving signals via a cell may be the same as or be referred to as transmitting or receiving the signals from, in, on, to, for, toward, towards, associated with, corresponding to, and / or configured for the cell.

[0262] In some aspects, the term "signal” may be replaced by “message,” "channel,” and / or “transmission.”

[0263] Wireless device 1702 may perform L-1 / 2 measurements (e.g., of one or more RSs) on each or any candidate / target cell of the one or more candidate / target cells. Wireless device 1702 may transmit L-1 / 2 (e.g., lower-layer, physical layer, MAC layer, and the like) measurement report(s) 1722 to the base station (e.g , via cell 1706). Wireless device 1702 may determine L-1 / 2 measurement report(s) 1722 based on measuring one or more RSs from or associated with the one or more candidate / target cells, wherein at least one RS of the one or more RSs is from or associated with a respective candidate / target cell of the one or more candidate / target cells.

[0264] The base station or gNB may determine to execute LTM cell switch to a candidate / target cell, of the one or more candidate / target cells, for wireless device 1702, for example, based on (receiving) the L- 1 / 2 measurement report(s) 1722. The base station may transmit (e.g., via cell 1706) control command 1718Docket No.: 24-1257PCT triggering cell switch (e g., LTM cell switch, cell switch for LTM, PCell switch or change, cell switch procedure, handover, and / or the like) to wireless device 1702.

[0265] Control command 1718 may be referred to as handover command or an RRC message comprising reconfiguration-with-sync.

[0266] Control command 1718 may comprise a candidate / target (LTM cell) configuration index. The candidate / target (LTM cell) configuration index may indicate or identify a candidate / target (LTM cell) configuration, of configuration(s) 1714, that is associated with (e.g., of or for) the candidate / target cell (e.g., cell 1712). The candidate / target (LTM cell) configuration index (and / or the candidate / target (LTM cell) configuration) may indicate or identify the candidate / target cell (e.g., cell 1712) of the one or more candidate / target cells. Wireless device 1702 may switch to (e.g., apply or use) the candidate / target (LTM cell) configuration of the (LTM) candidate / target cell indicated in control command 1718.

[0267] Wireless device 1702 may perform an RA procedure via or in the candidate / target cell (e.g., if a TA for / of the candidate / target cell is not available or valid at wireless device 1702).

[0268] Wireless device 1702 may indicate, for example, via the candidate / target cell (e.g., the base station or gNB), of a successful completion of (LTM) cell switch towards the candidate / target cell. Wireless device 1702 may transmit one or more uplink (UL) messages to indicate an LTM completion 1724. LTM completion 1724 may comprise a successful completion of (LTM) cell switch towards the candidate / target cell (e.g., cell 1712). LTM completion 1724 may comprise an RRC reconfiguration complete message transmission (e.g., by wireless device 1702 via cell 1712), an RRC setup complete message transmission, and the like. LTM completion 1724 may comprise an RRC message transmission.

[0269] Although the present disclosure may refer to an LTM (or LTM procedure), this procedure may alternatively be referred to / indicate as a cell switch procedure triggered by a control command / cell switch command (e.g., MAC CE, Layer 1 / 2 command / message, and the like) or as Layer 1 / 2 triggered mobility, MAC CE triggered cell switch procedure, non-handover, non-handover mobility, non-handover reconfiguration with sync, non-reconfiguration with sync mobility, handover, reconfiguration with sync, and / or the like. In some aspects, LTM may refer to a conditional LTM (e.g., an LTM procedure that is triggered based on one or more conditions being fulfilled without receiving a cell switch command like control command 1718).

[0270] FIG. 18 shows an example timing diagram of a UE-based TA measurement procedure as per an aspect of an embodiment of the present disclosure. Early sync 1716 may, for example, be or comprise the UE-based TA measurement procedure. In the example of FIG. 18, a wireless device 1802 may receive a control command 1804.

[0271] Wireless device 1802 may be the same as wireless device 1702.Docket No.: 24-1257PCT

[0272] Wireless device 1802 may receive a control command 1804. Control command 1804 may be or comprise, for example, a TA command MAC CE, an absolute TA command MAC CE, a random access response, a Msg2 PDSCH / PDCCH indicating RAR / Msg2, a MsgB (e.g., Message B or a second message of a two-step random access procedure), and / or a different MAC CE.

[0273] In an example, wireless device 1802 may receive configuration(s) 1714 before or prior to receiving control command 1804. In another example, wireless device 1802 may receive configuration(s) 1714 after receiving control command 1804. In an example, wireless device 1802 may receive configuration(s) 1714 together or along with receiving control command 1804. In an example, configuration(s) 1714 may comprise control command 1804.

[0274] In an example, control command 1804 comprises a TA command 1806. TA command 1806 may be or comprise a TA command field. TA command 1806 may, for example, indicate an index value TA (0, 1 , 2... 63) used to control an amount of timing adjustment that wireless device 1802 applies. A length of TA command 1806 in control command 1804 may be, for example, 6 bits. In another example, a length of TA command 1806 in control command 1804 may be, for example, 12 bits.

[0275] In an example, control command 1804 may comprise a TA group (TAG) identity field. The TAG identity field may indicate a TAG Identity of an addressed TAG. The TAG comprising the SpCell may have a TAG Identity 0. The length of the TAG identity field may be 2 bits.

[0276] Wireless device 1802 may receive control command 1804 via a cell 1808. The addressed TAG may comprise cell 1808. Cell 1808 may be a serving or source cell. Cell 1808 may be, for example, cell 1706. Cell 1808 may be a SpCell (e.g., PCell or a PSCell). Cell 1808 may be an SCell.

[0277] Wireless device 1802 may, when control command 1804 is received, and if an NTA has been maintained with the addressed TAG (e.g., TAG identified or indicated in the TAG identity field), apply TA command 1806, comprised in control command 1804, for the addressed / indicated TAG. Wireless device 1802 may, when control command 1804 is received, and if an NTA has been maintained with the indicated or addressed TAG (e.g., in the TAG identity field), start or restart a time alignment timer associated with the indicated or addressed TAG.

[0278] Wireless device 1802 may receive control command 1804 from a first base station. Wireless device 1802 may receive control command 1804 via cell 1808. The first base station may serve (e.g., be of, for, associated with) cell 1808.

[0279] TA command 1806 may indicate a first TA value of a TAG. The TAG may, for example, comprise cell 1808. Wireless device 1802 may determine a first TA value of the TAG based on TA command 1806. Wireless device 1802 may determine the first TA of the TAG, for example, based on receiving control command 1804. Wireless device 1802 may determine the first TA associated with (e.g., of or for) the TAG, for example, based on receiving TA command 1806.Docket No.: 24-1257PCT

[0280] In the example of FIG. 18, wireless device 1802 may receive a control command 1810. Wireless device 1802 may receive control command 1810 from the first base station. Wireless device 1802 may receive control command 1810, for example, via cell 1808. Control command 1810 may be, for example, a UE-based TA measurement procedure activation / deactivation MAC-CE.

[0281] Control command 1810 may indicate (e.g., trigger or initiate) a UE-based TA measurement procedure. Wireless device 1802 may begin (e.g., start, trigger, or initiate) a UE-based TA measurement procedure, for example, based on, in response to, or upon receiving control command 1810. In an example, control command 1810 may comprise or be control command 1718.

[0282] In an example, wireless device 1802 may not receive control command 1810. Wireless device 1802 may begin (e g., start, trigger, or initiate) a UE-based TA measurement procedure, for example, without receiving control command 1810.

[0283] The UE-based TA measurement procedure may be referred to as, for example, UE-based TA measurement, UE-based TA measurement process, autonomous TA measurement by the wireless device, UE-based TA acquisition, TA determination without a TA command, UE-measured TA (process or procedure), cell switch procedure, and / or the like

[0284] The UE-based TA measurement procedure may comprise or be a method (e.g., procedure or process) performed (e.g., used or done) by wireless device 1802 to determine a second TA value of (e.g., for or associated with) a cell 1812 in an open-loop manner (e.g., without receiving a TA command associated with the second TA and / or the cell 1812). Cell 1812 may be a candidate / target cell of the one or more candidate / target cells.

[0285] Cell 1812 may be, for example, cell 1712.

[0286] The UE-based TA measurement procedure may comprise or be a method (e.g., procedure or process) performed (e.g., used or done) by wireless device 1802 to determine or measure a TA value (e.g., the second TA value) of (e.g., for or associated with) a TAG comprising a cell (e.g., cell 1812) in an openloop manner (e.g., without receiving a TA command associated with the TA and / or the cell).

[0287] In an example, cell 1812 may not be a candidate / target (LTM) cell. In an example, cell 1812 may not be associated with LTM.

[0288] In an example, the one or more candidate / target cells may comprise cell 1812. For example, configuration(s) 1714 may comprise a first candidate / target (LTM cell) configuration associated with cell 1812. The first candidate / target (LTM cell) configuration may comprise a first parameter. The first parameter may be, for example, enable-UE-TA. The first parameter may be, for example, UE-measure-TA- ID. The first parameter may indicate to wireless device 1802 whether wireless device 1802 is allowed or enabled to determine or measure a TA (value) of cell 1812 using or based on a UE-based TA measurement procedure.Docket No.: 24-1257PCT

[0289] In some aspects, the terms “parameter” and “field” may be used interchangeably and may mean the same.

[0290] In an example, the first parameter may be set to a first value (e.g., enable, true, yes, 1, 0, 2, 3, 4, and the like). The first parameter may indicate that wireless device 1802 is allowed or enabled to measure a TA (value) of cell 1812 using or based on a UE-based TA measurement procedure (or a UE-based TA measurement is enabled for cell 1812) based on the first parameter being set to the first value (e.g., matching an identity of a serving cell, e.g., cell 1808). In an example, a presence or absence of the first parameter (e.g., in configuration(s) 1714) may indicate that wireless device 1802 is allowed or enabled to measure a TA (value) of cell 1812 using or based on a UE-based TA measurement procedure (or a UE- based TA measurement is enabled for cell 1812)

[0291] In an example, the first parameter may be set to a second value (e.g., disable, false, no, 1 , 0, 3, 4 and the like). The first parameter may indicate that wireless device 1802 is not allowed or enabled to determine a TA value of cell 1812 using or based on a UE-based TA measurement procedure (or a UE- based TA measurement is not enabled (or disabled) for cell 1812) based on the first parameter being set to the second value (e.g., not matching to the serving cell, e g., cell 1808). In another example, a presence or absence of the first parameter (e.g., in configuration(s) 1714) may indicate that wireless device 1802 is not allowed or enabled to determine a TA value of cell 1812 using or based on a UE-based TA measurement procedure (or a UE-based TA measurement is not enabled (or disabled) for cell 1812).

[0292] In an example, configuration(s) 1714 may comprise a second parameter. The second parameter may be, for example, Itm-ServingCellUE-MeasuredTA-ID. The second parameter may indicate to wireless device 1802 whether UE-based TA measurements may be performed towards an LTM candidate cell.

[0293] The first parameter may be, for example, Itm-UE-MeasuredTA-ID. The first parameter may indicate to wireless device 1802 whether UE-based TA measurements may be performed towards an LTM candidate cell.

[0294] In an example, a first value (e.g., 0, 1 , 2, ...) of the first parameter may be the same as a second value (e.g., 0, 1 , 2, ...) of the second parameter. Configuration(s) 1714 may indicate to the wireless device 1802 to perform the UE-based TA measurement, for example, based on the first value (e.g., 0, 1 , 2, ...) of the first parameter being the same as the second value (e.g., 0, 1 , 2, ...) of the second parameter. Wireless device 1802 may perform the UE-based TA measurement (e.g., as shown in FIG. 18), for example, based on the first value of the first parameter being the same as the second value of the second parameter. Configuration(s) 1714 may indicate that wireless device 1802 is configured with UE-based TA measurements, for example, based on the first value of the first parameter being the same as the second value of the second parameter.Docket No.: 24-1257PCT

[0295] In an example, the first value of the first parameter may not be the same as (e.g., may be different from) the second value of the second parameter. Configuration(s) 1714 may indicate to wireless device 1802 not to perform the UE-based TA measurement (or configuration(s) 1714 may not indicate to wireless device 1802 to perform the UE-based TA measurement), for example, based on the first value (e.g., 0, 1 , 2, ...) of the first parameter being different from (e.g., not the same as) the second value (e.g., 0, 1 , 2, ...) of the second parameter. Wireless device 1802 may not perform the UE-based TA measurement (e.g., may perform a random access procedure / RACH-procedure based ETA, or may not perform the early synchronization), for example, based on the first value of the first parameter being different from (e.g., not the same as) the second value of the second parameter. Configuration(s) 1714 may indicate that wireless device 1802 is not configured with UE-based TA measurements, for example, based on the first value of the first parameter being different from the second value of the second parameter.

[0296] Wireless device 1802 may determine (e.g., initiate, trigger, start, or begin) a UE-based TA measurement procedure (e.g., to determine a second TA value of / for / associated with cell 1812), for example, based on: the first parameter and / or the second parameter indicating that wireless device 1802 is allowed (e g., enabled or configured) to determine a TA value of cell 1812 using or based on a UE-based TA measurement procedure (or a UE-based TA measurement is enabled / configured for cell 1812), the second control command triggering (e.g., indicating or initiating) a UE-based TA measurement procedure, and / or wireless device 1802 being capable of determining the second TA of cell 1812 based on a UE- based TA measurement procedure.

[0297] In an example, wireless device 1802 may transmit a capability message to the first base station (e.g., via cell 1808). The capability message may indicate whether wireless device 1802 is capable of (or can support or supports) determining the second TA of an LTM candidate cell (e.g., cell 1812) using or based on a UE-based TA measurement procedure.

[0298] In the example of FIG. 18, wireless device 1802 determines the second TA associated with (e.g., of or for) cell 1812 using or based on a UE-based TA measurement procedure. The UE-based TA measurement procedure may comprise determining the second TA based on a first TA of a serving or source cell (e.g., the first TA of cell 1808, or TA command 1806), a first timing difference (e.g., a timing difference 1814), and / or a second timing difference (e.g., a timing difference 1816).

[0299] In an example, wireless device 1802 may receive, via cell 1808, RS 1818 at (e.g., during or in) T 1820. T 1820 may be a first time interval (e.g., transmission time interval, time slot, slot, subframe, time period, time window, time, and / or the like). Wireless device 1802 may receive, via cell 1812, RS 1822 at (e.g., during or in) T 1824. T 1824 may be a second time interval. A difference between T 1820 and T 1824 may be or comprise timing difference 1814. The difference between T 1820 and T 1824 may be orDocket No.: 24-1257PCT comprise a difference between a first starting or ending time of T 1820 and a second starting or ending time of T 1824.

[0300] In an example, the first base station (e.g., a first DU, a first transmit and receive port (TRP), a first node, and the like) may transmit, via cell 1808, RS 1818 at (e.g., during or in) a T 1826. A second base station (e.g., a second DU, a second transmit and receive port (TRP), a second node, and the like) may transmit, via cell 1812, RS 1822 at (e.g., during or in) T 1828. A difference between ? 1826 and T 1828 may be or comprise the timing difference 1816. The difference between T 1826 and 1828 may be or comprise a difference between a third starting or ending time of T 1826 and a fourth starting or ending time of T 1828.

[0301] In an example, timing difference 1816 may be referred to as a reference signal time, timing, or transmit timing difference (RSTD). In an example, configuration(s) 1714 may indicate timing difference 1816. Timing difference 1816 may be of, for, associated with, corresponding to, or configured for cell 1812. Configuration(s) 1714 may comprise or indicate one or more RSTD values. The one or more RSTD values may be of, for, associated with, corresponding to, or configured for the one or more candidate / target cells. Each RSTD value, of the one or more RSTD values may be of, for, associated with, corresponding to, or configured for a respective candidate / target cell of the one or more candidate / target cells. In an example, the one or more RSTD values may comprise timing difference 1816. The one or more candidate / target cells may comprise, for example, cell 1812.

