Method and System for Logical Channel Configuration

Abstract

A wireless device receives one or more radio resource control (RRC) messages from a base station, the RRC messages including a logical channel configuration for a logical channel, the logical channel configuration being configured for transmission of data of the logical channel in an RRC inactive state or an RRC idle state.

Description

[0001] Cross - Reference to Related Applications

[0002] This application claims priority to U.S. Provisional Application No. 63 / 134,064, filed on January 5, 2021, which is hereby incorporated by reference in its entirety. BRIEF DESCRIPTION OF THE DRAWINGS

[0003] Examples of several embodiments of the present disclosure are described herein with reference to the drawings.

[0004] Figure 1A and Figure 1B show an exemplary mobile communication network in which embodiments of the present disclosure can be implemented.

[0005] Figure 2A and Figure 2B show a New Radio (NR) user plane and control plane protocol stack, respectively.

[0006] Figure 3 show an example of services provided between protocol layers of the NR user plane protocol stack in Figure 2A ...

[0007] Figure 4A show an exemplary downlink data stream flowing through Figure 2A the NR user plane protocol stack.

[0008] Figure 4B show an exemplary format of a MAC sub - header in a MAC PDU.

[0009] Figure 5A and Figure 5B show the mapping between logical channels, transport channels, and physical channels for downlink and uplink, respectively.

[0010] Figure 6 is an example diagram showing the RRC state transition of a UE.

[0011] Figure 7 show an exemplary configuration of an NR frame into which OFDM symbols are grouped.

[0012] Figure 8 show an exemplary configuration of time slots in the time and frequency domains of an NR carrier.

[0013] Figure 9 show an example of bandwidth adaptation using three configured Bandwidth Parts (BWPs) of an NR carrier.

[0014] Figure 10A show three carrier aggregation configurations with two component carriers.

[0015] Figure 10B Shows an example of how an aggregated cell can be configured into one or more PUCCH groups.

[0016] Figure 11A Shows an example of the SS / PBCH block structure and location.

[0017] Figure 11B Shows an example of CSI-RS mapped in the time and frequency domains.

[0018] Figure 12A and Figure 12B Show examples of three downlink and uplink beam management procedures, respectively.

[0019] Figure 13A 、 Figure 13B and Figure 13C Show a four-step contention-based random access procedure, a two-step contention-free random access procedure, and another two-step random access procedure, respectively.

[0020] Figure 14A Shows an example of CORESET configuration of a bandwidth part.

[0021] Figure 14B Shows an example of the CCE-to-REG mapping for DCI transmission in CORESET and PDCCH processing.

[0022] Figure 15 Shows an example of a wireless device communicating with a base station.

[0023] Figure 16A 、 Figure 16B 、 Figure 16C and Figure 16D Show exemplary structures for uplink and downlink transmissions.

[0024] Figure 17 Shows an example of an RRC connection reestablishment procedure.

[0025] Figure 18 Shows an example of an RRC connection resume procedure.

[0026] Figure 19 Shows an example of small data transmission.

[0027] Figure 20 Shows an example of early data transmission (EDT).

[0028] Figure 21 Shows an example diagram of small data transmission using preconfigured uplink resources.

[0029] Figure 22 Shows an example of the logical channel information of small data transmission.

[0030] Figure 23 Shows an example of logical channel information for small data transmission.

[0031] Figure 24 Shows an example of logical channel information for small data transmission in the RRC inactive state.

[0032] Figure 25 Shows an example of logical channel information for small data transmission in the RRC connected state.

[0033] Figure 26 Shows an example of logical channel information for small data transmission in a base station including a CU (Central Unit) and a DU (Distributed Unit).

[0034] Figure 27A Shows a first example of information on logical channels configured for small data transmission.

[0035] Figure 27B Shows a second example of information on logical channels configured for small data transmission. Detailed implementation

[0036] In the present disclosure, various embodiments are presented in the form of examples of how the disclosed technology can be implemented and / or how the disclosed technology can be practiced in an environment and scenario. It will be apparent to those skilled in the relevant art that various changes can be made in form and detail without departing from the scope of the present invention. In fact, after reading the specification, it will be apparent to those skilled in the relevant art how to implement alternative embodiments. The embodiments of the present invention 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 exemplary embodiments can be combined to create additional embodiments within the scope of the present disclosure. Any figures highlighting functionality and advantages are given for illustrative purposes only. The disclosed architecture is flexible and configurable enough such that it can be utilized in a manner different from the shown manner. For example, the actions listed in any flowchart can be reordered or used only optionally in certain embodiments.

[0037] Embodiments can be configured to operate as needed. For example, in a wireless device, a base station, a radio environment, a network, a combination of the above, etc., when certain criteria are met, the disclosed mechanisms can be executed. Exemplary criteria can be at least partially based on, for example, wireless device or network node configuration, traffic load, initial system settings, packet size, traffic characteristics, a combination of the above, etc. When one or more criteria are met, various exemplary embodiments can be applied. Thus, exemplary embodiments of selectively implementing the disclosed protocol can be implemented.

[0038] A base station can communicate with a mixture of wireless devices. The wireless devices and / or the base station can support multiple technologies and / or multiple versions of the same technology. The wireless devices may have certain specific capabilities, depending on the wireless device category and / or capabilities. When this disclosure refers to a base station communicating with multiple wireless devices, this disclosure may mean a subset of the total wireless devices in the coverage area. For example, this disclosure can mean multiple wireless devices with a given capability and a given LTE or 5G version in a given sector of the base station. The multiple wireless devices in this disclosure can refer to a selected multiple of wireless devices, and / or a subset of the total wireless devices in the coverage area that execute according to the disclosed method, etc. There may be multiple base stations or multiple wireless devices in the coverage area that may not conform to the disclosed method. For example, these wireless devices or base stations may execute based on an older version of LTE or 5G technology.