[0302] In an example, the wireless device 1802 may determine the second TA (value) associated with (e.g., of, for, or of a TAG comprising) cell 1812 using a first equation. The first equation may comprise, for example, the first TA. The first equation may comprise, for example, timing difference 1814. The first equation may comprise, for example, timing difference 1816. The first equation may be, for example, the second TA (value) = the first TA (value) + timing difference 1814 -timing difference 1816. The first equation may be, for example, the second TA (value) = the first TA (value) + timing difference 1814 + timing difference 1816.

[0303] In an example, the one or more candidate / target cells may not comprise cell 1812. In an example, cell 1812 may not be a candidate / target cell for an LTM procedure. In an example, cell 1812 may be: a serving cell, a non-serving cell, a secondary cell (SCell), a primary secondary cell (PSCell), a primary cell (PCell), an unlicensed cell, a cell configured for shared spectrum channel access, a cell comprised in a master cell group, a cell comprised in a secondary cell group, and / or an SCell configured for PUCCH.

[0304] FIG. 19 shows an example signal flow diagram as per an aspect of an embodiment of the present disclosure. The example of FIG. 19 may be used together with or independently from any of the previous examples (e g., FIGs 1A-18).Docket No.: 24-1257PCT

[0305] The example of FIG. 19 shows an example signal flow diagram for a conditional mobility procedure. The conditional mobility procedure may be or comprise, for example, a mobility or handover that is triggered by a wireless device without receiving a mobility or handover command (e.g., LTM cell switch command MAC CE, handover command, RRC message comprising ReconfigurationWithSync, RRC message comprising rachless-HO parameter(s), and the like). The conditional mobility procedure may comprise or be referred to as, for example, a conditional initiation of the LTM procedure. For example, the conditional mobility procedure may comprise (parts of) the LTM procedure as shown in FIG. 17 without (receiving) control command 1718. For example, the conditional mobility procedure may comprise one or more steps (e.g., elements or features) shown in FIG. 17 except for the wireless device receiving control command 1718.

[0306] In an example embodiment, the conditional mobility procedure may be the same as the LTM procedure.

[0307] In an example, the conditional mobility procedure may be referred to as conditional LTM (procedure).

[0308] In an example embodiment, the conditional mobility procedure may be the LTM procedure (e.g., as shown in FIG. 17), wherein early sync 1716 comprises an RAR-based random access procedure (e.g., a random access procedure comprising RAR reception or monitoring by a wireless device).

[0309] The conditional mobility procedure may be referred to, comprise, or be the same as, for example, a conditional mobility process or procedure. The conditional mobility procedure may be referred to, comprise, or be the same as, for example, an LTM procedure, a conditional LTM (C-LTM) procedure or process, a conditional (or conditionally) triggered LTM procedure or process, a conditional triggering of LTM procedure or process, a UE-initiated or triggered LTM (procedure or process), an autonomous LTM procedure, an enhanced conditional handover (eCHO) (procedure or process), a conditional handover (CHO) process or procedure, a RACH-less CHO (procedure or process), a RACH-less handover (procedure or process), a handover process or procedure, a UE-triggered handover (procedure or process), an LTM procedure with RAR (monitoring or reception) configured (e.g., enabled, allowed, required, needed) for early UL synchronization (e.g., early sync 1716), an RAR (monitoring or reception) configured (e.g., enabled, allowed, required, needed) for early UL synchronization for a mobility or LTM procedure.

[0310] The conditional mobility procedure may comprise a wireless device (e.g., wireless device 1702) triggering (e.g., performing or initiating) a cell switch based on fulfilling one or more conditions (e.g., events or conditional events), e.g., without receiving a handover command or LTM cell switch MAC CE.

[0311] The one or more candidate / target cells may be one or more candidate / target cells for the conditional mobility procedure.Docket No.: 24-1257PCT

[0312] For example, the conditional mobility procedure may comprise one or more steps (e.g., elements or features) shown in FIG. 19.

[0313] In the example of FIG. 19, a wireless device 1902 may transmit measurement report(s) 1908. The wireless device 1902 may be the same as or comprise, for example, the wireless device 1802 and / or wireless device 1702. Measurement report(s) 1908 may comprise or be the same as, for example, measurement report(s) 1704. Measurement report(s) 1908 may comprise, for example, layer 1 measurement report(s) (e.g., CSI-RS report(s), reference signal report(s), and the like) or layer 2 measurement report(s).

[0314] Wireless device 1902 may transmit measurement report(s) 1908 via a cell 1904. The cell 1904 may be, for example, a source or serving cell. Cell 1904 may be, for example, the same as cell 1808.

[0315] Cell 1904 may be, for example, the same as cell 1706.

[0316] Cell 1904 may be, for example, a SpCell, a PCell, and / or a PSCell.

[0317] Cell 1904 may be, for example, a SCell.

[0318] Cell 1904 may be, for example, a non-serving cell.

[0319] Wireless device 1902 may transmit or send measurement report(s) 1908 to a base station The base station may be a source or serving base station. For example, the base station may serve (e.g., be of, for, or serving) cell 1904. Wireless device 1902 may transmit or send measurement report(s) 1908 via PUSCH / PUCCH / SRS. The base station may receive measurement report(s) 1908 from wireless device 1902.

[0320] The base station may perform a mobility prep 1910, for example, in response to receiving measurement report(s) 1908. Mobility prep 1910 may comprise mobility preparation. Mobility prep 1910 may comprise or be the same as LTM prep 1708.

[0321] The base station may prepare or determine one or more candidate / target cells for a conditional mobility procedure, for example, at (e.g., during or in) a candidate preparation 1912. Candidate preparation 1912 may comprise or be the same as LTM candidate preparation 1710.

[0322] In the example of FIG. 19, the one or more candidate / target cells may comprise a cell 1906. Cell 1906 may be the same as, for example, cell 1712.

[0323] Candidate preparation 1912 may comprise a source base station (e.g., a source or serving gNB, a source or serving gNB-DU, a source or serving gNB-DU, and / or the like) communicating (e.g., transmitting, receiving, sending, and / or the like) with a candidate / target base station (e.g., a candidate / target gNB, a candidate / target gNB-DU, a candidate / target gNB-DU, and / or the like).

[0324] Cell 1904 and cell 1906 may be served, for example, by the same base station (e.g., gNB, gNB- DU, gNB-CU). For example, the conditional mobility procedure may be or comprise intra base station (e.g.,Docket No.: 24-1257PCT gN B, gNB-DU, gNB-CU) conditional mobility procedure based on the same base station (e.g., gNB, gNB- DU, gNB-CU) serving or being for or of cell 1904 and cell 1906.

[0325] Cell 1904 and cell 1906 may be served, for example, by different base stations (e.g., gNB, gNB- DU, gNB-CU). For example, the conditional mobility procedure may be or comprise inter base station (e.g., gNB, gNB-DU, gNB-CU) conditional mobility procedure based on different base stations (e.g., gNB, gNB- DU, gNB-CU) serving or being for or of cell 1904 and cell 1906.

[0326] In an example, cell 1906 may comprise or be the same as cell 1712. In an example, cell 1906 may comprise or be the same as cell 1812.

[0327] Cell 1906 may be, for example, a non-serving cell, an LTM candidate cell / candidate cell, a SCell, and / or an SpCell.

[0328] In an example, cell 1904 may be an unlicensed cell (e.g., operating with shared spectrum channel access). In an example, cell 1906 may be an unlicensed cell (e.g., operating with shared spectrum channel access).

[0329] In an example, cell 1904 may be a non-terrestrial network (NTN) cell. In an example, cell 1906 may be an NTN cell. For example, wireless device 1902 may be an NTN UE / wireless device

[0330] The base station may transmit or send message(s) 1914 to the wireless device 1902. The wireless device 1902 may receive the message(s) 1914. The wireless device 1902 may receive the message(s) 1914 from the base station.

[0331] The message(s) 1914 may be or comprise the one or more messages. The message(s) 1914 may be or comprise, for example, one or more RRC messages, one or more RRC reconfiguration messages, one or more RRC resume messages, one or more RRC release messages, and / or the like. In an example, the message(s) 1914 may be or comprise layer - 1 and / or layer - 2 message(s), e.g., MAC CE, DCI, PDCCH order, and / or the like. In an example, the message(s) 1914 may be or comprise one or more PDCCH messages / signals, PDSCH messages / signals, CSI-RSs, SIBs, SSBs, MIBs, and / or the like.

[0332] The message(s) 1914 may comprise one or more configuration parameters. The one or more configuration parameters may comprise one or more candidate / target cell configurations / configuration parameters (e.g., configuration(s) 1714). The one or more candidate / target cell configurations / configuration parameters may be referred to as one or more (candidate / target) LTM configurations / LTM configuration parameters.

[0333] The one or more candidate / target cell configurations or configuration parameters may be of (e.g., for, associated with, corresponding to, or configured for) to the one or more candidate / target cells. For example, each candidate / target cell configuration / configuration parameter, of the one or more candidate / target cell configurations / configuration parameters, may be of, for, associated with, corresponding to, or configured for a respective candidate / target cell of the one or more candidate / targetDocket No.: 24-1257PCT cells. In an example, the one or more configuration parameters may comprise or be the same as, for example, configuration(s) 1714.

[0334] In some aspects, the terms “configuration” and “configuration parameters” may be used interchangeably. It must be understood that the configuration may comprise the configuration parameters.

[0335] FIG. 20 shows an example as per an aspect of an embodiment of the present disclosure. The example of FIG. 20 may be used together with or independently from any of the previous examples (e.g., in FIGs. 1 A-19).

[0336] According to the example of FIG. 20, the base station and / or wireless device 1902 may perform an early sync 2002.

[0337] In an example, wireless device 1902 and / or the base station may perform early sync 2002. Early sync 2002 may comprise or be the same as, for example, early sync 1716. Early sync 2002 may be of, for, associated with, correspond to, or configured for to the conditional mobility procedure. In an example, early sync 2002 may be of, for, associated with, corresponding to, or configured for cell 1906 and / or cell 1904.

[0338] In an example, early sync 2002 may comprise or be an early UL synchronization procedure. In an example, message(s) 1914 may comprise one or more early UL synchronization configuration parameters (e.g., Early UL-SyncConfig). In an example, message(s) 1914 may comprise the one or more early UL synchronization configuration parameters for each candid ate / target cell of the one or more candidate / target cells.

[0339] In an example, a presence of the one or more early UL synchronization configuration parameters in message(s) 1914 may indicate (to wireless device 1902) that early sync 2002 is configured or enabled for the conditional mobility procedure (and / or for cell 1906). Cell 1906 may be a candidate / target cell of the one or more candidate / target cells.

[0340] In an example, wireless device 1902 may perform early sync 2002 based on, using, or as shown in the example of FIG. 18

[0341] In an example, early sync 2002 may comprise an RA procedure. The RA procedure may be the same as the RA procedure for early sync 1716. For example, early sync 2002 may comprise wireless device 1902 determining a TA (value) of a candidate / target cell (e.g., cell 1906) using the RA procedure.

[0342] In some aspects, a TA and a valid TA may be used interchangeably. A wireless device (e.g., wireless device 1902) determining a TA (value) may comprise the wireless device determining and / or validating the TA (value).

[0343] In some aspects, a TA may be referred to as a TA value.

[0344] An RA procedure may be referred to as, for example, an ETA procedure or process or ETA RA procedure The RA procedure may be referred to as, for example, LTM TA acquisition / early uplink sync.Docket No.: 24-1257PCT

[0345] The RA procedure may be triggered or initiated, for example, by the base station. The RA procedure may be triggered or initiated, for example, by wireless device 1902.

[0346] The base station may trigger or initiate the RA procedure, for example, by or via a downlink signal transmitted to wireless device 1902. The downlink signal may be or comprise downlink control information (e.g . , DCI format 1_0, physical downlink control channel (PDCCH) order, PDCCH message, and the like). The downlink signal may be or comprise a MAC CE (e.g., control command 1718).

[0347] In an example, there may be (only) one RA procedure (e.g., the RA procedure) ongoing at any point in time in wireless device 1902 (e.g., MAC entity of wireless device 1902).

[0348] In an example, wireless device 1902 may receive the downlink signal. The downlink signal may indicate (e.g , initiate or trigger) the RA procedure. For example, the downlink signal may be referred to as a PDCCH order.

[0349] The wireless device 1902 may transmit, e.g., for the RA procedure, a signal 2004.

[0350] In an example, the downlink signal may indicate signal 2004. For example, the downlink signal may indicate a transmission of signal 2004. In an example, the downlink signal may indicate a preamble index of signal 2004. In an example, the downlink signal may indicate a reference signal (RS) for transmitting signal 2004. Wireless device 1902 may use a radio link quality of the RS to determine a transmit power for or of signal 2004. The wireless device 1902 may transmit the signal 2004 with / using the transmit power. The downlink signal may indicate one or more resources (e.g., time resource, configuration index, frequency resource, and / or the like) for signal 2004. For example, wireless device 1902 may determine the one or more resources based on the RS (e.g., based on a mapping between the RS and the one or more resources indicated, e.g., by message(s) 1914). Wireless device 1902 may transmit signal 2004 via (e.g., using or with) the one or more resources.

[0351] Wireless device 1902 may transmit or send signal 2004 via cell 1906.

[0352] In an example, signal 2004 may be or comprise an RA preamble (e.g., PRACH transmission, preamble, Msg1 , RACH transmission, MsgA, and / or the like).

[0353] In an example, signal 2004 may comprise a reference signal (e.g., UL reference signal, sounding reference signal (SRS), SRS for positioning, and / or the like). In an example, signal 2004 may be a PUSCH or PUCCH transmission.

[0354] Wireless device 1902 may transmit signal 2004 via the one or more resources (e.g., RA resources). Message(s) 1914 may comprise or indicate the one or more resources. For example, the one or more early UL synchronization configuration parameters (e.g., Early UL-SyncConfig) may comprise or indicate the one or more resources. In an example, the downlink signal may comprise or indicate the one or more resources.Docket No.: 24-1257PCT

[0355] Wireless device 1902 may transmit signal 2004, for example, via cell 1904. The one or more resources may be, for example, for or of the cell 1904.

[0356] In an example, wireless device 1902 may transmit signal 2004 via cell 1906. The one or more resources may be, for example, for or of cell 1906.

[0357] Wireless device 1902 may monitor (e.g., receive or detect) (for) a signal 2006, for example, in response to (e.g., after, upon, or based on) transmitting signal 2004. Signal 2006 may, for example, correspond to signal 2004. For example, signal 2006 may comprise one or more identifiers (e.g., random access preamble identifiers) that match a preamble index of signal 2004. For example, signal 2006 may comprise a MAC subPDU with a random access preamble identifier corresponding to the preamble index of signal 2004.

[0358] In an example, wireless device 1902 may receive signal 2006 via cell 1906.

[0359] In an example, wireless device 1902 may receive signal 2006 via cell 1904 (as shown in FIG. 20).

[0360] In an example, wireless device 1902 may receive signal 2006 via a common search space (e.g., of or for cell 1904 and / or cell 1906).

[0361] In an example, early sync 2002 may comprise wireless device 1902 receiving signal 2006 as shown in FIG. 20.

[0362] Wireless device 1902 may monitor (for) signal 2006, for example, while a time window (e.g., ra- ResponseWindow, RAR window, RAR timer, and the like) is running.

[0363] In an example, signal 2006 may be or comprise a PDCCH for RAR identified by an RA-RNTI associated with signal 2004. In an example, signal 2006 may comprise or be the same as control command 1804. In an example, signal 2006 may comprise or be the same as control command 1810. In an example, signal 2006 may comprise TA command 1806. Signal 2006 may be or comprise, for example, downlink (DL) message(s).

[0364] In an example, signal 2006 may be a MAC CE. For example, signal 2006 may be a TA command MAC CE, absolute TA command MAC CE, C-LTM TA MAC CE, and / or candidate cell TA MAC CE. Signal 2006 may comprise a TA command. The TA command may indicate a TA value of or for cell 1906. For example, the TA command may indicate the TA value for a group (e.g., cell group, TA group, and / or any other group) comprising cell 1906. In an example, signal 2006 may be or comprise control command 1718.

[0365] In an example, message(s) 1914 may indicate whether (receiving or monitoring for) signal 2006 is configured (e.g., needed or required). For example, message(s) 1914 may indicate whether (receiving or monitoring for) signal 2006 is configured (e.g., needed or required), for each candidate / target cell of the one or more candidate / target cells. For example, message(s) 1914 may indicate whether (receiving or monitoring for) signal 2006 is configured (e.g., needed or required) for cell 1906.Docket No.: 24-1257PCT

[0366] The one or more candidate / target cells may be referred to as one or more LTM candidate cells, one or more candidate LTM cells, one or more target cells, one or more LTM target cells, and / or the like.

[0367] In an example, message(s) 1914 may indicate whether (receiving or monitoring for) signal 2006 is configured (e.g., needed or required) for cell 1906, via or based on the one or more early UL synchronization configuration parameters (e.g., Itm-EarlyUL-SyncConfig) indicating to whether (receiving or monitoring for) signal 2006 is configured (e.g., needed or required) for cell 1906.

[0368] For example, the one or more candidate / target cells may comprise a first cell (e.g., the cell 1906). The one or more candidate / target cells may comprise a second cell.

[0369] In an example, message(s) 1914 may indicate that (receiving or monitoring for) signal 2006 is configured (e.g., needed or required) (e.g., for early sync 2002) for the first cell. For example, message(s) 1914 may indicate that (receiving or monitoring for) signal 2006 is configured (e.g., needed or required) (e.g., for early sync 2002) for the first cell based on the one or more configuration parameters and / or the one or more early UL synchronization configuration parameters (e.g., Itm-EarlyUL-SyncConfig) indicating that (receiving or monitoring for) signal 2006 is configured (e.g., needed or required) (e.g., for early sync 2002) for the first cell.

[0370] The wireless device may monitor (e.g., detect or receive) (for) signal 2006 in response to (e.g., after, upon, or based on) transmitting signal 2004 via the first cell, for example, based on message(s) 1914 indicating that (receiving or monitoring for) signal 2006 is configured (e.g., needed or required) (e.g., for early sync 2002) for the first cell.

[0371] In an example, message(s) 1914 may indicate (receiving or monitoring for) signal 2006 is not configured (e.g., needed or required) (e.g., for early sync 2002) for the second cell. The wireless device may not monitor (e.g., detect or receive) (for) signal 2006, for example, in response to (e.g., upon, after, or based on) transmitting signal 2004 via the second cell, for example, based on message(s) 1914 indicating that (receiving or monitoring for) signal 2006 is not configured (e.g., needed or required) (e.g., for early sync 2002) for the second cell.

[0372] In an example, message(s) 1914 (e.g., the one or more configuration parameters and / or the one or more early UL synchronization configuration parameters (e.g., Itm-EarlyUL-SyncConfig)) may comprise a field indicating whether (receiving or monitoring for) signal 2006 is not configured (e.g., needed or required) (e.g., for the early sync 2002) for a cell (e.g., cell 1906, the first cell, the second cell, and the like). The field may be, for example, noRAR, RAwithRAR, conditionalLTM, and the like.

[0373] The field may indicate whether (receiving or monitoring for) signal 2006 is configured (e.g., needed or required) (e.g., for early sync 2002) for the cell based on a value of the field (e.g., based on the field being set to 1 , 0, true, false, yes, no, and the like). For example, the field may indicate (receiving or monitoring for) signal 2006 is configured (e.g., needed or required) (e.g., for early sync 2002) for the cellDocket No.: 24-1257PCT based on a value of the field being set to a first value (e.g., 1 , 0, true, false, yes, no, and the like). The field may indicate that (receiving or monitoring for) signal 2006 is not configured (e.g., needed or required) (e.g., for early sync 2002) for the cell based on a value of the field being set to a second value (e.g., 1 , 0, true, false, yes, no, and the like).

[0374] The field may indicate whether (receiving or monitoring for) signal 2006 is configured (e.g., needed or required) (e.g., for early sync 2002) for the cell based on a presence or absence of the field in message(s) 1914. For example, the field may indicate that (receiving or monitoring for) signal 2006 is configured (e.g., needed or required) (e.g., for early sync 2002) for the cell based on the field being present (or absent), e.g., in message(s) 1914 (and / or the one or more early UL synchronization configuration parameters). For example, the field may indicate that (receiving or monitoring for) signal 2006 is not configured (e.g., needed or required) (e.g., for early sync 2002) for the cell based on the field being absent (or present), e.g., in message(s) 1914 (and / or the one or more early UL synchronization configuration parameters).

[0375] In some aspects, monitoring may be the same as, comprise, or be referred to as detecting, receiving, decoding, and / or the like.

[0376] In an example, the first cell may be cell 1906 and / or cell 1904.

[0377] In an example, the second cell may be cell 1906 and / or cell 1904.

[0378] In an example, the first cell may be the same as the second cell.

[0379] In an example, the first cell may be different from the second cell.

[0380] At a step 2008, wireless device 1902 may determine a TA (value). The TA (value) may be associated with (e.g., for, with, of a group comprising) cell 1906.

[0381] The TA (value) may be associated with (e.g., for, with, of a group comprising) cell 1904.

[0382] In an example, early sync 2002 may comprise step 2008. For example, wireless device 1902 may perform step 2008 as part of (performing) early sync 2002.

[0383] The TA (value) may be of, for, associated with, corresponding to, or configured for a group (e.g., cell group, TA group (TAG), time-alignment group (TAG), master cell group, secondary cell group, and / or any other group of cells). The group may comprise (e.g., of, for, associated with, correspond to, or configured for) cell 1906.

[0384] In some aspects, a TA (value) being associated with a cell (e.g., cell 1906) may be referred to as the TA value being of, for, associated with, corresponding to, or configured for a group (e.g., cell group, TA group (TAG), time-alignment group (TAG), master cell group, secondary cell group, and / or any other group of cells) comprising the cell.

[0385] In an example, wireless device 1902 may determine the TA (value), e.g., at step 2008, based on (receiving) signal 2006. For example, signal 2006 may comprise a TA command (e.g., the TA commandDocket No.: 24-1257PCT1806). Wireless device 1902 may determine the TA (value) using the TA command. For example, wireless device 1902 may determine the TA (value) using an equation. The equation may comprise the TA command. The equation may be, for example, TA (value) = TA command*! 6*64 / 2Amu + offset, wherein mu indicates a subcarrier spacing. In an example, the offset may comprise N_TA, offset. In an example, the offset may comprise a two-way transmission delay on the service link based on NTuAEad)that wireless device 1902 determines using a serving satellite position and a position of wireless device 1902. The offset may comprise 7VT“ based on one-way propagation delay, for example, to pre-compensate a two-way transmission delay between an uplink time synchronization reference point and a serving satellite.

[0386] In an example, wireless device 1902 may determine (e.g., measure) the TA (value), e.g ., at step 2008, based on or using UE-based TA measurement as shown in FIG. 18 (e.g., without receiving a TA command associated with cell 1906).

[0387] A TA command or a TA value being associated with a cell (e.g., cell 1906, cell 1904) may be referred to as a TA command of, for, associated with, corresponding to, or configured for the cell (or of, for, associated with, corresponding to, or configured for a group (e.g., TAG) comprising the cell).

[0388] In an example, wireless device 1902 may determine (e.g., measure, estimate, calculate, compute, and the like) the TA (value) based on a location of wireless device 1902 and a location of the base station (or satellite). For example, wireless device 1902 may determine the TA (value) as twice the time taken for an electromagnetic signal to travel a distance between the location of wireless device 1902 and the location of the base station.

[0389] In an example, step 2008 may comprise wireless device 1902 determining the TA (value) of cell 1906. For example, step 2008 may comprise wireless device 1902 determining the TA (value) of, for, associated with, corresponding to, or configured for the group. The group may comprise cell 1906.

[0390] In an example, step 2008 (e.g., performing step 2008 or completing step 2008) may comprise wireless device 1902 successfully determining or measuring the TA (value).

[0391] In an example, step 2008 (e.g., performing step 2008 or completing step 2008) may comprise wireless device 1902 determining or measuring the TA (value) that is (determined to be) valid (e.g., validating the TA). The TA (value) may be, for example, (referred to as or same as) a valid TA (value).

[0392] In an example, step 2008 may comprise applying the TA (value) for one or more UL transmissions via cell 1906. In an example, step 2008 may comprise starting or restarting a time alignment timer associated with the TA group.

[0393] In an example, the group may be a primary TA group (PTAG). In an example, the group may be a secondary TA group (STAG).

[0394] For example, the group may be the PTAG based on comprising a SpCell / PCell (e.g., cell 1906).Docket No.: 24-1257PCT

[0395] In an example, step 2008 may comprise wireless device 1902 determining the TA (value) for cell 1906 (or the group comprising cell 1906) based on measuring the TA (value), e.g., as shown in FIG. 18.

[0396] In an example, step 2008 may comprise wireless device 1902 determining the TA (value) for cell 1906 (or the group comprising cell 1906) based on or using signal 2006.

[0397] In an example, the group may be a PTAG based on comprising a SpCell / PCell (e.g., cell 1904 or cell 1906).

[0398] FIG. 21 shows an example as per an aspect of an embodiment of the present disclosure. The example of FIG. 21 may be used together with or independently from any of the previous examples (e.g., in FIGs. 1A-20).

[0399] In the example of FIG. 21 , wireless device 1902 performs a step 2102 after receiving message(s) 1914.

[0400] In an example, wireless device 1902 may perform step 2102 after performing or completing step 2008.

[0401] In an example, wireless device 1902 may perform step 2102 before performing or completing step 2008.

[0402] In an example, wireless device 1902 may perform step 2102 and step 2008 in parallel (e.g., at the same time).

[0403] At step 2102, wireless device 1902 may perform one or more evaluations (e.g., conditional evaluations, conditional reconfiguration evaluations, evaluation of the one or more candidate / target (LTM) cell configurations / configuration parameters, the one or more configuration parameters, and the like).

[0404] The one or more evaluations may comprise determining (e.g., checking, estimating, testing, evaluating, examining, and the like) whether one or more conditions (e.g., events or conditional events) are fulfilled (e.g., satisfied or met). For example, message(s) 1914 may comprise or indicate the one or more conditions

[0405] In some aspects, "events”, “conditional events” and “conditions” may be used interchangeably.

[0406] In some aspects, “events”, “conditional events” and “conditions” may be, mean, or refer to the same. For example, the one or more conditions being fulfilled (e.g., satisfied, occurred, met) may comprise, be, mean, or refer to the one or more conditional events or one or more events being fulfilled.

[0407] One or more conditions being fulfilled may be referred to as the one or more conditions being satisfied, occurred, happened, realized, attained, complied, conformed, obeyed, adhered to, responded to, and / or met.

[0408] In some aspects, “events,” “conditions,” and / or “conditional events" may be used interchangeably (e.g , may be, comprise, refer to, or mean the same).Docket No.: 24-1257PCT

[0409] The one or more conditions may be for or used for determining whether to switch cells, e.g., from cell 1904 to cell 1906. The one or more conditions may be for or used for determining whether to switch a PCell or SpCell from cell 1904 to cell 1906. For example, in response to at least one (or each) condition, of the one or more conditions, being fulfilled, wireless device 1902 may (determine to) switch to cell 1906. For example, in response to at least one (or each) condition, of the one or more conditions, being fulfilled, wireless device 1902 may (determine to) switch from cell 1904 to cell 1906. For example, in response to at least one (or each) condition, of the one or more conditions, being fulfilled, wireless device 1902 may (determine to) switch an SpCell / PCell from cell 1904 to cell 1906.

[0410] The one or more conditions may comprise one or more first conditions. The one or more conditions may comprise one or more second conditions. The one or more first conditions may be for or used for determining whether to switch from cell 1904 to a first cell (e.g., cell 1906). The one or more second conditions may be for or used for determining whether to switch from cell 1904 to a second cell.

[0411] The conditional mobility procedure may comprise a cell switch procedure. The cell switch procedure may comprise wireless device 1902 switching from one cell to another (e.g., from cell 1904 to cell 1906).

[0412] Switching a cell may comprise switching from a first cell to a second cell (e.g., from cell 1904 to cell 1906). Switching a cell may comprise switching, moving, handover, changing, handing over, or transitioning to or from the cell. Switching from a first cell to a second cell may comprise changing, determining, setting, or assuming the second cell to be the SpCell after, based on, in response to, at, or during the switching. Switching from a first cell to a second cell may comprise changing, determining, setting, or assuming the first cell to be the SpCell before the switching.

[0413] The one or more conditions may comprise a first condition. The first condition may comprise (determining whether) a conditional reconfiguration candidate (e.g., a candidate cell, cell 1906, and the like) becoming amount of offset better than a SpCell (e.g., serving or source cell, cell 1904). For example, the first condition being fulfilled may comprise the conditional reconfiguration candidate (e.g., a candidate cell, cell 1906, and the like) becoming an amount of offset better than a SpCell (e.g., serving or source cell, the cell 1904). The first condition may be referred to as CondEvent A3, CondEvent LTM3, or Event-LTM3.

[0414] The one or more conditions may comprise a second condition (e.g., of, for, associated with, corresponding to, or configured for a candidate / target cell, cell 1906). The second condition may comprise (determining whether) a conditional reconfiguration candidate (e.g., a candidate cell, cell 1906, and the like) becoming better than a threshold. For example, the second condition being fulfilled may comprise (determining whether) the conditional reconfiguration candidate (e.g., a candidate cell, the cell 1906, and the like) becoming better than the threshold. The second condition may be referred to as CondEvent A4, CondEvent LTM4, or Event-LTM4. In an example, the one or more configuration parameters may compriseDocket No.: 24-1257PCT or indicate the threshold. In an example, message(s) 1914 and / or configuration(s) 1714 may comprise or indicate the threshold.

[0415] The one or more conditions may comprise a third condition (e.g., of, for, associated with, corresponding to, or configured for the candidate / target cell, cell 1906). The third condition may comprise (determining whether) the SpCell (e.g., serving or source cell, cell 1904) becoming worse than a first threshold and the conditional reconfiguration candidate becoming better than a second threshold. For example, the third condition being fulfilled may comprise (determining whether) the SpCell (e.g., serving or source cell, cell 1904) becoming worse than the first threshold and the conditional reconfiguration candidate (e.g., the candidate / target cell, cell 1906, and the like) becoming better than the second threshold. The third condition may be referred to as CondEvent A5, CondEvent LTM 5, or Event-LTM5. In an example, the one or more configuration parameters may comprise or indicate the first threshold and / or the second threshold. In an example, message(s) 1914 and / or configuration(s) 1714 may comprise or indicate the first threshold and / or the second threshold.

[0416] A cell becoming better than a threshold may comprise one or more radio link qualities of one or more RSs of, for, associated with, corresponding to, or configured for the cell being or becoming higher (e.g., greater, better, larger, and / or above) than the threshold. A cell becoming worse than a threshold may comprise one or more radio link qualities of one or more RSs of, for, associated with, corresponding to, or configured for the cell being or becoming lower (e.g., weaker, poorer, below, and / or less) than the threshold.

[0417] A first cell (e.g., cell 1906) becoming better than a second cell (e.g., cell 1904) may comprise one or more first radio link qualities of one or more first RSs of, for, associated with, corresponding to, or configured for the first cell being or becoming higher than one or more second radio link qualities of one or more second RSs of, for, associated with, corresponding to, or configured for the second cell.