[0039] In this disclosure, "a", "an", and similar phrases will be interpreted as "at least one" and "one or more". Similarly, any term ending with the suffix "(s)" will be interpreted as "at least one" and "one or more". In this disclosure, the term "may" is interpreted as "may, for example". In other words, the term "may" indicates that the phrase after the term "may" is an example of one of the multiple suitable possibilities that may or may not be used in one or more of the various embodiments. As used herein, the terms "comprising" and "consisting of" enumerate one or more components of the element being described. The term "comprising" is interchangeable with "including" and does not exclude components not enumerated from being included in the element being described. In contrast, "consisting of" provides a complete enumeration of the one or more components of the element being described. As used herein, the term "based on" should be interpreted as "at least partially based on" rather than, for example, "only based on". As used herein, the term "and / or" represents any possible combination of the enumerated elements. For example, "A, B, and / or C" can represent A; B; C; A and B; A and C; B and C; or A, B, and C.

[0040] If A and B are sets and every element of A is also an element of B, then A is called a subset of B. In this specification, only non-empty sets and subsets are considered. For example, the possible subsets of B = {cell1, cell2} are: {cell1}, {cell2}, and {cell1, cell2}. The phrase "based on" (or equivalently "at least based on") means that the phrase following the term "based on" is an example of one of the various suitable possibilities that may or may not be used in one or more different embodiments. The phrase "responsive to" (or equivalently "at least responsive to") means that the phrase following the term "responsive to" is an example of one of the various suitable possibilities that may or may not be used in one or more different embodiments. The phrase "depending on" (or equivalently "at least depending on") means that the phrase following the term "depending on" is an example of one of the various suitable possibilities that may or may not be used in one or more different embodiments. The phrase "employ / use" (or equivalently "at least employ / use") means that the phrase following the term "employ / use" is an example of one of the various suitable possibilities that may or may not be used in one or more different embodiments.

[0041] The term "configured" can relate to the capabilities of a device, whether the device is in an operating state or a non-operating state. "Configured" can also mean specific settings within the device that affect the operating characteristics of the device, whether the device is in an operating state or a non-operating state. In other words, hardware, software, firmware, registers, memory values, etc. can be "configured" within the device to provide the device with specific characteristics, whether the device is in an operating state or a non-operating state. A term such as "control message induced in a device" can mean that the control message has parameters that can be used to configure specific characteristics in the device or parameters that can be used to implement certain actions in the device, whether the device is in an operating state or a non-operating state.

[0042] In the present disclosure, a parameter (or equivalently referred to as a field or information element: IE) can include one or more information objects, and an information object can include one or more other objects. For example, if parameter (IE) N includes parameter (IE) M, and parameter (IE) M includes parameter (IE) K, and parameter (IE) K includes parameter (information element) J. Then for example, N includes K, and N includes J. In an exemplary embodiment, when one or more messages include multiple parameters, it means that the parameters among the multiple parameters are in at least one of the one or more messages, but not necessarily in each of the one or more messages.

[0043] Many of the features presented are described as optional by using "may" or by using parentheses. For the sake of brevity and readability, the present disclosure does not explicitly recite every permutation that can be obtained by choosing from the group of optional features. The present disclosure should be construed as explicitly disclosing all such permutations. For example, a system described as having three optional features can be embodied in seven different ways, namely having only one of the three possible features, having any two of the three possible features, or having all three of the three possible features.

[0044] Many of the elements described in the disclosed embodiments can be implemented as modules. A module is defined herein as an element that performs a defined function and has a defined interface to other elements. The modules described in the present disclosure can be implemented in hardware, software in combination with hardware, firmware, wetware (e.g., hardware with biological elements), or combinations thereof, all of which can be behaviorally equivalent. For example, a module can be implemented as a software routine written in a computer language configured to be executed by a hardware machine (such as C, C++, Fortran, Java, Basic, Matlab, etc.) or a modeling / simulation program (such as Simulink, Stateflow, GNU Octave, or LabVIEW MathScript). It is possible to implement a module using physical hardware incorporating discrete or programmable analog, digital, and / or quantum hardware. Examples of programmable hardware include: computers, microcontrollers, microprocessors, application-specific integrated circuits (ASICs); field-programmable gate arrays (FPGAs); and complex programmable logic devices (CPLDs). Computers, microcontrollers, and microprocessors are programmed using languages such as assembly, C, C++. FPGAs, ASICs, and CPLDs are often programmed using hardware description languages (HDLs), such as VHSIC hardware description language (VHDL) or Verilog, which configure the connections between the less functional internal hardware modules on the programmable device. The techniques mentioned are often used in combination to achieve the result of a functional module.

[0045] Figure 1A An example of a mobile communication network 100 in which embodiments of the present disclosure can be implemented is shown. The mobile communication network 100 can be, for example, a public land mobile network (PLMN) operated by a network operator. As Figure 1A shown, the mobile communication network 100 includes a core network (CN) 102, a radio access network (RAN) 104, and wireless devices 106.

[0046] CN 102 can provide an interface to one or more data networks (DNs), such as a public DN (e.g., the Internet), a private DN, and / or an intra-carrier DN, to the wireless device 106. As part of the interface function, CN 102 can establish an end-to-end connection between the wireless device 106 and one or more DNs, authenticate the wireless device 106, and provide a charging function.

[0047] RAN 104 can connect CN 102 to the wireless device 106 via radio communication over an air interface. As part of the radio communication, RAN 104 can provide scheduling, radio resource management, and retransmission protocols. The communication direction from RAN 104 to the wireless device 106 over the air interface is referred to as the downlink, while the communication direction from the wireless device 106 to RAN 104 over the air interface is referred to as the uplink. Frequency division duplexing (FDD), time division duplexing (TDD), and / or some combination of the two duplexing techniques can be used to separate downlink transmissions from uplink transmissions.

[0048] The term "wireless device" can be used throughout this disclosure to mean and encompass any mobile device or fixed (non-mobile) device that requires or can use wireless communication. For example, a wireless device can be a phone, smartphone, tablet, computer, laptop, sensor, meter, wearable device, Internet of Things (IoT) device, vehicle roadside unit (RSU), relay node, automobile, and / or any combination thereof. The term "wireless device" encompasses other terms, 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] RAN 104 can include one or more base stations (not shown). The term "base station" can be used throughout this disclosure to mean and encompass: Node B (associated with UMTS and / or 3G standards); evolved Node B (eNB, associated with E-UTRA and / or 4G standards); remote radio head (RRH); a baseband processing unit coupled to one or more RRHs; a repeater node or relay node for extending the coverage area of a donor node; next-generation evolved Node B (ng-eNB); generation Node B (gNB, associated with NR and / or 5G standards); access point (AP, associated with, for example, WiFi or any other suitable wireless communication standard); and / or any combination thereof. A base station can include at least one gNB central unit (gNB-CU) and at least one gNB distributed unit (gNB-DU).