[0418] The one or more conditions may comprise a fourth condition (e.g., of, for, associated with, corresponding to, or configured for the candidate / target cell, cell 1906). The fourth condition may comprise (determining whether) a distance between wireless device 1902 and a first reference location becoming larger than a first distance threshold and a distance between wireless device 1902 and a second reference location becoming shorter than a second distance threshold. For example, the fourth condition being fulfilled may comprise (determining whether) the distance between wireless device 1902 and the first reference location becoming larger than the first distance threshold and the distance between wireless device 1902 and the second reference location becoming shorter than the second distance threshold. The fourth condition may be referred to as CondEvent D1. In an example, the one or more configuration parameters may comprise or indicate the first distance threshold and / or the second distance threshold. InDocket No.: 24-1257PCT an example, message(s) 1914 and / or configuration(s) 1714 may comprise or indicate the first distance threshold and / or the second distance threshold.

[0419] The one or more conditions may comprise a fifth condition (e.g., of, for, associated with, corresponding to, or configured for the candidate / target cell, cell 1906). The fifth condition may comprise (determining whether) a time measured at wireless device 1902 becomes more than a first time threshold but is less than the first time threshold + a duration. For example, the fifth condition being fulfilled may comprise (determining whether) the time measured at wireless device 1902 becomes more than the first time threshold but is less than the first time threshold + the duration. The fifth condition may be referred to as CondEvent T1. In an example, the one or more configuration parameters may comprise or indicate the first time threshold and / or the duration. In an example, message(s) 1914 and / or config u ration (s) 1714 may comprise or indicate the first time threshold and / or the duration.

[0420] In an example, message(s) 1914 may indicate to wireless device 1902 that (receiving or monitoring for) signal 2006 is configured (e.g., needed or required) for cell 1906, for example, based on message(s) 1914 comprising or indicating the one or more conditions for cell 1906.

[0421] In an example, message(s) 1914 may indicate to wireless device 1902 that (receiving or monitoring for) signal 2006 is not configured (e.g., needed or required) for cell 1906, for example, based on message(s) 1914 not comprising or indicating the one or more conditions for cell 1906 (e.g., the one or more conditions for cell 1906 being absent in message(s) 1914).

[0422] Step 2102 may comprise the wireless device 1902 determining whether at least one (or each) condition, of the one or more conditions, are fulfilled.

[0423] At step 2102, wireless device 1902 may, for example, determine that at least one (or each) condition, of the one or more conditions, are fulfilled.

[0424] At step 2102, wireless device 1902 may, for example, determine that no conditions, of the one or more conditions, are fulfilled.

[0425] In an example, at step 2102, wireless device 1902 may determine that at least one (or each) condition, of the one or more conditions, are fulfilled. Wireless device 1902 (and / or the base station) may perform a mobility execution 2104, for example, based on the at least one (or each) condition, of the one or more conditions, being fulfilled.

[0426] Wireless device 1902 may not perform mobility execution 2104 (or switch to cell 1906) if no condition, of the one or more conditions, are fulfilled.

[0427] Wireless device 1902 may perform mobility execution 2104, for example, via (e.g., with, on, toward, in, or to) cell 1906.Docket No.: 24-1257PCT

[0428] In an example, mobility execution 2104 may comprise or be the same as the LTM execution 1726. In an example, mobility execution 2104 may comprise one or more elements, steps, processes, and / or procedures of LTM execution 1726 (e.g., receiving the RSs 1720, transmitting report(s) 1722, and the like).

[0429] Wireless device 1902 may transmit or send message(s) 2106. For example, wireless device 1902 may transmit message(s) 2106 as part of or based on (performing) mobility execution 2104. For example, mobility execution 2104 (e.g., wireless device 1902 performing mobility execution 2104) may comprise wireless device 1902 transmitting or sending message(s) 2106.

[0430] In an example, wireless device 1902 may transmit message(s) 2106 after (completing) mobility execution 2104.

[0431] In an example, wireless device 1902 may transmit message(s) 2106 before or prior to (starting) mobility execution 2104.

[0432] The wireless device 1902 may transmit or send message(s) 2106 to (e.g., for or via) the base station (e.g., the source or serving base station, the candidate / target base station, the source or serving or candidate / target gNB, the source or serving or candidate / target gNB-DU, the source or serving or candidate / target gNB-CU, and the like).

[0433] Wireless device 1902 may transmit or send message(s) 2106, for example, via cell 1904.

[0434] Wireless device 1902 may transmit or send message(s) 2106 via cell 1906. Wireless device 1902 may transmit or send message(s) 2106 via, for example, PUCCH (resource(s)). Wireless device 1902 may transmit or send message(s) 2106 via, for example, PUSCH (resource(s)). Wireless device 1902 may transmit or send message(s) 2106 via, for example, SRS (resource(s)).

[0435] Transmitting or receiving a signal via a channel (e.g., PUSCH, PUCCH, PRACH, and / or any other channel) may comprise or be referred to as transmitting or receiving the signal on, to, in, with, via, or over the channel (or resources of the channel).

[0436] Message(s) 2106 may be or comprise one or more RRC messages, one or more RRC reconfiguration complete messages, one or more RRC connection reconfiguration complete messages, and / or one or more PUSCH, PUCCH, or SRS transmissions.

[0437] In an example, wireless device 1902 may transmit or send message(s) 2106 via PRACH. Message(s) 2106 may comprise an RA preamble (e.g., Msg1 , PRACH transmission, RACH transmission, preamble, and / or the like).

[0438] In another example, message(s) 2106 may not comprise an RA preamble. Message(s) 2106 may not comprise a MsgA transmission (e.g., a PRACH and a PUSCH transmission).

[0439] Wireless device 1902 may transmit or send message(s) 2106 using the TA (value) (e.g., the TA (value) determined at the step 2008). For example, wireless device 1902 may adjust transmission or uplink timing (e.g., advance or delay) of message(s) 2106 by an amount of (or based on) the TA (value).Docket No.: 24-1257PCT

[0440] Wireless device 1902 may transmit or send the message(s) 2106 via one or more UL resources.

[0441] Transmitting or receiving a signal via one or more resources may be referred to as transmitting or receiving the signal using, with, based on, in, or on the one or more resources.

[0442] In some aspects, a signal may refer to a message, a channel, and / or a resource of, for, associated with, corresponding to, or configured for the channel.

[0443] In an example, message(s) 1914 may indicate the one or more UL resources (e.g., for message(s) 2106). In an example, message(s) 1914 may comprise or indicate one or more configured grant configurations. The one or more configured grant configurations may comprise or indicate the one or more UL resources (e.g., for message(s) 2106). Wireless device 1902 may transmit message(s) 2106 via (e.g., using, based on, with, in, on, over) the one or more UL resources.

[0444] In an example, wireless device 1902 may receive one or more DL messages via cell 1906 (e.g., during, at, or as part of mobility execution 2104). For example, wireless device 1902 may receive the one or more DL messages from the target base station (e.g., the candidate / target base station). The one or more DL messages may comprise or indicate the one or more UL resources (e.g., for message(s) 2106). The one or more DL messages may comprise or indicate one or more DL grants. The one or more DL grants may comprise or indicate the one or more UL resources. For example, the one or more DL grants may be or comprise one or more DCIs, MAC-CEs, PDCCH transmissions, PDSCH transmissions, and / or the like. For example, the one or more DL grants may be referred to as one or more dynamic grants.

[0445] In an example, wireless device 1902 may transmit or send message(s) 2106 using one or more spatial domain transmission filters (e.g., spatial filters, beams, spatial domain filters, spatial domain reception filter, spatial domain transmission filters, transmit beams) and / or one or more transmission configuration indication (TCI) states (e.g., joint TCI states, UL TCI states, DL-or-joint TCI states, and / or the like). Wireless device 1902 may determine the one or more spatial domain transmission filters and / or the one or more TCI states based on one or more RSs. For example, the one or more TCI states may be associated with the one or more RS (e.g., QCL type D relation or pathloss RS for the one or more TCI states). The one or more RSs may be associated with (e.g., indicate or be mapped to) the one or more UL resources.

[0446] The wireless device may determine the one or more RSs based on the one or more RSs fulfilling the one or more conditions.

[0447] Message(s) 1914 and / or the one or more configuration parameters may comprise or indicate the one or more spatial domain transmission filters. For example, message(s) 1914 and / or the one or more configuration parameters may comprise or indicate the one or more TCI states. For example, message(s) 1914 and / or the one or more configuration parameters may comprise or indicate the one or more RSs. ForDocket No.: 24-1257PCT example, message(s) 1914 and / or the one or more configuration parameters may comprise or indicate that the one or more RSs are associated with the one or more UL resources.

[0448] In an example, the one or more DL messages may indicate or activate the one or more spatial domain transmission filters (or the one or more TCI states). For example, the one or more DL grants may indicate or activate the one or more spatial domain transmission filters (or the one or more TCI states).

[0449] Message(s) 2106 may be referred to as one or more initial UL transmissions via a candidate / target cell (e.g ., cell 1906). For example, message(s) 2106 may be referred to as one or more initial UL transmissions via cell 1906. For example, message(s) 2106 may be the first (e.g., first in time) UL transmission via cell 1906 after (or during or at) mobility execution 2104.

[0450] In some aspects, wireless device 1902 may transmit or send message(s) 2106 after mobility execution 2104 (e.g., mobility execution 2104 may not comprise wireless device 1902 transmitting message(s) 2106).

[0451] In the example of FIG. 17 (e.g., for an LTM procedure), configuration(s) 1714 may indicate that (monitoring for) a random access response is not configured (e.g., needed or required) (e.g., for early sync 1716) based on the base station indicating a first TA (e.g., associated with cell 1712) via (e.g., in, through, or by) control command 1718.

[0452] In some aspects, a TA associated with a cell may be the same as or indicate the TA being of, for, associated with, corresponding to, or configured for the cell (or a group (e.g., TAG) comprising the cell).

[0453] In the example of FIG. 19 (e.g., for a conditional mobility procedure), message(s) 1914 may indicate that (monitoring for) signal 2006 is configured (e.g., needed or required) (e.g., for early sync 2002) for cell 1906. The base station may indicate that (monitoring for) the signal 2006 is configured (e.g., needed or required) (e.g., for early sync 2002) for cell 1906, for example, due to wireless device 1902 determining to switch from cell 1904 to cell 1906 without receiving a control command (e.g., control command 1718) indicating (e.g., triggering or initiating) the switch. The base station may indicate that (monitoring for) the signal 2006 is configured (e.g., needed or required) (e.g., for the early sync 2002) for the cell 1906, for example, due to wireless device 1902 determining the TA (value) associated with cell 1906 during early sync 2002 (e.g., at step 2008).

[0454] In an example, the one or more messages (e.g , RRC message, MAC CE, DCI, PDCCH order, message(s) 1914, and the like) may indicate to wireless device 1902 whether RAR is needed for PDCCH ordered RACH for a candidate / target cell in LTM. For example, configuration(s) 1714 (e.g., a / each candidate / target (LTM cell) configuration of configuration(s) 1714) may indicate whether RAR is needed (e.g., RAR monitoring is required, RAR is configured, and the like) for an RA procedure (e.g., RA preamble transmission, PRACH transmission, and the like) initiated or triggered by the downlink signal via the candidate / target cell of the one or more candidate / target cells (e.g., for early sync 2002). For example,Docket No.: 24-1257PCT a / each candidate / target (LTM cell) configuration, of configuration(s) 1714, may comprise a parameter indicating whether RAR is configured (e.g., needed or required) (e.g., noRAR within or comprised in LTM- EarlySyncConfig information element, which may be comprised in the candidate / target (LTM cell) configuration of configuration(s) 1714).

[0455] In some aspects, the terms “field” and “parameter” may be used interchangeably and / or mean the same.

[0456] For example, a first candidate / target (LTM cell) configuration, of configuration(s) 1714, may be associated with a first candidate / target cell (e.g., cell 1906) of the one or more candidate / target cells. A second candidate / target (LTM cell) configuration, of configuration(s) 1714, for example, may be associated with a second candidate / target cell of the one or more candidate / target cells.

[0457] In an example, the first candidate / target (LTM cell) configuration may indicate that RAR is needed (e.g., RAR monitoring is configured (e.g., needed or required), RAR is expected by wireless device 1902, RAR monitoring is configured, RAR is configured, and the like) for (e.g., an RA procedure associated with) the first candidate / target cell, of the one or more candidate / target cells (e.g., noRAR may be set to false). In response to transmitting an RA preamble for an RA procedure that is triggered or initiated by a (layer-1) control command for LTM (e.g., for / via the first candidate / target cell), wireless device 1902 may monitor (for) a PDCCH for Random Access Response (RAR) identified by an RA-RNTI associated with (or corresponding to) the PRACH transmission (e.g., while a ra-ResponseWindow (e.g., RAR window, RAR timer, and the like) is running).

[0458] In an example, wireless device 1902 may not receive an RAR identified by an RA-RNTI associated with (or corresponding to) the RA preamble (e.g., while a ra-ResponseWindow (e.g., RAR window, RAR timer, and the like) is running). Wireless device 1902 may increment a counter (e.g., preamble transmission counter), for example, based on not receiving an RAR identified by an RA-RNTI associated with (or corresponding to) the RA preamble (e.g., while a ra-ResponseWindow (e.g., RAR window, RAR timer, and the like) is running).

[0459] In an example, the ra-ResponseWindow (e.g., RAR window, RAR timer, and the like) may expire. Wireless device 1902 may not receive an RAR containing or corresponding to the RA preamble (or RA preamble identifiers). Wireless device 1902 may increment the counter, for example, based on the ra- ResponseWindow (e.g., RAR window, RAR timer, and the like) expiring and / or not receiving an RAR containing / corresponding to the RA preamble (or RA preamble identifiers).

[0460] In another example, the second candidate / target (LTM cell) configuration may indicate that RAR is not needed (e.g., RAR monitoring is not configured (e.g., needed or required), RAR is not expected by wireless device 1902, RAR monitoring is not configured, RAR is not configured, and the like) for (e.g , an RA procedure associated with) the second candidate / target cell, of the one or more candidate / target cellsDocket No.: 24-1257PCT(e.g., noRAR may be set to true). In response to transmitting an RA preamble for an RA procedure that is triggered / initiated by a (layer-1) control command for LTM (e.g., for / via the first candidate / target cell), wireless device 1902 may not monitor or receive (for) a PDCCH for Random Access Response(s) identified by an RA-RNTI associated with (or corresponding to) the RA preamble (e.g., while a ra-ResponseWindow (e.g., RAR window, RAR timer, and the like) is running).

[0461] In some aspects, the terms “TA” and “TA value” may be used interchangeably in the present disclosure.

[0462] In some aspects, PRACH transmission may be the same as or be referred to as RA preamble, RA preamble transmission, preamble, preamble transmission, Msg 1 , Msg 1 transmission, PRACH, RACH, RACH transmission, Msg A, Msg A transmission, Msg A PRACH, Msg A PRACH transmission, and / or any other message of an RA procedure.

[0463] A four-step RA procedure may comprise a wireless device transmitting a Msg 1 , receiving a Msg 2, transmitting a Msg 3, and receiving a Msg 4 (e.g., in that order). The wireless device may complete (e.g., end) the four-step RA procedure after or based on receiving the Msg 4 or transmitting a HARQ-ACK for or of the Msg 4

[0464] A two-step RA procedure may comprise the wireless device transmitting a Msg A and receiving a Msg B. The wireless device may complete (e.g., end) the two-step RA procedure after or based on receiving the Msg B and / or transmitting a HARQ-ACK for or of the Msg B.

[0465] A one-step RA procedure may comprise the wireless device transmitting a PRACH transmission The wireless device may end the one-step RA procedure after or based on transmitting the PRACH transmission. The wireless device may not receive any downlink signals or messages for or during the one- step RA procedure.

[0466] FIG. 22 illustrates an example as per an aspect of an embodiment of the present disclosure. The example of FIG. 22 may be used together with or independently from any of the previous examples (e.g., in FIGs. 1A-21).

[0467] In the example of FIG. 22, a wireless device 2200 receives configuration(s) 2202. Wireless device 2200 may be the same as wireless device 1702, wireless device 1802, and / or wireless device 1902. Configuration(s) 2202 may be the same as or comprise configuration(s) 1714. In an example, message(s) 1914 may comprise or indicate configuration(s) 2202.

[0468] Configuration(s) 2202 may be or comprise one or more candidate / target (LTM cell) configurations. Configuration(s) 2202 may be for a conditional mobility procedure (e.g., conditional LTM) as described in the previous examples. Config u ration (s) 2202 may be for the one or more candidate / target cells. Each configuration, of configuration(s) 2202, may be for a respective candidate / target cell of the one or more candidate / target cells.Docket No.: 24-1257PCT

[0469] In the example of FIG. 22, wireless device 2200 receives a signal 2204. Signal 2204 may be the same as or comprise the downlink signal as described above. Signal 2204 may be, for example, a DCI (e.g., DCI of format 1_0). Signal 2204 may be referred to as a PDCCH order. Signal 2204 may be or comprise, for example, a MAC CE (e.g., control command 1718).

[0470] Signal 2204 may indicate (e.g., initiate or trigger) an RA procedure 2208. RA procedure 2208 may be the same as the RA procedure described above for any of the previous embodiments. RA procedure 2208 may be for or of early UL synchronization. For example, RA procedure 2208 may be for or of early sync 2002 and / or early sync 1716.

[0471] An RA procedure (e.g., RA procedure 2208) being for an early sync procedure (e.g., early sync 2002 and / or early sync 1716) may be or indicate the RA procedure being performed by a wireless device (e.g., wireless device 2200) for or as part of the early sync procedure.

[0472] Signal 2204 may indicate (e.g., initiate or trigger) RA procedure 2208. Signal 2204 may indicate a signal 2206 for RA procedure 2208. For example, signal 2204 may comprise or indicate an RA preamble index field that indicates an RA preamble index of signal 2206. Wireless device 2200 may transmit signal 2206, for RA procedure 2208, based on (receiving) signal 2204 indicating signal 2206. In an example, signal 2206 may be the same as or comprise signal 2004. Signal 2206 may be or comprise a PRACH transmission.

[0473] Signal 2204 may comprise or indicate a frequency domain resource assignment field. The frequency domain resource assignment field may indicate one or more frequency domain resources of or for transmitting signal 2206. In an example, the frequency domain resource assignment field may be set to all ones. Signal 2204 may be for or initiates RA procedure 2208 (by a PDCCH order) based on the frequency domain resources assignment field being set to all ones.

[0474] Signal 2204 may comprise or indicate a SS / PBCH index field. The SS / PBCH index field may indicate an RS to use for RA procedure 2208. For example, wireless device 2200 may use the RS to determine one or more resources via which wireless device 2200 transmits signal 2206. Wireless device 2200 may use the RS to determine a pathloss and / or a transmit power to transmit signal 2206. For example, wireless device 2200 may determine a pathloss based on measuring the RS. Wireless device 2200 may determine the transmit power based on or using the pathloss (e.g., the transmit power = preamble received target power - pathloss + offset). Wireless device 2200 may transmit signal 2206 using or with the transmit power.

[0475] Signal 2204 may comprise or indicate a PRACH mask index field. The PRACH mask index field may indicate one or more PRACH occasions (e.g., the one or more resources) via which wireless device 2200 transmits signal 2206. For example, the RS may indicate (e.g., be mapped to) PRACH occasion(s). The PRACH mask index field may indicate the one or more PRACH occasions from or among the PRACHDocket No.: 24-1257PCT occasion(s). Wireless device 2200 may transmit signal 2206 using or via the one or more PRACH occasions.

[0476] In some aspects, one or more resources may be referred to or replaced with one or more PRACH occasions.

[0477] Transmitting a signal (e.g., signal 2206 or signal 2004) via a PRACH occasion (e.g., the one or more PRACH occasions) may be the same as, be, comprise, or be referred to as transmitting the signal on, in, overlapping with, via, over, towards, using, based on, associated with, of, for, configured in, configured for, configured with, and / or corresponding to the PRACH occasion.

[0478] Signal 2204 may comprise or indicate a cell indicator field. The cell indicator field may indicate a cell via which wireless device 2200 transmits (or should transmit) signal 2206. The cell indicator field may indicate a cell from or among the one or more candidate / target cells. For example, the cell may be a candidate / target cell of the one or more candidate / target cells. Wireless device 2200 may transmit signal 2206 via the cell based on signal 2204 indicating the cell.

[0479] In the example of FIG. 22, wireless device 2200 receives signal 2204 via a cell 2210. In an example, cell 2210 may be the same as cell 1904, cell 1808, and / or cell 1706. For example, cell 2210 may be a source or serving cell of wireless device 2200. For example, cell 2210 may be a SpCell, PCell, PSCell, and / or an SCell of or for wireless device 2200.

[0480] The cell indicator field may indicate a cell 2220. Cell 2220 may be the same as, for example, cell 1906, cell 1812, and / or cell 1712. Cell 2220 may be a candidate / target cell of the one or more candidate / target cells (e.g., for LTM or conditional LTM procedure). Wireless device 2200 may transmit signal 2206 via cell 2220 based on the cell indicator field in signal 2204 indicating cell 2220.

[0481] Signal 2204 may comprise or indicate a PRACH retransmission indicator field. The PRACH retransmission indicator field may indicate initial transmission or retransmission of signal 2206 (e.g., a first value of the PRACH retransmission indicator field may indicate initial transmission of signal 2206 and a second value of the PRACH retransmission indicator field may indicate retransmission of signal 2206), e.g., in response to (or if) the cell indicator field indicates a candidate / target cell (e.g., cell 2220). Wireless device 2200 may ignore the PRACH retransmission indicator field if the cell indicator field indicates a serving cell (e.g , cell 2210) but not a candidate / target cell (e.g., cell 2220).

[0482] In an example, signal 2206 may be a PRACH transmission. For example, signal 2206 may be or comprise signal 2004. Signal 2204 may be, for example, the downlink signal described in the previous other embodiments in the present disclosure.

[0483] In an example, wireless device 2200 may determine condition(s) 2212 to be fulfilled while RA procedure 2208 is ongoing. Condition(s) 2212 may be the same as the one or more conditions described in the previous embodiments.Docket No.: 24-1257PCT

[0484] In some aspects, mobility execution 2104 may comprise cell switch. Cell switch may be referred to as executing or performing cell switch or cell switch execution.

[0485] In existing technologies, a wireless device may complete an ongoing RA procedure (e.g., for early uplink synchronization) before switching to a candidate / target cell. For example, the wireless device may delay execution of cell switch when one or more conditions for cell switch are met while the RA procedure is ongoing. This approach may be beneficial since completing early uplink synchronization before cell switch (e.g., acquire TA for the candidate / target cell) may reduce mobility latency. However, this approach may not always be suitable, e.g., when results of the early uplink synchronization are wrong or not useful. The implementation of the existing technologies may result in excessive interruption time during mobility in some scenarios, e.g., when multiple candidate cells are configured for conditional mobility and early uplink synchronization is performed for a wrong cell.

[0486] Embodiments of the present disclosure are related to an approach for solving the problems described above. These and other features of the present disclosure are described further below.

[0487] In an example embodiment, a wireless device transmits via a candidate cell of candidate cells, an RA preamble of an RA procedure (e.g , early uplink synchronization) for or of cell switch. The wireless device stops (or aborts) the RA procedure based on: determining to switch to a first candidate cell, of the candidate cells, while the RA procedure is ongoing; and the first candidate cell being different from the candidate cell.

[0488] Example embodiments of the present disclosure may reduce interruption time during mobility. By stopping an RA procedure, via a candidate cell, that was ongoing while determining to switch to a first candidate cell that is different from the candidate cell, the wireless device may save time in switching to the first candidate cell without waiting to complete the RA procedure via the candidate cell. However, if the wireless device determines to switch to the candidate cell while the RA procedure, via the candidate cell, is ongoing, the wireless device may wait to complete the RA procedure before switching to the candidate cell. If the ongoing RA procedure and the cell switch conditions being fulfilled are for the same candidate cell, the wireless device may wait to complete the ongoing RA procedure before switching to the candidate cell. This enables the wireless device to skip an RA procedure after cell switch by completing the ongoing RA procedure (e.g., while being connected to the serving cell). As a result, interruption time during mobility may be reduced. This may result in smooth cell switches, e.g., without a call-drop or video buffering during cell switch or during mobility.

[0489] In an example embodiment, the wireless device may stop (or abort) the ongoing RA procedure, based on a first radio link quality of a first RS (e.g., indicating by a PDCCH order that triggered the ongoing RA procedure) is worse than a second radio link quality of a second RS associated with the candidate cell. This enables the wireless device to stop an RA procedure that could potentially fail (e.g., preambleDocket No.: 24-1257PCT transmissions for the RA procedure may fail) due to there being a better RS (that is, the second RS) than the one (that is, the first RS) indicated by the PDCCH order that triggers the ongoing RA procedure.

[0490] Example embodiments of the present disclosure may reduce interruption latency and / or signaling overhead associated with multiple preamble retransmissions. Reducing signaling overhead may result in improvement in battery life of the wireless device and more efficient use of network resources.

[0491] FIG. 23 illustrates an example signal flow diagram as per an aspect of an embodiment of the present disclosure. The example of FIG. 23 may be used together with or independently from any of the previous examples (e.g., in FIGs. 1A-22).

[0492] In the example of FIG. 23, a wireless device 2300 receives configuration(s) 2302. In an example, wireless device 2300 may be the same as wireless device 2200. Configuration(s) 2302 may be the same as configuration(s) 2202.

[0493] Configuration(s) 2202 may be or comprise one or more candidate / target (LTM cell) configurations for a conditional mobility procedure. Configuration(s) 2202 may be for (e.g., of, for, associated with, corresponding to, or configured for) the one or more candidate / target cells.

[0494] In the example of FIG. 23, the one or more candidate / target cells may comprise a cell 2310, a cell 2320 and / or a cell 2330. Cell 2310 may be, for example, a serving cell of the wireless device (e.g., SpCell or SCell). The one or more candidate / target cells may be for (e.g., of, for, associated with, corresponding to, or configured for) the conditional mobility procedure (e.g., CHO, LTM, C-LTM).

[0495] In an example cell 2310 may be the same as cell 2210.

[0496] In an example, cell 2320 may be the same as cell 2220.

[0497] In an example, cell 2330 may be the same as cell 2220.

[0498] Configuration(s) 2302 may comprise or indicate a candidate / target (LTM cell) configuration for or of cell 2320. Configuration(s) 2302 may comprise or indicate a candidate / target (LTM cell) configuration for or of cel I 2330.

[0499] In an example, wireless device 2300 may receive a signal 2304. Signal 2304 may be the same as signal 2204.

[0500] In some aspects, a signal may be referred to as a message, information, transmission, channel, resource, resource of a channel, signal of a channel, and / or any other transmission

[0501] Wireless device 2300 may receive signal 2304 via PDCCH (or PDSCH). Signal 2304 may comprise or indicate a downlink control information (DCI). For example, signal 2304 may be or comprise or indicate a DCI of or with format X_Y, where X = 0, 1 , 2, ... and Y = 0, 1 , 2, 3, ...

[0502] Signal 2304 may be or comprise a MAC CE (e.g., control command 1718).

[0503] Signal 2304 may indicate (e.g , trigger or initiate) an RA procedure 2308. RA procedure 2308 may be, for example, the same as RA procedure 2208. RA procedure 2308 may be of, for, associated with,Docket No.: 24-1257PCT corresponding to, or configured for an early uplink synchronization procedure (e.g., early sync 2002 and / or early sync 1716). RA procedure 2308 may be via (e.g., of, for, associated with, corresponding to, or configured for, to, toward, or in) cell 2320, e.g., as shown in FIG. 23.

[0504] RA procedure 2308 may be a contention-based RA procedure, a contention-free RA procedure, a type-1 RA procedure, a four-step RA procedure, a type-2 RA procedure, a two-step RA procedure, a one- step RA procedure, and / or any other type of RA procedure (e.g., as described above).

[0505] Signal 2304 may indicate (e.g., initiate or trigger) a transmission of a signal 2306. In an example, signal 2306 may be the same as signal 2206. For example, signal 2306 may be or comprise a PRACH transmission. Wireless device 2300 may transmit signal 2306 for RA procedure 2308. Wireless device 2300 may transmit signal 2306 via cell 2320.

[0506] In an example, wireless device 2300 may determine condition(s) 2312 to be fulfilled while (e.g., when or during) RA procedure 2308 is ongoing. For example, wireless device 2300 may determine condition(s) 2312 to be fulfilled after receiving signal 2304. Wireless device 2300 may determine condition(s) 2312 to be fulfilled after receiving signal 2304, before transmitting signal 2306, after transmitting signal 2306, and / or before receiving a response (e.g., RAR or MAC CE) in response to transmitting signal 2306.

[0507] In an example, condition(s) 2312 may be the same as condition(s) 2212. In an example, condition(s) 2312 may be or comprise the one or more conditions described above (e.g., with respect to FIG 21). Condition(s) 2312 may be of, for, associated with, corresponding to, or configured for cell 2330. Cell 2330 may be the same as, for example, cell 1906.

[0508] In an example, RA procedure 2308 may be ongoing based on (e.g., in response to, during, or after): receiving signal 2304; receiving signal 2304 triggering or initiating RA procedure 2308; receiving signal 2304 indicating a transmission of signal 2306; determining one or more resources to transmit signal 2306; transmitting signal 2306; monitoring (e.g , detecting or receiving) a common search space to receive a response (e.g., RAR) in response to (e.g., after, of, for, associated with, corresponding to, or configured for) signal 2306; monitoring a dedicated (UE-specific search space) to receive a response (e.g., MAC CE, a message scrambled by C-RNTI) in response to (e.g., after, of, for, associated with, corresponding to, or configured for) signal 2306; reselecting one or more resources for transmitting signal 2306; and / or retransmitting signal 2306.

[0509] In an example, wireless device 2300 may stop RA procedure 2308 (e.g., ongoing RA procedure) based on (e.g., in response to, upon, after, during): determining condition(s) 2312 (e.g., of, for, associated with, corresponding to, or configured for cell 2330) to be fulfilled; RA procedure 2308 being of, for, associated with, corresponding to, or configured for cell 2320; and / or cell 2330 being different from cell 2320.Docket No.: 24-1257PCT

[0510] Stopping an RA procedure (e.g., RA procedure 2308) may refer to (e.g., be the same as or comprise) aborting, ending, suspending, canceling, terminating, finishing, ceasing, concluding, completing, pausing, discontinuing, halting, abandoning, releasing, flushing, quitting, interrupting, shutting down, deactivating, and / or disabling the RA procedure.

[0511] Wireless device 2300 may transmit a signal 2314 via cell 2330. In an example, wireless device 2300 may transmit signal 2314 after stopping RA procedure 2308.

[0512] In an example, signal 2314 may be or comprise a PRACH transmission. Signal 2314 may be or comprise a PRACH transmission based on a (valid) TA of, for, associated with, corresponding to, or configured for cell 2330 not being available (e.g., at or with wireless device 2300).

[0513] In another example, signal 2314 may be or comprise a PUSCH transmission (e.g., CG-PUSCH transmission). Signal 2314 may be a PUSCH transmission based on a (valid) TA of, for, associated with, corresponding to, or configured for cell 2330 being available (e.g., at or with wireless device 2300).

[0514] In some aspects, TA may refer to timing advance, timing advance value, timing adjustment, timing adjustment value, and / or any other term indicating adjusting uplink transmission timing.