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

[0051] In addition to three-sector sites, other implementations of the base station are possible. For example, one or more of the base stations in RAN 104 may be implemented as sectorized sites with more or fewer than three sectors. One or more of the base stations in RAN 104 may be implemented as access points, baseband processing units coupled to a number of remote radio heads (RRHs), and / or repeaters or relay nodes for extending the coverage area of a donor node. The baseband processing unit coupled to the RRH may be part of a centralized or cloud RAN architecture, where the baseband processing unit may be centralized in a pool of baseband processing units or virtualized. The repeater node may amplify and replay the radio signals received from the donor node. The relay node may perform the same / similar functions as the repeater node, but may decode the radio signals received from the donor node to remove noise before amplifying and replaying the radio signals.

[0052] RAN 104 may be deployed as a homogeneous network of macrocell base stations with similar antenna patterns and similar high-level transmission powers. RAN 104 may be deployed as a heterogeneous network. In a heterogeneous network, small cell base stations may be used to provide small coverage areas, such as coverage areas that overlap with the relatively large coverage areas provided by macrocell base stations. 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, in decreasing order of coverage area, include: microcell base stations, picocell base stations, and femtocell base stations or home base stations.

[0053] The 3rd Generation Partnership Project (3GPP) was established in 1998 to provide global specification standardization for mobile communication networks similar to Figure 1A mobile communication network 100 herein. So far, 3GPP has developed specifications for three generations of mobile networks: the 3rd generation (3G) network known as Universal Mobile Telecommunications System (UMTS), the 4th generation (4G) network known as Long Term Evolution (LTE), and the 5th generation (5G) network known as 5G System (5GS). Embodiments of the present disclosure are described with reference to the RAN of the 3GPP 5G network referred to as Next Generation RAN (NG-RAN). These embodiments may be applicable to the RAN of other mobile communication networks, such asFigure 1A the RANs in [0000216], the RANs of early 3G and 4G networks, and those of future networks yet to be specified (e.g., 3GPP 6G networks). The NG-RAN implements the 5G radio access technology known as New Radio (NR) and can be configured to implement 4G radio access technology or other radio access technologies, including non-3GPP radio access technologies.

[0054] Figure 1B Another exemplary mobile communication network 150 is shown in which embodiments of the present disclosure may be implemented. The mobile communication network 150 may be, for example, a PLMN operated by a network operator. As Figure 1B shown, the mobile communication network 150 includes a 5G core network (5G-CN) 152, an NG-RAN 154, and UEs 156A and 156B (collectively referred to as UEs 156). These components may be implemented and operated in the same or similar manner as the corresponding components described with respect to Figure 1A the description.

[0055] The 5G-CN 152 provides an interface to one or more DNs to the UEs 156, such as a public DN (e.g., the Internet), a private DN, and / or an operator-internal DN. As part of the interface function, the 5G-CN 152 may establish an end-to-end connection between the UEs 156 and the one or more DNs, authenticate the UEs 156, and provide a charging function. Compared with the CN of the 3GPP 4G network, the basis of the 5G-CN 152 may be a service-based architecture. This means that the architecture of the nodes constituting the 5G-CN 152 may be defined as network functions that provide services to other network functions via interfaces. 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 Figure 1B shown, the 5G-CN 152 includes an access and mobility management function (AMF) 158A and a user plane function (UPF) 158B. For ease of illustration, in Figure 1BThey are shown as a single component AMF / UPF 158. UPF 158B can act as a gateway between the NG-RAN 154 and the one or more DNs. Functions that UPF 158B can perform include, for example, packet routing and forwarding, packet inspection, and user plane policy rule enforcement, traffic usage reporting, support for uplink classification for routing 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. UPF 158B can act as an anchor point for mobility within / across radio access technologies (RATs), an external protocol (or packet) data unit (PDU) session point interconnected with the one or more DNs, and / or a pivot point for supporting multi-homed PDU sessions. The UE 156 can be configured to receive services via a PDU session, which is a logical connection between the UE and a DN.

[0057] Functions that AMF 158A can perform include, for example, non-access stratum (NAS) signaling termination, NAS signaling security, access stratum (AS) security control, CN inter-node signaling for mobility between 3GPP access networks, reachability of idle mode UEs (e.g., control and execution of paging retransmission), registration area management, in-system and inter-system mobility support, access authentication, access authorization including roaming rights verification, mobility management control (subscription and policy), network slice support, and / or session management function (SMF) selection. NAS can refer to functions operating between the CN and the UE, and AS can refer to functions operating between the UE and the RAN.

[0058] The 5G-CN 152 can include one or more additional network functions not shown for clarity in Figure 1B For example, the 5G-CN 152 can include one or more of the following: session management function (SMF), NR repository function (NRF), policy control function (PCF), network exposure function (NEF), unified data management (UDM), application function (AF), and / or authentication server function (AUSF).

[0059] The NG-RAN 154 can connect the 5G-CN 152 to the UE 156 via radio communication over the air interface. The NG-RAN 154 can include: one or more gNBs, shown as gNB 160A and gNB 160B (collectively gNB 160); and / or one or more ng-eNBs, shown as ng-eNB 162A and ng-eNB 162B (collectively ng-eNB 162). The gNB 160 and ng-eNB 162 can be more generally referred to as base stations. The gNB 160 and ng-eNB 162 can include one or more sets of antennas for communicating with the UE 156 over the air interface. For example, one or more of the gNBs in the gNB 160 and / or one or more of the ng-eNBs in the ng-eNB 162 can include three sets of antennas to control three cells (or sectors) respectively. The cells of the gNB 160 and ng-eNB 162 can together provide radio coverage over a wide geographical area to support UE mobility.