[0515] A (valid) TA of, for, associated with, corresponding to, or configured for cell 2330 may be available (e.g., at or with wireless device 2300) based on (e.g., in response to, upon, or after) wireless device 2300 successfully completing an early uplink synchronization procedure (e.g., early sync 2002, early sync 1716, and / or step 2008) via cell 2330 (e.g., receiving an RAR or a MAC CE indicating the (valid) TA). For example, a (valid) TA may be available based on (e.g., in response to, upon, or after) wireless device 2300 successfully measuring the (valid) TA of, for, associated with, corresponding to, or configured for cell 2330 using a UE-based TA measurement procedure (e.g., as shown in FIG. 18, e.g., cell 2330 may be the same as cell 1812 and condition(s) 2312 may be the same as cell 1808).

[0516] A (valid) TA may be available based on (e.g., in response to, upon, or after) wireless device 2300 receiving the valid TA of, for, associated with, corresponding to, or configured for cell 2330 (e.g., via cell 2310 and / or cell 2330). A (valid) TA may be available based on (e.g., in response to, upon, or after) a timer (e.g., time alignment timer, uplink synchronization validity timer, early uplink synchronization validity timer) running (e.g., at or with wireless device 2300). Configuration(s) 2302 may comprise or indicate (e.g., configure) the timer. Wireless device 2300 may start the timer based on (e.g., in response to, upon, or after) receiving the (valid) TA (e.g., via RAR or MAC CE).

[0517] A (valid) TA being available may refer to a TA being valid, validating a TA, determining a (valid) TA, and / or successfully determining (e.g., receiving or measuring) a (valid) TA.

[0518] In an example, a candidate / target (LTM cell) configuration, of configuration(s) 2302, that is of, for, associated with, corresponding to, or configured for cell 2330 may comprise or indicate one or more (UL) resources (e.g., time, frequency, and / or beam-related resources) signal 2314. Wireless device 2300 mayDocket No.: 24-1257PCT transmit signal 2314 via (e.g., using, based on, with, on, in, of, for, associated with, corresponding to, or configured for) the one or more (UL) resources.

[0519] FIG. 24 illustrates an example flowchart as per an aspect of an embodiment of the present disclosure. The example of FIG. 24 may be used together with or independently from any of the previous examples (e.g., in FIGs. 1A-23).

[0520] According to the example of FIG. 24, at step 2402, a wireless device (e.g., wireless device 2300, wireless device 2200) receives configuration parameters. For example, configuration(s) 2302 may comprise or indicate the configuration parameters. The wireless device may receive the configuration parameters via a serving cell (e.g., cell 2310). The configuration parameters may be for a conditional mobility procedure. The configuration parameters may be of, for, associated with, corresponding to, or configured for a first candidate cell (e.g., cell 2330) of the one or more candidate / target cells. The configuration parameters may comprise or indicate a condition (e.g., condition(s) 2312) to switch to a first candidate cell (e.g., cell 2330).

[0521] For brevity, the example of FIG. 24 refers to condition(s) 2312 as the condition. It is to be understood that the condition may be replaced with (or comprise) the one or more conditions (e.g., as described above in any of the previous examples). The condition being fulfilled may refer to or be replaced with each (or at least one) of the one or more conditions being fulfilled.

[0522] At step 2404, the wireless device receives a PDCCH order (e.g., signal 2304). The wireless device may receive the PDCCH order via the serving cell (e.g., cell 2310). The PDCCH order may indicate (e.g., initiate or trigger) an RA procedure (e.g., RA procedure 2308, RA procedure 2208). The RA procedure may be for early uplink synchronization (e.g., early sync 2002, early sync 1716), e.g., via a second candidate cell (e.g., cell 2320). The one or more candidate / target cells may comprise the second candidate cell. The RA procedure may be via (e.g., of, for, associated with, corresponding to, or configured for) the second candidate cell (e.g., cell 2320).

[0523] In an example, step 2404 may be after step 2402.

[0524] In some aspects, step 2404 may be before step 2402.

[0525] At step 2406, the wireless device may determine the condition (e.g., condition(s) 2312) to be fulfilled. The wireless device may determine the condition to be fulfilled while (e.g., when or during) the RA procedure is ongoing. The RA procedure may be ongoing, for example, based on (e.g., in response to, during, at, after): receiving the PDCCH order; the PDCCH order indicating a PRACH transmission for the RA procedure; determining (e.g., selecting) one or more resources (e.g., PRACH occasions) for the PRACH transmission; transmitting the PRACH transmission; monitoring a search space (e.g., common search space, Type-1 CSS, UE-dedicated search space (USS), and / or any other type of search space); monitoring the search space for a response (e.g., RAR, MAC CE, RA response corresponding to the PRACH transmission, RA response comprising a preamble index of, for, associated with, corresponding to,Docket No.: 24-1257PCT or configured for the PRACH transmission); starting a window (e.g., an RAR window) in response to transmitting the PRACH transmission; and / or the window running.

[0526] In an example, step 2406 may be after step 2404 and / or step 2402.

[0527] In some aspects, step 2406 may be before step 2404 and / or step 2402.

[0528] At step 2408, the wireless device may determine whether to stop or continue the RA procedure (e.g., the ongoing RA procedure) based on whether the first candidate cell is the same as the second candidate cell (that is, based on whether the condition is satisfied for the same candidate cell via which the RA procedure is ongoing).

[0529] In an example, the first cell may be different from the second cell. For example, at step 2408, the wireless device may determine that the first cell is different from the second cell. The wireless device may perform step 2412 based on (e.g., in response to, upon, or after): the first cell being different from the second cell; determining that the first cell is different from the second cell; the condition being fulfilled while the RA procedure is ongoing; determining the condition to be fulfilled while the RA procedure is ongoing.

[0530] In another example, the first cell may be the same as the second cell. For example, at step 2408, the wireless device may determine that the first cell is the same as the second cell. The wireless device may perform step 2414 based on (e.g., in response to, upon, or after): the first cell being the same as the second cell; determining that the first cell is the same as the second cell; the condition being fulfilled while the RA procedure is ongoing; determining the condition to be fulfilled while the RA procedure is ongoing.

[0531] In an example, step 2412 may be after step 2408, step 2404, step 2406, and / or step 2402.

[0532] In some aspects, step 2412 may be before step 2408, step 2404, step 2406, and / or step 2402.

[0533] In an example, step 2414 may be after step 2408, step 2404, step 2406, and / or step 2402.

[0534] In some aspects, step 2414 may be before step 2408, step 2406, step 2404, and / or step 2402.

[0535] Step 2412 may comprise stopping the RA procedure; not transmitting a PRACH transmission for the RA procedure; not monitoring RAR corresponding to the PRACH transmission; not starting the window (e.g., RAR window); triggering (e.g., initiating) a (RACH-based or RACH-less) cell switch, e.g., via (e.g., of, for, associated with, corresponding to, or configured for, to, in, or toward) the first candidate cell; transmitting a PRACH transmission via the first candidate cell (e.g., based on a valid TA not being available for the first candidate cell); transmitting a PUSCH transmission (e.g., based on a valid TA being available for the first candidate cell or for a group (e.g., TAG) comprising the first candidate cell), wherein the configuration parameters indicate one or more (UL) resources for the PUSCH transmission; transmitting the PUSCH transmission using or based on the valid TA; and / or applying one or more configuration parameters of the configuration parameters (e.g., applying RRC reconfiguration parameters of the configuration parameters).Docket No.: 24-1257PCT

[0536] Step 2414 may comprise continuing the RA procedure; determining the RA procedure to be complete; completing the RA procedure; successfully completing the RA procedure; transmitting a PRACH transmission for the RA procedure; monitoring the search space, e.g., for an RA response; receiving an RAR corresponding to the PRACH transmission (e.g., an RAR comprising a preamble index associated with or of the PRACH transmission); receiving a (valid) TA of, for, associated with, corresponding to, or configured for the second (or first) candidate cell; transmitting, via the second (or first) candidate cell, a PUSCH transmission using or based on the (valid) TA; transmitting the PUSCH transmission after completing the RA procedure; triggering or initiating a cell switch to the second (or first) candidate cell after or based on completing the RA procedure.

[0537] In an example, the cell switch may be a RACH-based cell switch. In a RACH-based cell switch, a first (e.g., first in time or initial) uplink transmission via a candidate cell (e.g., the first candidate cell or the second candidate cell) may be a PRACH transmission (e.g., signal 2314, message(s) 2106). The wireless device may determine (e.g., trigger or initiate) a RACH-based cell switch based on (e.g., in response to) a (valid) TA not being available for the candidate cell.

[0538] In another example, the cell switch may be a RACH-less cell switch. In a RACH-less cell switch, a first (e.g., first in time or initial) uplink transmission via a candidate cell (e.g., the first candidate cell or the second candidate cell) may be a PUSCH transmission. The wireless device may determine (e.g., trigger or initiate) a RACH-less cell switch based on (e.g., in response to, upon, or after) a (valid) TA being available for the candidate cell. The wireless device may transmit the PUSCH transmission (e.g., signal 2314, message(s) 2106) using the (valid) TA.

[0539] The configuration parameters may comprise one or more configured grant (CG) configurations. The one or more CG configurations may comprise or indicate one or more CGs. The one or more CGs may comprise or indicate the one or more UL resources (as described above). The one or more UL resources may comprise or indicate one or more time resources (e.g., time locations or time domain resources). The one or more UL resources may comprise or indicate one or more frequency resources (e.g., frequency locations or frequency domain resources). The one or more UL resources may comprise or indicate one or more beam-related resources (e.g., TCI states, spatial domain filters, spatial domain transmission filters, spatial filters). The one or more UL resources may comprise or indicate one or more power control parameters. The wireless device may determine a transmit power based on or using the one or more power control parameters. The wireless device may transmit the PUSCH transmission using or with the transmit power.

[0540] In an example, signal 2314 may be or comprise the PUSCH transmission. Signal 2314 may comprise or be the same as, for example, message(s) 2106.Docket No.: 24-1257PCT

[0541] In some aspects, the example of FIG. 24 may be performed without one or more of: step 2402, step 2404, step 2406, step 2408, step 2412, and / or step 2414.

[0542] The first candidate cell may be cell 2310, cell 2320, and / or cell 2330.

[0543] The second candidate cell may be cell 2310, cell 2320, and / or cell 2330.

[0544] FIG. 25 illustrates an example flowchart as per an aspect of an embodiment of the present disclosure. The example of FIG. 25 may be used together with or independently from any of the previous examples (e.g., in FIGs. 1A-24).

[0545] According to the example of FIG. 25, at step 2502, a wireless device (e.g., wireless device 2300, wireless device 2200) receives configuration parameters. For example, configuration(s) 2302 may comprise or indicate the configuration parameters. The wireless device may receive the configuration parameters via a serving cell (e.g., cell 2310). The configuration parameters may be for (e.g., of, for, associated with, corresponding to, or configured for) a conditional mobility procedure. The configuration parameters may be of, for, associated with, corresponding to, or configured for a candidate cell (e.g., cell 2330, cell 2320) of the one or more candidate / target cells. The configuration parameters may comprise or indicate a condition (e.g , condition(s) 2312) to switch to the candidate cell (e.g., cell 2330, cell 2320).

[0546] For brevity, the example of FIG. 25 refers to condition(s) 2312 as the condition. It is to be understood that the condition may be replaced with (or comprise) the one or more conditions (e.g., as described above in any of the previous examples). The condition being fulfilled may refer to or be replaced with each (or at least one) of the one or more conditions being fulfilled.

[0547] At step 2504, the wireless device receives a PDCCH order (e.g., signal 2304). The wireless device may receive the PDCCH order via the serving cell (e.g., cell 2310). The PDCCH order may indicate (e.g., initiate or trigger) an RA procedure (e.g., RA procedure 2308, RA procedure 2208). The RA procedure may be for early uplink synchronization (e.g., early sync 2002, early sync 1716), e.g., via the candidate cell. The RA procedure may be via (e.g., of, for, associated with, corresponding to, or configured for) the candidate cell (e.g., cell 2320, cell 2330).

[0548] The PDCCH order may indicate a first RS, e.g., for the RA procedure. For example, the SS / PBCH index field may indicate the first RS (as described previously).

[0549] In some aspects, an RS may be or be replaced with, for example, an SSB, a CSI-RS, an SRS, a positioning SRS, a CRS, and / or any other RS.

[0550] The PDCCH order may indicate (e.g., trigger or initiate) a PRACH transmission, e.g., for the RA procedure. The wireless device may transmit the PRACH transmission via (e.g., using, on, of, for, associated with, corresponding to, or configured for, in, to, toward) one or more resources (e.g., PRACH occasions). The wireless device may determine the one or more resources using the first RS. For example, the configuration parameters may indicate an association (e.g., a mapping or a number of PRACHDocket No.: 24-1257PCT occasions per RS). The wireless device may use the association to determine the one or more resources of, for, associated with, corresponding to, or configured for the first RS. In an example, the configuration parameters may comprise or indicate one or more RSs. The one or more RSs may comprise the first RS.

[0551] The wireless device may transmit the PRACH transmission using or with a transmit power. In some aspects, transmit power may be referred to as transmission power. The wireless device may determine the transmit power based on or using the first RS. For example, the wireless device may determine the transmit power based on or using a pathloss value. The wireless device may determine the pathloss value based on or by measuring the first RS.

[0552] In an example, step 2504 may be after step 2502.

[0553] In some aspects, step 2504 may be before step 2502

[0554] At step 2506, the wireless device may determine the condition (e.g., condition(s) 2312) to be fulfilled. The wireless device may determine the condition to be fulfilled while (e.g., when or during) the RA procedure is ongoing. The RA procedure may be ongoing, for example, based on (e.g., in response to, during, at, after): receiving the PDCCH order; the PDCCH order indicating a PRACH transmission for the RA procedure; determining (e.g., selecting) one or more resources for the PRACH transmission; transmitting the PRACH transmission; monitoring a search space (e.g., common search space, Type-1 CSS, UE-dedicated search space (USS), and / or any other type of search space); monitoring the search space for a response (e.g., RAR, MAC CE, RA response corresponding to the PRACH transmission, RA response comprising a preamble index of, for, associated with, corresponding to, or configured for the PRACH transmission); starting a window (e.g., RA response window) in response to transmitting the PRACH transmission; and / or the window running.

[0555] At step 2506, the wireless device may determine the condition to be fulfilled by using a second RS. For example, the configuration parameters may indicate the second RS. The one or more RSs may comprise the second RS. The wireless device may determine (e.g , select) the RS, from the one or more RSs, to determine whether the condition is fulfilled.

[0556] Using an RS (e.g., the second RS) to determine whether a condition (e.g., the condition, condition(s) 2312, or the one or more conditions) is fulfilled may comprise determining whether the condition is fulfilled based on or using a radio link quality of the RS.

[0557] The radio link quality may comprise reference signal received power (RSRP), signal to noise ratio (SNR), signal to interference plus noise ratio (SINR), reference signal received quality (RSRQ), received signal strength indication or indicator (RSSI), block error rate (BLER), bit error rate (BER), symbol error rate (SER), and / or a combination thereof.

[0558] In an example, the condition may be or comprise the second condition as described above (e.g., determining whether the candidate cell (which may also be referred to as a candidate configuration) isDocket No.: 24-1257PCT better than the threshold) Determining whether the condition is fulfilled may comprise determining whether the radio link quality is better (e.g ., higher, larger, above, more) than the threshold. The condition may be fulfilled based on the radio link quality being better than the threshold. The condition may not be fulfilled based on the radio link quality not being better than (e.g., being worse, lower, or below) the threshold. For brevity, determining whether the condition is fulfilled using the second RS for other conditions, of the one or more conditions, are not described. It is to be understood that any of the one or more conditions may be the condition. The second RS may be used to determine whether the one or more conditions are fulfilled in a same manner.

[0559] At step 2506, the wireless device may determine the condition to be fulfilled, e.g., when the RA procedure is ongoing.

[0560] Step 2506 may be after step 2502 and / or step 2504.

[0561] In some aspects, step 2506 may be before step 2502 and / or step 2504.

[0562] At step 2508, the wireless device may determine whether to stop or continue the RA procedure (e.g., the ongoing RA procedure) based on whether the first RS is the same as the second RS (that is, based on whether the RS of the ongoing RA procedure is the same as the RS that fulfilled the condition).

[0563] The first RS and the second RS may be of, for, associated with, corresponding to, or configured for the candidate cell. For example, the wireless device may receive the first RS and the second RS via the candidate cell (e.g., cell 2320, cell 2330). The wireless device may receive the PDCCH order via the serving cell.

[0564] In an example, the first RS may be different from the second RS. For example, at step 2508, the wireless device may determine that the first RS is different from the second RS. The wireless device may perform a step 2512 based on (e.g., in response to, upon, or after): the first RS being different from the second RS; determining that the first RS is different from the second RS; the condition being fulfilled while the RA procedure is ongoing; determining the condition to be fulfilled while the RA procedure is ongoing.

[0565] In another example, the first RS may be the same as the second RS. For example, the wireless device may determine that the first RS is the same as the second RS. The wireless device may perform step 2514 based on (e.g., in response to, upon, or after): the first RS being the same as the second RS; determining that the first RS is the same as the second RS; the condition being fulfilled while the RA procedure is ongoing; determining the condition to be fulfilled while the RA procedure is ongoing.

[0566] In an example, step 2512 may be after step 2508, step 2506, step 2504, and / or step 2502.

[0567] In an example, step 2512 may be before step 2508, step 2506, step 2504, and / or step 2502.

[0568] In an example, step 2514 may be after step 2508, step 2506, step 2504, and / or step 2502.

[0569] In an example, step 2514 may be before step 2508, step 2506, step 2504, and / or step 2502.Docket No.: 24-1257PCT

[0570] Step 2512 may be the same as step 2412. Step 2514 may be the same as step 2414. For example, the rest of the steps, e.g., step 2512 and step 2514, may follow the corresponding steps of FIG. 24 (e.g., step 2412 and step 2414) respectively and are not described for brevity.

[0571] FIG. 26 illustrates an example flowchart as per an aspect of an embodiment of the present disclosure. The example of FIG. 26 may be used together with or independently from any of the previous examples (e.g., in FIGs. 1A-25).

[0572] In FIG. 26, at step 2602, the wireless device (e.g., wireless device 2300, wireless device 2200) may receive, via a serving cell, configuration parameters (e.g., configuration(s) 2302) comprising or indicating a condition (e.g., condition(s) 2312) to switch to a candidate cell (e.g., cell 2320, cell 2330). Step 2602 may be the same as step 2502.

[0573] At step 2604, the wireless device may receive a PDCCH order via the serving cell (e.g., cell 2310). The PDCCH order may indicate (e.g., initiate or trigger) an RA procedure via the candidate cell (e.g., cell 2320, cell 2330). The PDCCH order may indicate a first RS for the RA procedure. Step 2604 may be the same as step 2504.

[0574] At step 2606, the wireless device may determine, using a second RS, the condition to be fulfilled, e.g., while the RA procedure is ongoing. Step 2606 may be the same as step 2506. The second RS may be referred to as a candidate RS, candidate beam, candidate cell, and / or candidate RS configuration.

[0575] At step 2608, the wireless device may determine whether to stop or continue the RA procedure (e.g , the ongoing RA procedure) based on whether a first radio link quality of the first RS is above (e.g., higher than, greater than, better than, stronger than, or more than) a second radio link quality of the second RS (that is, based on whether the RS of the ongoing procedure is better or stronger than an RS that fulfilled the condition).

[0576] The first RS and the second RS may be of, for, associated with, corresponding to, or configured for the candidate cell. For example, the wireless device may receive the first RS and the second RS via the candidate cell (e.g., cell 2320, cell 2330). The wireless device may receive the PDCCH order via the serving cell.

[0577] In an example, the first radio link quality may not be above the second radio link quality (e.g., may be below (e.g., weaker than, less than, worse than) the second radio link quality). For example, at step 2608, the wireless device may determine that the first radio link quality is not above the second radio link quality (e.g., the first radio link quality is below the second radio link quality). The wireless device may perform a step 2612 based on (e.g., in response to, upon, or after): the first radio link quality being below the second radio link quality; determining that the first radio link quality is below the second radio link quality; the condition being fulfilled while the RA procedure is ongoing; determining the condition to be fulfilled while the RA procedure is ongoing.Docket No.: 24-1257PCT

[0578] In another example, the first radio link quality may be above the second radio link quality. For example, at step 2608, the wireless device may determine that the first radio link quality is above the second radio link quality. The wireless device may perform a step 2614 based on (e.g., in response to, upon, or after): the first radio link quality being above the second radio link quality; determining that the first radio link quality is above the second radio link quality; the condition being fulfilled while the RA procedure is ongoing; determining the condition to be fulfilled while the RA procedure is ongoing.

[0579] In an example, step 2612 may be after (or before) step 2608, step 2606, step 2604, and / or step 2602.

[0580] In an example, step 2614 may be after (or before) step 2608, step 2606, step 2604, and / or step 2602.

[0581] Step 2612 may be the same as step 2512 and / or step 2412. Step 2614 may be the same as step 2514 and / or step 2414. For example, the rest of the steps, e.g., step 2612 and step 2614, may follow the corresponding steps of FIG. 24 and / or FIG. 25 (e.g., step 2412 and / or step 2512 and step 2414 and / or step 2514) respectively and are not described for brevity.

[0582] In an example, the wireless device may determine the condition to be fulfilled using the second RS. In another example, the second RS may be from or among the one or more RSs (e.g., candidate RSs) but may not be the one used to determine the condition to be fulfilled.

[0583] In some aspects, the PDCCH order may indicate whether the RA procedure may be stopped (e.g., whether the wireless device may stop the RA procedure) in response to the condition being fulfilled while the RA procedure is ongoing.

[0584] In an example, the PDCCH order may indicate that the RA procedure may be stopped in response to the condition being fulfilled while the RA procedure is ongoing. The wireless device may perform step 2412, step 2512, and / or step 2612 based on (e.g., in response to, upon, or after): the PDCCH order indicating that the RA procedure may be stopped in response to the condition being fulfilled while the RA procedure is ongoing; the condition being fulfilled while the RA procedure is ongoing; determining the condition to be fulfilled while the RA procedure is ongoing.

[0585] In another example, the PDCCH order may not indicate that the RA procedure may be stopped in response to the condition being fulfilled while the RA procedure is ongoing (or may indicate that the RA procedure may not be stopped in response to the condition being fulfilled while the RA procedure is ongoing). The wireless device may perform step 2414, step 2514, and / or step 2614 based on (e.g., in response to, upon, or after): the PDCCH order not indicating that the RA procedure may be stopped in response to the condition being fulfilled while the RA procedure is ongoing (or indicating that the RA procedure may not be stopped in response to the condition being fulfilled while the RA procedure isDocket No.: 24-1257PCT ongoing); the condition being fulfilled while the RA procedure is ongoing; determining the condition to be fulfilled while the RA procedure is ongoing.

[0586] In some aspects, the RA procedure may be performed via the serving cell. For example, the PDCCH order may indicate the RA procedure for the serving cell. The RA procedure may be triggered by one or more events. At step 2408, step 2508, and / or step 2608, the wireless device may determine whether to stop the RA procedure or continue the RA procedure based on the one or more events. For example, the wireless device may perform step 2412, step 2512, and / or step 2612 based on (e.g., in response to, upon, or after): the RA procedure being triggered by (e.g., initiated by, of, for, associated with, corresponding to, or configured for) the one or more events; the condition being fulfilled while the RA procedure is ongoing; determining the condition to be fulfilled while the RA procedure is ongoing.

[0587] The wireless device may perform step 2414, step 2514, and / or step 2614 based on (e.g., in response to, upon, or after): the RA procedure being triggered by (e.g., initiated by, of, for, associated with, corresponding to, or configured for) the one or more events; the condition being fulfilled while the RA procedure is ongoing; determining the condition to be fulfilled while the RA procedure is ongoing.

[0588] The one or more events may comprise: Initial access from RRCJDLE mode or state; RRC Connection Re-establishment procedure; DL or UL data arrival, during RRCJDONNECTED or during RRCJNACTIVE while small data transmission (SDT) procedure is ongoing, when UL synchronization status is "non-synchronized"; UL data arrival, during RRC_CONNECTED or during RRCJNACTIVE while SDT procedure is ongoing, when there are no PUCCH resources for SR available; Handover, except for when RACH-less HO is configured; SR failure; Explicit request by RRC (e.g., RRC layer of the wireless device) upon synchronous reconfiguration (e.g., reconfiguration-with-sync)’, RRC Connection Resume procedure from RRCJNACTIVE mode or state; To establish time alignment for a primary or a secondary TAG; Request for Other SI; Beam failure recovery; Consistent UL LBT failure on SpCell; SDT in RRCJNACTIVE; Positioning purpose during RRC_CONNECTED mode or state requiring the RA procedure, e.g., when timing advance is needed for wireless device positioning; Early UL synchronization with the candidate cell; and / or RACH-based cell switch.

[0589] In an example, a wireless device may transmit a PRACH transmission (e.g., signal 2314) for a RACH-based cell switch. The wireless device may transmit the PRACH transmission for a first RA procedure. The first RA procedure may be different from last or previous RA procedure. In existing technologies, when the wireless device initiates a new RA procedure (e.g., the first RA procedure), the wireless device resets a counter (e.g., preamble transmission counter or power ramping counter). This may be suitable for scenarios not involving a cell switch as it allows the wireless device to start the new RA procedure afresh. However, this results in the wireless device starting from a lower transmit power, whichDocket No.: 24-1257PCT may result in PRACH transmission failures when the channel conditions are poor (e.g., high attenuation or high noise scenarios that may be more common in mobility conditions).

[0590] A possible solution to solve the above problem is to not reset the counter when the first RA procedure is for a cell switch. However, this may result in the wireless device using an excessively high transmit power (e.g., due to high transmit power used for a previous or last RA procedure via a cell with poor channel conditions). This may result in high network interference, high power consumption, and / or decrease in battery life of the wireless device.

[0591] In light of the existing technologies, there is a need to solve transmission power design when perform an RA procedure for or during cell switch of or for a conditional mobility procedure.

[0592] Example embodiments may solve the problems described above. In an example embodiment, a wireless device initializes (e.g., set to 1) the counter based on (e.g., in response to, upon, or after): the new RA procedure being for RACH-based cell switch, the candidate cell being different from the candidate cell of the last or previous RA procedure, and / or the RS (e.g., SSB) used for the new RA procedure and the last or previous RA procedure being different. The wireless device does not initialize the counter based on (e.g., in response to, upon, or after): the new RA procedure being for RACH-based cell-switch, the candidate cell being the same as the candidate cell of, for, associated with, corresponding to, or configured for the last or previous RA procedure, and / or the RS (e.g., SSB) used for the new RA procedure and the last or previous RA procedure being the same.

[0593] Using the example embodiments, mobility interruption time and / or latency may be reduced by identifying that the previous RA procedure and the new RA procedure (for RACH-based cell switch) are of, for, associated with, corresponding to, or configured for the same candidate cell and / or the same RS.

[0594] In some aspects, resetting a counter may be the same as initializing or re-initializing the counter.

[0595] FIG. 27 shows an example flowchart as per an aspect of an embodiment of the present disclosure. The example of FIG. 27 may be used together with or independently from any of the previous examples (e.g., in FIGs. 1A-26).

[0596] In the example of FIG. 27, at step 2702, a wireless device (e.g., wireless device 2300, wireless device 2200) performs a first RA procedure (e.g., RA procedure 2208, RA procedure 2308). The wireless device may perform the first RA procedure via (e g., of, for, associated with, corresponding to, or configured for, on, in, to, toward) a first cell (e.g., cell 2320, cell 2330). The wireless device may use a first RS for the first RA procedure.

[0597] Performing aa RA procedure (e.g., the RA procedure, RA procedure 2208, RA procedure 2308) may comprise: determining (e.g., selecting) an RS, of the one or more RSs, for the RA procedure; determining one or more resources (e.g., PRACH occasions) for a PRACH transmission (e.g., signal 2004, signal 2306, signal 2206, signal 2314) based on the one or more RSs (using the techniques describedDocket No.: 24-1257PCT above); transmitting the PRACH transmission; monitoring a search space (e.g., CSS, type-1 CSS, USS) for a response (e.g., RAR, MAC CE, signal 2006) in response to the PRACH transmission; and / or receiving the response.

[0598] The wireless device may transmit a PRACH transmission (e.g., signal 2306) for the first RA procedure. The wireless device may transmit the PRACH transmission via one or more resources (e.g., PRACH occasions). The wireless device may transmit the PRACH transmission with or using a transmit power. The wireless device may determine the one or more resources based on the first RS (e.g., based on an association or mapping between the first RS and the one or more resources using the techniques described above). The wireless device may determine the transmit power based on a pathloss, wherein the pathloss is determined based on measuring the first RS. The wireless device may transmit the PRACH transmission via the first cell. The wireless device may receive the first RS via the first cell. The first cell may be a candidate / target cell of the one or more candidate / target cells.

[0599] At step 2704, the wireless device stops the first RA procedure. For example, the wireless device may stop the RA procedure based on a condition for cell switch being fulfilled. In an example, at step 2704, the wireless device may stop the first RA procedure based on or by performing step 2412, step 2512, and / or step 2612.

[0600] At step 2706, the wireless device may trigger a second RA procedure. Step 2706 may be after step 2702 and / or step 2704.

[0601] The second RA procedure may be of, for, associated with, corresponding to, or configured for RACH-based cell switch (e.g., LTM cell switch). In some aspects, cell switch may be replaced with or refer to LTM cell switch or a cell switch procedure.

[0602] The second RA procedure may be of, for, associated with, corresponding to, or configured for a second cell (e.g., cell 2320, cell 2330). The one or more candidate / target cells may comprise the second cell. The wireless device may use a second RS for the second RA procedure. The wireless device may use the second RS for the second RA procedure as described above in the context of using the first RS for the first RA procedure.

[0603] At step 2708, the wireless device may determine whether the first RS is the same as the second RS. In an example, the first RS may not be the same as the second RS (e.g., the first RS may be different from the second RS). The wireless device may perform step 2712 based on the first RS not being the same as the second RS (or the first RS being different from the second RS).

[0604] In another example, the first RS may be the same as the second RS. The wireless device may perform step 2714 based on the first RS being different from the second RS. At step 2714, the wireless device may determine whether the first cell is the same as the second cell. In an example, the first cell may not be the same as the second cell (or different from the second cell). The wireless device may performDocket No.: 24-1257PCT step 2712 based on the first cell not being the same as the second cell (or being different from the second cell).

[0605] In another example, the first cell may be the same as the second cell. The wireless device may perform step 2716 based on the first cell being the same as the second cell.

[0606] The wireless device may perform step 2716 based on (e.g., in response to, upon, or after): triggering the second RA procedure; the second RA procedure being for RACH-based cell switch; the first RA procedure being a last or previous RA procedure of or for the second RA procedure; the condition being fulfilled; stopping the first RA procedure, e.g., based on the condition being fulfilled; the first RS (used for the first RA procedure) being the same as the second RS; and / or the first cell being the same as the second cell.

[0607] The wireless device may perform step 2712 based on (e.g., in response to, upon, or after): triggering the second RA procedure; the second RA procedure being for RACH-based cell switch; the first RA procedure being a last or previous RA procedure of or for the second RA procedure; the condition being fulfilled; stopping the first RA procedure, e.g., based on the condition being fulfilled; the first RS (used for the first RA procedure) not being the same as (or being different from) the second RS; and / or the first cell not being the same as (or being different from) the second cell.