[0060] As Figure 1B shown, the gNB 160 and / or ng-eNB 162 can be connected to the 5G-CN 152 via the NG interface and to other base stations via the Xn interface. The NG and Xn interfaces can be established using direct physical connections and / or indirect connections via an underlying transport network such as an Internet Protocol (IP) transport network. The gNB 160 and / or ng-eNB 162 can be connected to the UE 156 via the Uu interface. For example, as Figure 1B shown, the gNB 160A can be connected to the UE156A via the Uu interface. The NG, Xn, and Uu interfaces are associated with a protocol stack. The protocol stack associated with the interfaces can be used by Figure 1B the network elements in to exchange data and signaling messages and can include two planes: a user plane and a control plane. The user plane can handle data of interest to the user. The control plane can handle signaling messages of interest to the network elements.

[0061] gNB 160 and / or ng-eNB 162 may be connected to one or more AMF / UPF functions of 5G-CN 152, such as AMF / UPF 158, via one or more NG interfaces. For example, gNB 160A may be connected to UPF 158B of AMF / UPF 158 via an NG user plane (NG-U) interface. The NG-U interface may provide delivery (e.g., non-guaranteed delivery) of user plane PDUs between gNB 160A and UPF 158B. gNB 160A may be connected to AMF158A via an NG control plane (NG-C) interface. The NG-C interface may provide, for example, NG interface management, UE context management, UE mobility management, transmission of NAS messages, paging, PDU session management, and configuration delivery and / or warning message transmission.

[0062] gNB 160 may provide NR user plane and control plane protocol termination to UE 156 via the Uu interface. For example, gNB 160A may provide NR user plane and control plane protocol termination to UE 156A via the Uu interface associated with the first protocol stack. ng-eNB 162 may provide evolved UMTS terrestrial radio access (E-UTRA) user plane and control plane protocol termination to UE 156 via the Uu interface, where E-UTRA refers to the 3GPP 4G radio access technology. For example, ng-eNB 162B may provide E-UTRA user plane and control plane protocol termination to UE 156B via the Uu interface associated with the second protocol stack.

[0063] 5G-CN 152 is described as being configured to handle NR and 4G radio access. Those of ordinary skill in the art will understand that NR may be connected to the 4G core network in a mode referred to as "non-standalone operation". In non-standalone operation, the 4G core network is used to provide (or at least support) control plane functions (e.g., initial access, mobility, and paging). Although Figure 1B only one AMF / UPF 158 is shown, a gNB or ng-eNB may be connected to multiple AMF / UPF nodes to provide redundancy and / or load sharing across the multiple AMF / UPF nodes.

[0064] As discussed, Figure 1B the interfaces between the network elements in

[0065] Figure 2A andFigure 2B Examples of the NR user plane and NR control plane protocol stacks for the Uu interface between the UE 210 and the gNB 220 are shown respectively. Figure 2A and Figure 2B The protocol stacks shown in Figure 1B can be the same as or similar to those for the Uu interface between the UE156A and the gNB 160A shown in

[0066] Figure 2A An NR user plane protocol stack including five layers implemented in the UE 210 and the gNB 220 is shown. At the bottom of the protocol stack, the physical layers (PHY) 211 and 221 can provide transport services to the higher layers of the protocol stack and can correspond to layer 1 of the Open Systems Interconnection (OSI) model. The next four protocols above the PHY 211 and 221 include the Medium Access Control layers (MAC) 212 and 222, the Radio Link Control layers (RLC) 213 and 223, the Packet Data Convergence Protocol layers (PDCP) 214 and 224, and the Service Data Application Protocol layers (SDAP) 215 and 225. These four protocols can together constitute layer 2 or the data link layer of the OSI model.

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

[0068] PDCP 214 and 224 can perform header compression / decompression to reduce the amount of data to be transmitted over the air interface, can perform encryption / decryption to prevent unauthorized decoding of data transmitted over the air interface, and can perform integrity protection to ensure that control messages originate from the expected source. PDCP 214 and 224 can perform retransmission of undelivered packets, in-order delivery and reordering of packets, and removal of packets received repeatedly due to, for example, handover within the gNB. PDCP 214 and 224 can perform packet duplication to increase the likelihood of a packet being received, and remove any duplicate packets at the receiver. Packet duplication can be applied to services that require high reliability.

[0069] Although Figure 3 not shown in, PDCP 214 and 224 can perform mapping / demapping between split radio bearers and RLC channels in a dual-connectivity scenario. Dual connectivity is a technique that allows a UE to be connected to two cells or more generally to two cell groups: a master cell group (MCG) and a secondary cell group (SCG). A split bearer is a split bearer when a single radio bearer (such as one of the radio bearers provided by PDCP 214 and 224 as a service to SDAP 215 and 225) is handled by cell groups in a dual-connectivity. PDCP 214 and 224 can map / demap split radio bearers between RLC channels belonging to cell groups.

[0070] RLC 213 and 223 can perform segmentation, retransmission via automatic repeat request (ARQ), and removal of duplicate data units received from MAC 212 and 222, respectively. RLC 213 and 223 can support three transmission modes: transparent mode (TM); unacknowledged mode (UM); and acknowledged mode (AM). Based on the transmission mode in which the RLC is operating, the RLC can perform one or more of the functions. RLC configuration can be per logical channel, independent of the parameter set and / or transmission time interval (TTI) duration. As Figure 3 shown in, RLC 213 and 223 can provide RLC channels as services to PDCP 214 and 224, respectively.

[0071] MACs 212 and 222 can perform multiplexing / demultiplexing of logical channels and / or mapping between logical channels and transport channels. Multiplexing / demultiplexing can include: multiplexing data units belonging to the one or more logical channels into transport blocks (TBs) delivered to / from PHYs 211 and 221 and demultiplexing the data units from the transport blocks. MAC 222 can be configured to perform scheduling, scheduling information reporting, and priority handling between UEs by means of dynamic scheduling. Scheduling can be performed at gNB 220 (at MAC 222) for both downlink and uplink. MACs 212 and 222 can be configured to perform error correction via hybrid automatic repeat request (HARQ) (e.g., one HARQ entity per carrier in the case of carrier aggregation (CA)), priority handling between logical channels of UE210 by means of logical channel prioritization, and / or padding. MACs 212 and 222 can support one or more parameter sets and / or transmission timings. In an example, the mapping restrictions in logical channel prioritization can control which parameter set and / or transmission timing a logical channel can use. As Figure 3 shown, MACs 212 and 222 can provide logical channels as services to RLCs 213 and 223.

[0072] PHYs 211 and 221 can perform mapping of transport channels to physical channels and digital and analog signal processing functions for transmitting and receiving information over the air interface. These digital and analog signal processing functions can include, for example, encoding / decoding and modulation / demodulation. PHYs 211 and 221 can perform multi-antenna mapping. As Figure 3 shown, PHYs 211 and 221 can provide one or more transport channels as services to MACs 212 and 222.

[0073] Figure 4A An exemplary downlink data flow through the NR user plane protocol stack is shown. Figure 4A Shows the downlink data flow of three IP packets ( n , n+1 and m ) flowing through the NR user plane protocol stack to generate two TBs at gNB 220. The uplink data flow through the NR user plane protocol stack can be similar to the Figure 4A depicted downlink data flow.

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

[0075] Figure 4A The remaining protocol layers in Figure 3 can perform their associated functions (e.g., regarding Figure 4A ), add the corresponding headers and forward their respective outputs to the next lower layer. For example, PDCP 224 can perform IP header compression and encryption and forward its output to RLC 223. RLC 223 can optionally perform segmentation (e.g., as m shown for the IP packet Figure 4A ) and forward its output to MAC 222. MAC 222 can multiplex a number of RLC PDUs and can attach a MAC sub-header to the RLC PDU to form a transport block. In NR, the MAC sub-header can be distributed throughout the MAC PDU, as

[0076] Figure 4B shown. In LTE, the MAC sub-header can be entirely located at the beginning of the MAC PDU. The NR MAC PDU structure can reduce the processing time and the associated latency because the MAC PDU sub-header can be calculated before the complete MAC PDU is assembled.

[0077] Figure 4B Further shows a MAC control element (CE) inserted into the MAC PDU by the MAC (such as MAC 223 or MAC 222). For example, Figure 4B shows two MAC CEs inserted into the MAC PDU. It can be at the beginning of the downlink transmission of the MAC PDU (as Figure 4Bas shown in

[0078] Before describing the NR control plane protocol stack, the mapping between logical channels, transport channels, and physical channels, and the channel types, is first described. One or more of these channels can be used to perform functions associated with the NR control plane protocol stack described later herein.

[0079] Figure 5A and Figure 5B The mapping between logical channels, transport channels, and physical channels is shown for the downlink and uplink, respectively. Information is transferred through channels between the RLC, MAC, and PHY of the NR protocol stack. Logical channels can be used between the RLC and the MAC and can be classified as control channels that carry control and configuration information in the NR control plane, or as traffic channels that carry data in the NR user plane. Logical channels can be classified as dedicated logical channels dedicated to a particular UE, or as common logical channels that can be used by more than one UE. Logical channels can also be defined by the type of information they carry. The set of logical channels defined by NR includes, for example:

[0080] - Paging control channel (PCCH), which is used to carry paging messages for paging UEs whose location is unknown to the network at the cell level;

[0081] - Broadcast control channel (BCCH), which is used to carry system information messages in the form of a master information block (MIB) and several system information blocks (SIB), where the system information messages can be used by the UE to obtain information on how the cell is configured and how to operate within the cell;

[0082] - Common control channel (CCCH), which is used to carry control messages and random access;

[0083] - Dedicated Control Channel (DCCH), which is used to carry control messages to a specific UE / carry control messages from a specific UE to configure the UE; and

[0084] - Dedicated Traffic Channel (DTCH), which is used to carry user data to a specific UE / carry user data from a specific UE.

[0085] Transport channels are used between the MAC layer and the PHY layer and can be defined by how the information they carry is transmitted over the air interface. The set of transport channels defined by NR includes, for example:

[0086] - Paging Channel (PCH), which is used to carry paging messages originating from the PCCH;

[0087] - Broadcast Channel (BCH), which is used to carry the MIB from the BCCH;

[0088] - Downlink Shared Channel (DL-SCH), which is used to carry downlink data and signaling messages, including the SIB from the BCCH;

[0089] - Uplink Shared Channel (UL-SCH), which is used to carry uplink data and signaling messages; and

[0090] - Random Access Channel (RACH), which is used to allow a UE to access the network without any prior scheduling.

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

[0092] - Physical Broadcast Channel (PBCH), which is used to carry the MIB from the BCH;

[0093] - Physical Downlink Shared Channel (PDSCH), which is used to carry downlink data and signaling messages from the DL-SCH and paging messages from the PCH;

[0094] - Physical Downlink Control Channel (PDCCH), which is used to carry downlink control information (DCI), which can include downlink scheduling commands, uplink scheduling grants, and uplink power control commands;

[0095] - Physical Uplink Shared Channel (PUSCH), which is used to carry uplink data and signaling messages from the UL-SCH and, in some cases, carry uplink control information (UCI) as described below;

[0096] - Physical Uplink Control Channel (PUCCH), which is used to carry UCI, which may include HARQ acknowledgments, Channel Quality Indicator (CQI), Precoding Matrix Indicator (PMI), Rank Indicator (RI), and Scheduling Request (SR); and

[0097] - Physical Random Access Channel (PRACH), which is used for random access.

[0098] Similar to physical control channels, the physical layer generates physical signals to support the low-level operations of the physical layer. As Figure 5A and Figure 5B shown, the physical layer signals defined by NR include: Primary Synchronization Signal (PSS), Secondary Synchronization Signal (SSS), Channel State Information Reference Signal (CSI-RS), Demodulation Reference Signal (DMRS), Sounding Reference Signal (SRS), and Phase Tracking Reference Signal (PT-RS). These physical layer signals will be described in more detail below.