[0608] Step 2712 may comprise the wireless device initializing (e.g., reinitializing or resetting) a counter. The counter may be a preamble transmission counter. The counter may be a power ramping counter. The power ramping counter may be referred to as a preamble power ramping counter.

[0609] The preamble transmission counter may count a number of PRACH transmissions. Based on (e.g., in response to, upon, or after) the preamble transmission counter reaching a threshold, the wireless device may determine a failure of an RA procedure. Determining the failure of the RA procedure may comprise: completing the RA procedure; and / or indicating a failure of the RA procedure to the base station (e.g., transmitting a signal, e.g., signal 2314, indicating a failure of the RA procedure). In an example, the configuration parameters may comprise or indicate the threshold.

[0610] The power ramping counter may be used by the wireless device to determine a transmit power. Initializing the counter may comprise setting the counter to a first value. The first value may be 0, 1 , 2, 3... . For example, the wireless device may determine the transmit power based on (a value of) the power ramping counter. The wireless device may transmit the PRACH transmission using or with the transmit power.

[0611] Step 2716 may comprise the wireless device not initializing the counter (e.g., maintaining or keeping the same the counter). Not initializing the counter may comprise not incrementing the counter, not decrementing the counter, not setting the counter to 1 , maintaining the same or previous value of the counter, and / or fixing the value of the counter.Docket No.: 24-1257PCT

[0612] Step 2712 and / or step 2716 may comprise: transmitting a PRACH transmission (e.g., signal 2314) for the second RA procedure; transmitting the PRACH transmission via the second cell (e.g., candidate cell, cell 2320, cell 2330); determining a transmit power based on the counter or based on a value of the counter; transmitting the PRACH transmission using or with the transmit power.

[0613] In some aspects, triggering an RA procedure (e.g., the first RA procedure, the second RA procedure, RA procedure 2308, RA procedure 2208) may refer to initiating, performing, completing, successfully completing, and / or ending the RA procedure.

[0614] In some aspects, switching cells may referred to as cell switch (or cell switch procedure), performing cell switch, and / or executing cell switch.

[0615] If the condition is fulfilled for a candidate cell, if there is an ongoing RA procedure, if the RA procedure is for early uplink synchronization with the candidate cell, continue the ongoing RA procedure and / or perform or execute cell switch after the ongoing RA procedure is completed; else (if the RA procedure is not for the candidate cell), stop or abort the ongoing RA procedure and execute cell switch to the candidate cell.

[0616] In some aspects, the techniques described herein relate to a method comprising: receiving, by a wireless device and via a serving cell, configuration parameters of candidate cells of a conditional layer 1 or layer 2 triggered mobility (LTM) procedure, wherein the configuration parameters indicate a condition to switch to a first candidate cell of the candidate cells; receiving a physical downlink control channel (PDCCH) order indicating a first RA preamble, for an RA procedure, to transmit via a second candidate cell of the candidate cells; stopping or aborting the RA procedure based on: the condition being satisfied while the RA procedure is ongoing; and the first candidate cell being different from the second candidate cell; and transmitting, via the first candidate cell and after switching to the first candidate cell, an uplink transmission.

[0617] In some aspects, the techniques described herein relate to a method comprising: transmitting, via a second candidate cell of candidate cells, an RA preamble of an RA procedure for cell switch; and stopping or aborting the RA procedure based on: determining to switch to a first candidate cell, of the candidate cells, while the RA procedure is ongoing; and the first candidate cell being different from the second candidate cell.

[0618] In some aspects, the techniques described herein relate to a method, further comprising receiving configuration parameters of the candidate cells.

[0619] In some aspects, the techniques described herein relate to a method, wherein the candidate cells are of a conditional LTM procedure.

[0620] In some aspects, the techniques described herein relate to a method, wherein the configuration parameters indicate a condition to switch to the first candidate cellDocket No.: 24-1257PCT

[0621] In some aspects, the techniques described herein relate to a method, further comprising receiving a PDCCH order, wherein the PDCCH order: initiates the RA procedure; indicates the RA preamble; and / or indicates the second candidate cell for transmitting the RA preamble.

[0622] In some aspects, the techniques described herein relate to a method, further comprising transmitting, via the first candidate cell and after switching to the first candidate cell, an uplink transmission.

[0623] In some aspects, the techniques described herein relate to a method, wherein the uplink transmission is a PUSCH transmission based on determining a TA value of the first candidate cell prior to switching to the first candidate cell.

[0624] In some aspects, the techniques described herein relate to a method, wherein the configuration parameters indicate one or more resources for the PUSCH transmission.

[0625] In some aspects, the techniques described herein relate to a method, wherein the uplink transmission is via the one or more resources.

[0626] In some aspects, the techniques described herein relate to a method, wherein the uplink transmission is a PRACH transmission based on not determining a TA value of the first candidate cell prior to switching to the first candidate cell.

[0627] In some aspects, the techniques described herein relate to a method, wherein the configuration parameters indicate one or more PRACH resources for the PRACH transmission.

[0628] In some aspects, the techniques described herein relate to a method, wherein the uplink transmission is via the one or more PRACH resources.

[0629] In some aspects, the techniques described herein relate to a method, wherein the RA procedure is for early uplink synchronization via the first candidate cell.

[0630] In some aspects, the techniques described herein relate to a method, wherein stopping the RA procedure includes at least one of: ending the RA procedure; aborting the RA procedure; not transmitting an RA preamble for the RA procedure; and / or not monitoring for an RA response.

[0631] In some aspects, the techniques described herein relate to a method, further comprising continuing a second RA procedure based on: determining to switch to a third candidate cell, of the candidate cells, while the second RA procedure is ongoing; and the third candidate cell being same as the second candidate cell.

[0632] In some aspects, the techniques described herein relate to a method comprising: transmitting, via a candidate cell of candidate cells, an RA preamble of an RA procedure for cell switch; and continuing the RA procedure based on: determining to switch to a first candidate cell, of the candidate cells, while the RA procedure is ongoing; and the first candidate cell being same as the candidate cell.

[0633] In some aspects, the techniques described herein relate to a method comprising: receiving, by a wireless device and via a serving cell, configuration parameters of a candidate cell for conditional layer 1 orDocket No.: 24-1257PCT layer 2 triggered mobility (LTM) procedure, wherein the configuration parameters indicate one or more conditions to switch to the candidate cell; receiving a physical downlink control channel (PDCCH) order indicating: an RA preamble transmission, for an RA procedure, via the candidate cell; and a first RS for the RA preamble transmission; determining, using a second RS, at least one of the one or more conditions to be satisfied; in response to the determining, stopping the RA procedure based on a first radio link quality, of the first RS, being worse than a second radio link quality of the second RS; and transmitting, via the candidate cell and after cell switch to the candidate cell, a second RA preamble.

[0634] FIG. 28 illustrates an example signal flow diagram as per an aspect of an embodiment of the present disclosure. The example of FIG. 28 may be used together with or independently from any of the previous examples (e.g., in FIGs. 1A-27).

[0635] In the example of FIG. 28, a wireless device 2800 receives configuration(s) 2802 via a cell 2810. Wireless device 2800 may be the same as wireless device 2300 and / or wireless device 2200.Configuration(s) 2802 may be the same as configuration(s) 2302. Cell 2810 may be the same as cell 2310.

[0636] Configuration(s) 2802 may comprise or indicate the one or more candidate / target (LTM cell) configurations of or for the one or more candidate / target cells. The one or more candidate / target cells may comprise a cell 2820.

[0637] In an example, wireless device 2800 receives a signal 2804. Signal 2804 may be the same as signal 2304. Signal 2804 may comprise or be a PDCCH order. Signal 2804 may indicate (e.g., initiate or trigger) an RA procedure. Signal 2804 may indicate a signal 2806. Signal 2806 may be the same as signal 2306. Signal 2806 may be or comprise a PRACH transmission.

[0638] Wireless device 2800 may transmit signal 2806 for early uplink synchronization (e.g., early sync 2002, early sync 1716). The RA procedure may be of, for, associated with, corresponding...

Claims

Docket No.: 24-1257PCTCLAIMSWhat is claimed is:

1. A method comprising: receiving, by a wireless device and via a serving cell, configuration parameters of candidate cells of a conditional layer 1 or 2 triggered mobility (LTM) procedure, wherein the configuration parameters: comprise one or more configured grant (CG) configurations indicating one or more time resources for physical uplink shared channel (PUSCH) transmission via a candidate cell of the candidate cells; and indicate one or more conditions to switch to the candidate cell; receiving, via the serving cell, a physical downlink control channel (PDCCH) order initiating a random-access (RA) procedure, wherein the PDCCH order indicates an RA preamble to transmit, for the RA procedure, via the candidate cell; completing the RA procedure in response to transmitting the RA preamble; receiving, after transmitting the RA preamble, an LTM timing advance command (TAC) medium access control (MAC) control element (CE) comprising a TAC indicating a first timing advance (TA) value of the candidate cell; determining the one or more conditions to switch to the candidate cell to be satisfied; and in response to the determining, performing an RA channel (RACH)-less conditional LTM cell switch based on successfully measuring a second TA value for the candidate cell, wherein the RACH-less conditional LTM cell switch comprises transmitting, via the candidate cell and a time resource of the one or more time resources, a PUSCH transmission using the second TA value.

2. A method comprising: receiving, by a wireless device, a layer 1 or 2 triggered mobility (LTM) timing advance command (TAC) medium access control (MAC) control element (CE) comprising a TAC indicating a first timing advance (TA) value of a candidate cell of candidate cells of a conditional LTM procedure; determining one or more conditions to switch to the candidate cell to be satisfied; and in response to the determining, performing a random access (RA) channel (RACH)-less conditional LTM cell switch based on successfully measuring a second TA value for the candidate cell, wherein the RACH-less conditional LTM cell switch comprises transmitting, via the candidate cell, a physical uplink shared channel (PUSCH) transmission using the second TA value.

3. The method of claim 2, further comprising receiving, via a serving cell, configuration parameters of the candidate cells, wherein the configuration parameters:Docket No.: 24-1257PCT comprise one or more configured grant (CG) configurations indicating one or more time resources for PUSCH transmission via a candidate cell of the candidate cells; and indicate the one or more conditions to switch to the candidate cell.

4. The method of claim 3, wherein the PUSCH transmission is transmitted via the one or more time resources.

5. The method of any one of claims 2 to 4, further comprising receiving, via a serving cell, a physical downlink control channel (PDCCH) order initiating an RA procedure, wherein the PDCCH order indicates an RA preamble to transmit, for the RA procedure, via the candidate cell;6. The method of claim 5, further comprising completing the RA procedure in response to transmitting the RA preamble.

7. The method of any one of claims 1 to 6, further comprising receiving a second PDCCH order initiating a second RA procedure.

8. The method of claim 7, wherein the second PDCCH order indicates a second RA preamble to transmit via a second candidate cell of the candidate cells.

9. The method of claim 8, further comprising transmitting the second RA preamble via the second candidate cell.

10. The method of claim 9, further comprising completing the RA procedure in response to transmitting the second RA preamble.11 . The method of any one of claims 1 to 10, wherein successfully measuring the second TA value for the candidate cell comprises measuring the second TA value using a user equipment (UE)-based TA measurement procedure.

12. The method of claim 11 , further comprising the configuration parameters indicating the UE-based TA measurement procedure.

13. The method of claim 12, wherein the configuration parameters comprise: a first parameter; and a second parameter.

14. The method of claim 13, wherein: the first parameter indicates an index of the UE-based TA measurement procedure; and the second parameter indicates an index of a serving cell for UE-based TA measurement procedure.

15. The method of claim 13 or 14, wherein: the first parameter is set to a first value; and the second parameter is set to the first value.Docket No.: 24-1257PCT16. The method of claim 15, wherein the configuration parameters indicate that the wireless device is enabled to perform the UE-based TA measurement procedure based on the first parameter and the second parameter both being set to a same value.

17. The method of any one of claims 1 to 16, further comprising starting a time alignment timer associated with the candidate cell.

18. A method comprising: receiving, by a wireless device and via a serving cell, configuration parameters of candidate cells of a conditional layer 1 or 2 triggered mobility (LTM) procedure, wherein the configuration parameters indicate a condition to switch to a first cell of the candidate cells; receiving, via the serving cell, a physical downlink control channel (PDCCH) order indicating a random-access (RA) preamble, for an RA procedure, to transmit via a second cell of the candidate cells; stopping the RA procedure based on the condition being satisfied while the RA procedure is ongoing; and transmitting, via the first cell and after switching to the first cell, an uplink transmission.

19. A method comprising: initiating, by a wireless device, a random-access (RA) procedure for a second cell; and stopping the RA procedure based on determining to switch to a first cell while the RA procedure is ongoing, wherein: the determining is based on a condition being satisfied; and the first cell is a candidate cell of a conditional layer 1 or 2 triggered mobility (LTM) procedure.

20. The method of claim 19, further comprising receiving, via a serving cell, configuration parameters of candidate cells of a conditional layer 1 or 2 triggered mobility (LTM) procedure, wherein the configuration parameters indicate the condition to switch to a first cell of the candidate cells.21 . The method of claim 20, further comprising receiving, via the serving cell, a physical downlink control channel (PDCCH) order indicating a random-access (RA) preamble, for an RA procedure, to transmit via the second cell.

22. The method of claim 21 , wherein the candidate cells comprise the second cell.

23. The method of claim 22, further comprising transmitting, via the first cell and after switching to the first cell, an uplink transmission.

24. The method of any one of claims 18 to 23, wherein the PDCCH order: initiates the RA procedure; and indicates the second cell for transmitting the RA preamble.Docket No.: 24-1257PCT25. The method of any one of claims 18 to 24, wherein the uplink transmission is a physical uplink shared channel (PUSCH) transmission based on determining a timing advance (TA) value of the first cell prior to switching to the first cell.

26. The method of claim 25, wherein the configuration parameters indicate one or more resources for the PUSCH transmission.

27. The method of claim 26, wherein the uplink transmission is via the one or more resources.

28. The method of any one of claims 18 to 24, wherein the uplink transmission in a physical randomaccess channel (PRACH) transmission based on not determining a TA value of the first cell prior to switching to the first cell.

29. The method of claim 28, wherein the configuration parameters indicate one or more PRACH resources for the PRACH transmission.

30. The method of claim 29, wherein the uplink transmission is via the one or more PRACH resources.

31. The method of any one of claims 18 to 30, wherein the RA procedure is for early uplink synchronization of or via the first cell.

32. A method comprising: receiving, by a wireless device and via a serving cell, configuration parameters of a candidate cell of a conditional layer 1 or 2 triggered mobility (LTM) procedure, wherein the configuration parameters indicate a timer used to monitor for timing advance value; receiving, via the serving cell, a physical downlink control channel (PDCCH) order indicating a physical random-access channel (PRACH) transmission via the candidate cell; starting the timer in response to transmitting the PRACH transmission; and transmitting, via the candidate cell, an uplink transmission after starting the timer.

33. The method of claim 32, further comprising monitoring for a medium access control (MAC) control element (CE) while the timer is running.

34. The method of claim 33, wherein the PRACH transmission is for a random-access procedure.

35. The method of claim 34, wherein the PDCCH order initiates the random-access procedure.

36. The method of claim 35, further comprising completing the random-access procedure after transmitting the PRACH transmission37. The method of claim 36, further comprising stopping the timer based on receiving a MAC CE comprising a timing advance value of the candidate cell.

38. An apparatus comprising: one or more processors; and memory storing instructions that, when executed by the one or more processors, cause the apparatus to perform the method of any one of claims 1 to 37.Docket No.: 24-1257PCT39. A non-transitory computer-readable medium comprising instructions that, when executed by one or more processors of an apparatus, cause the apparatus to perform the method of any one of claims 1 to 37.

40. A system comprising: a base station; and a wireless device comprising one or more processors and memory storing instructions that, when executed by the one or more processors, cause the wireless device to perform the method of any one of claims 1 to 37.

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