[0099] Figure 2B illustrates an exemplary NR control plane protocol stack. As Figure 2B shown, the NR control plane protocol stack can use the same / similar first four protocol layers as the exemplary NR user plane protocol stack. These four protocol layers include PHY 211 and 221, MAC 212 and 222, RLC 213 and 223, and PDCP 214 and 224. Instead of having SDAP 215 and 225 at the top of the stack as in the NR user plane protocol stack, the NR control plane protocol stack has Radio Resource Control (RRC) 216 and 226 and NAS protocol 217 and 237 at the top of this NR control plane protocol stack.

[0100] NAS protocols 217 and 237 can provide control plane functions between UE 210 and AMF 230 (e.g., AMF 158A) or more generally between UE210 and the CN. NAS protocols 217 and 237 can provide control plane functions between UE 210 and AMF 230 via signaling messages called NAS messages. There is no direct path through which NAS messages can be transmitted between UE 210 and AMF 230. The AS of the Uu and NG interfaces can be used to transmit NAS messages. NAS protocols 217 and 237 can provide control plane functions such as authentication, security, connection setup, mobility management, and session management.

[0101] RRCs 216 and 226 can provide control plane functions between the UE 210 and the gNB 220 or, more generally, between the UE 210 and the RAN. RRCs 216 and 226 can provide control plane functions between the UE 210 and the gNB 220 via signaling messages called RRC messages. RRC messages can 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 can multiplex control plane and user plane data into the same transport block (TB). Control plane functions that RRCs 216 and 226 can provide include, for example: broadcasting of system information related to the AS and NAS; paging initiated by the CN or the RAN; establishment, maintenance, and release of the 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; UE measurement reporting and control of the report; detection of radio link failure (RLF) and recovery from radio link failure; and / or NAS message transfer. As part of establishing the RRC connection, RRCs 216 and 226 can establish an RRC context, which can involve configuring parameters for communication between the UE 210 and the RAN.

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

[0103] In the RRC connected 602, the UE has an established RRC context and can have at least one RRC connection with the base station. The base station can be similar to one of the following: Figure 1A one or more base stations included in the RAN 104 depicted in Figure 1B or one of the gNB 160 or ng-eNB 162 depicted in Figure 2A and Figure 2BgNB 220 depicted therein; or any other base station described in the present disclosure. The base station connected to the UE may have an RRC context for the UE. The RRC context, referred to as the UE context, may include parameters for communication between the UE and the base station. These parameters may include, for example: one or more AS contexts; one or more radio link configuration parameters; bearer configuration information (e.g., related to data radio bearers, signaling radio bearers, logical channels, QoS flows, and / or PDU sessions); security information; and / or PHY, MAC, RLC, PDCP, and / or SDAP layer configuration information. When in the RRC connected state 602, the mobility of the UE may be managed by the RAN (e.g., RAN 104 or NG-RAN 154). The UE may measure the signal levels (e.g., reference signal levels) from the serving cell and neighboring cells and report these measurements to the base station currently serving the UE. The serving base station of the UE 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 the RRC connected state 602 to the RRC idle state 604 through a connection release procedure 608, or to the RRC inactive state 606 through a connection deactivation procedure 610.

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

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

[0106] The RRC state can 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 events via paging messages without having to broadcast the paging messages across the entire mobile communication network. The mobility management mechanism used in RRC idle 604 and RRC inactive 606 can allow the network to track the UE at the cell group level such that the paging message can be broadcast on the cells within the cell group in which the UE is currently resident rather than across the entire mobile communication network. The mobility management mechanism for RRC idle 604 and RRC inactive 606 tracks the UE at the cell group level. These mobility management mechanisms can do so using different granularities of grouping. For example, there can be three levels of cell grouping granularity: individual cells; cells within a RAN area identified by a RAN area identifier (RAI); and cells within a group of RAN areas called a tracking area and identified by a tracking area identifier (TAI).

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

[0108] The RAN area can be used to track the UE at the RAN level. For a UE in the RRC inactive 606 state, a RAN notification area can be assigned to the UE. The RAN notification area can include one or more cell identifiers, a list of RAIs, or a list of TAIs. In an example, a base station can belong to one or more RAN notification areas. In an example, a cell can belong to one or more RAN notification areas. If the UE moves by cell reselection to a cell not included in the RAN notification area assigned to the UE, the UE can perform a notification area update to the RAN to update the UE's RAN notification area.

[0109] The base station that stores the RRC context for the UE or the UE's last serving base station can be referred to as an anchor base station. The anchor base station can maintain the RRC context for the UE at least for the period during which the UE remains within the RAN notification area of the anchor base station and / or for the period during which the UE remains in RRC inactive 606.

[0110] gNB, such as Figure 1BThe gNB 160 therein can be divided into two parts: a central unit (gNB-CU) and one or more distributed units (gNB-DU). The gNB-CU can be coupled to one or more gNB-DUs using the F1 interface. The gNB-CU can include RRC, PDCP, and SDAP. The gNB-DU can include RLC, MAC, and PHY.

[0111] In NR, physical signals and physical channels (with respect to Figure 5A and Figure 5B being discussed) can be mapped to orthogonal frequency division multiplexing (OFDM) symbols. OFDM is a multi-carrier communication scheme that transmits data through F orthogonal sub-carriers (or tones). Before transmission, the data can be mapped to a series of complex symbols called source symbols (e.g., M-orthogonal amplitude modulation (M-QAM) symbols or M-phase shift keying (M-PSK) symbols), and divided into F parallel symbol streams. The F parallel symbol streams can be considered as if 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 can take F source symbols (one source symbol from each of the F parallel symbol streams), and use each source symbol to modulate the amplitude and phase of one of the F sine basis functions corresponding to F orthogonal sub-carriers. The output of the IFFT block can be F time domain samples representing the sum of F orthogonal sub-carriers. The F time domain samples can form a single OFDM symbol. After some processing (e.g., addition of a cyclic prefix) and up-conversion, the OFDM symbol provided by the IFFT block can be transmitted over the air interface at the carrier frequency. The F parallel symbol streams can be mixed using an FFT block before being processed by the IFFT block. This operation produces a discrete Fourier transform (DFT) precoded OFDM symbol and can be used by the UE in the uplink to reduce the peak-to-average power ratio (PAPR). The inverse processing of the OFDM symbol can be performed at the receiver using the FFT block to recover the data mapped to the source symbols.

[0112] Figure 7An exemplary configuration of an NR frame into which OFDM symbols are grouped is shown. The NR frame can be identified by a system frame number (SFN). The SFN can repeat with a period of 1024 frames. As shown, the duration of one NR frame can be 10 milliseconds (ms), and it can include 10 subframes with a duration of 1 ms each. A subframe can be divided into time slots, which include, for example, 14 OFDM symbols per time slot.

[0113] The duration of a time slot can depend on the parameter set of the OFDM symbols used for that time slot. In NR, flexible parameter sets are supported to accommodate different cell deployments (e.g., cells with carrier frequencies below 1 GHz up to cells with carrier frequencies in the mmWave range). The parameter sets can be defined in terms of subcarrier spacing and cyclic prefix duration. For the parameter sets in NR, the subcarrier spacing can be scaled by a power of two from a baseline subcarrier spacing of 15 kHz, and the cyclic prefix duration can be scaled by a power of two from a baseline cyclic prefix duration of 4.7 μs. For example, NR defines parameter sets with the following subcarrier spacing / cyclic prefix duration combinations: 15 kHz / 4.7 μs; 30 kHz / 2.3 μs; 60 kHz / 1.2 μs; 120 kHz / 0.59 μs; and 240 kHz / 0.29 μs.

[0114] A time slot can have a fixed number of OFDM symbols (e.g., 14 OFDM symbols). Parameter sets with higher subcarrier spacing have shorter time slot durations and correspondingly more time slots per subframe. Figure 7 An exemplary transmission structure of time slot duration and time slots per subframe related to the parameter set is shown (for ease of illustration, Figure 7 the parameter set with a subcarrier spacing of 240 kHz is not shown). A subframe in NR can be used as a time reference independent of the parameter set, while a time slot can be used as a unit for scheduling uplink and downlink transmissions. To support low latency, scheduling in NR can be decoupled from the time slot duration and start at any OFDM symbol and continue for as many symbols as required for the transmission. These partial time slot transmissions can be referred to as micro time slots or sub time slot transmissions.

[0115] Figure 8 An exemplary configuration of a time slot in the time and frequency domains of an NR carrier is shown. The time 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 Figure 8 shown. An RB spans twelve consecutive REs in the frequency domain, as Figure 8As shown. The NR carrier can be limited to a width of 275 RBs or 275×12 = 3300 subcarriers. If this limitation is used, for subcarrier spacings of 15 kHz, 30 kHz, 60 kHz, and 120 kHz, the NR carrier can be limited to 50 MHz, 100 MHz, 200 MHz, and 400 MHz respectively, where the 400 MHz bandwidth can be set based on a bandwidth limit of 400 MHz per carrier.

[0116] Figure 8 A single parameter set used across the entire bandwidth of the NR carrier is shown. In other exemplary configurations, multiple parameter sets can be supported on the same carrier.

[0117] NR can 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, in terms of UE power consumption, receiving the full carrier bandwidth may be prohibitive. In an example, to reduce power consumption and / or for other purposes, the UE can adapt the size of the UE's receive bandwidth based on the traffic volume the UE plans to receive. This is referred to as bandwidth adaptation.

[0118] NR defines a bandwidth part (BWP) to support UEs that cannot receive the full carrier bandwidth and to support bandwidth adaptation. In an example, a BWP can be defined by a subset of consecutive RBs on a carrier. A UE can be configured (e.g., via the 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 in the configured BWPs for a serving cell can be active. The one or more BWPs can be referred to as the active BWPs of the serving cell. When a serving cell is configured with a secondary uplink carrier, the serving cell can 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 spectrum, if the downlink BWP index of the downlink BWP is the same as the uplink BWP index of the uplink BWP, the downlink BWP from the set of configured downlink BWPs can be linked to the uplink BWP from the set of configured uplink BWPs. For unpaired spectrum, the UE can expect the center frequency of the downlink BWP to be the same as the center frequency of the uplink BWP.

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

[0121] For an uplink BWP in the set of configured uplink BWPs, the BS may configure for the UE one or more resource sets for one or more PUCCH transmissions. The UE may receive downlink reception (e.g., PDCCH or PDSCH) in the downlink BWP according to a set of configured parameters for the downlink BWP (e.g., subcarrier spacing and cyclic prefix duration). The UE may transmit uplink transmissions (e.g., PUCCH or PUSCH) in the uplink BWP according to the set of configured parameters (e.g., subcarrier spacing and cyclic prefix length of the uplink BWP).

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

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

[0124] The base station may configure a BWP inactivity timer value for the UE for the PCell. The UE may start or restart the BWP inactivity timer at any appropriate time. For example, the UE may start or restart the BWP inactivity timer when: ( a ) when the UE detects DCI indicating an active downlink BWP other than the default downlink BWP for paired spectrum operation; or ( b)When the UE detects DCI for an active downlink BWP or an active uplink BWP for unpaired spectrum operation other than the default downlink BWP or uplink BWP. If the UE does not detect DCI within a time interval (e.g., 1 ms or 0.5 ms), the UE may run the BWP inactivity timer towards expiration (e.g., incrementing from zero to the BWP inactivity timer value, or decrementing 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, the base station may configure the UE semi-statically with one or more BWPs. The UE may switch the active BWP from the first BWP to the second BWP in response to receiving DCI indicating that the second BWP is the active BWP and / or in response to the expiration of the BWP inactivity timer (e.g., in the case where the second BWP is the default BWP).

[0126] Downlink and uplink BWP switches may be performed independently in paired spectrum (where a BWP switch refers to switching from the current active BWP to a non-current active BWP). In unpaired spectrum, downlink and uplink BWP switches may be performed simultaneously. A switch may occur between the configured BWPs based on RRC signaling, DCI, expiration of the BWP inactivity timer, and / or initiation of random access.

[0127] Figure 9 An example of bandwidth adaptation using three configured BWPs with an NR carrier is shown. A UE configured with the three BWPs may switch from one BWP to another at a handover point. In Figure 9 the example shown, the BWPs include: BWP 902, which has a bandwidth of 40 MHz and a subcarrier spacing of 15 kHz; BWP 904, which has a bandwidth of 10 MHz and a subcarrier spacing of 15 kHz; and BWP 906, which has a bandwidth of 20 MHz and a subcarrier spacing of 60 kHz. BWP 902 may be the initial active BWP, and BWP 904 may be the default BWP. The UE may switch between the BWPs at the handover point. In Figure 9In the example, the UE may switch from BWP 902 to BWP 904 at handover point 908. The handover at handover point 908 may occur for any suitable reason, such as in response to the expiration of the BWP inactivity timer (indicating a handover to the default BWP) and / or in response to receiving DCI indicating that BWP 904 is the active BWP. The UE may switch from the active BWP 904 to BWP 906 at handover point 910 in response to receiving DCI indicating that BWP 906 is the active BWP. The UE may switch from the active BWP 906 to BWP 904 at handover point 912 in response to the expiration of the BWP inactivity timer and / or in response to receiving DCI indicating that BWP 904 is the active BWP. The UE may switch from the active BWP 904 to BWP 902 at handover point 914 in response to receiving DCI indicating that BWP 902 is the active BWP.

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

[0129] To provide higher data rates, carrier aggregation (CA) may be used to aggregate two or more carriers and transmit simultaneously to / from the same UE. The aggregated carriers in CA may be referred to as component carriers (CCs). When using CA, there are multiple serving cells for the UE, one serving cell per CC. The CCs may have three configurations in the frequency domain.

[0130] Figure 10A Three CA configurations with two CCs are shown. In the in-band contiguous configuration 1002, the two CCs are aggregated in the same frequency band (band A) and are positioned directly adjacent to each other within the band. In the in-band non-contiguous configuration 1004, the two CCs are aggregated in the same frequency band (band A) and are separated by a certain gap within the band. In the inter-band configuration 1006, the two CCs are in different bands (band A and band B).

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

[0132] When using CA, one of the aggregated cells in the aggregated cells for the UE can be referred to as the primary cell (PCell). The PCell can be the serving cell to which the UE is initially connected at RRC connection establishment, re - establishment, and / or handover. The PCell can provide the UE with NAS mobility information and security inputs. The UE can have different PCells. In the downlink, the carrier corresponding to the PCell can be referred to as the downlink primary CC (DL PCC). In the uplink, the carrier corresponding to the PCell can be referred to as the uplink primary CC (UL PCC). The other aggregated cells for the UE can be referred to as secondary cells (SCells). In an example, the SCell can be configured after the PCell is configured for the UE. For example, the SCell can be configured through the RRC connection re - configuration procedure. In the downlink, the carrier corresponding to the SCell can be referred to as the downlink secondary CC (DL SCC). In the uplink, the carrier corresponding to the SCell can be referred to as the uplink secondary CC (UL SCC).

[0133] The configured SCell for the UE can be activated and deactivated based on, for example, traffic and channel conditions. Deactivation of the SCell can mean stopping PDCCH and PDSCH reception on the SCell, and stopping PUSCH, SRS, and CQI transmission on the SCell. MAC CE regarding Figure 4B can be used to activate and deactivate the configured SCell. For example, the MAC CE can use a bitmap (e.g., one bit per SCell) to indicate which SCells (e.g., in a subset of the configured SCells) for the UE are activated or deactivated. The configured SCell can be deactivated in response to the expiration of an SCell deactivation timer (e.g., one SCell deactivation timer per SCell).

[0134] Downlink control information of a cell (such as scheduling assignment and scheduling grant) can be transmitted on the cell corresponding to the assignment and grant, which is called self-scheduling. The DCI of a cell can be transmitted on another cell, which is called cross-carrier scheduling. The uplink control information for aggregated cells (e.g., HARQ acknowledgments and channel state feedback such as CQI, PMI, and / or RI) can be transmitted on the PUCCH of the PCell. For a large number of aggregated downlink CCs, the PUCCH of the PCell may become overloaded. A cell can be divided into multiple PUCCH groups.

[0135] Figure 10B An example of how aggregated cells can be configured into one or more PUCCH groups is shown. PUCCH group 1010 and PUCCH group 1050 can each include one or more downlink CCs. In Figure 10B the example, PUCCH group 1010 includes three downlink CCs: PCell 1011, SCell 1012, and SCell 1013. PUCCH group 1050 includes three downlink CCs in this example: PCell 1051, SCell 1052, and SCell 1053. One or more uplink CCs can be configured as PCell 1021, SCell 1022, and SCell 1023. One or more other uplink CCs can be configured as the primary SCell (PSCell) 1061, SCell 1062, and SCell 1063. The uplink control information (UCI) related to the downlink CCs of PUCCH group 1010 (shown as UCI 1031, UCI 1032, and UCI 1033) can be transmitted in the uplink of PCell1021. The uplink control information (UCI) related to the downlink CCs of PUCCH group 1050 (shown as UCI 1071, UCI 1072, and UCI 1073) can be transmitted in the uplink of PSCell 1061. In the example, if Figure 10B the aggregated cells depicted in

[0136] A physical cell ID and a cell index can be assigned to a cell including a downlink carrier and an optional uplink carrier. The physical cell ID or the cell index can identify the downlink carrier and / or the uplink carrier of the cell, e.g., depending on the context in which the physical cell ID is used. The physical cell ID can be determined using the synchronization signal transmitted on the downlink component carrier. The cell index can be determined using an RRC message. In the present disclosure, the physical cell ID can be referred to as a carrier ID, and the cell index can be referred to as a carrier index. For example, when the present disclosure relates to the first physical cell ID of the first downlink carrier, the present disclosure can mean that the first physical cell ID is for the cell including the first downlink carrier. The same / similar concept can apply to, e.g., carrier activation. When the present disclosure indicates that the first carrier is activated, this specification can mean that the cell including the first carrier is activated.

[0137] In CA, the multi-carrier nature of the PHY can be exposed to the MAC. In an example, the HARQ entity can operate on the serving cell. The transport block can be generated according to the assignment / grant of each serving cell. The transport block and the potential HARQ retransmission of the transport block can be mapped to the serving cell.

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

[0139] Figure 11A An example of the structure and location of the SS / PBCH block is shown. The burst of SS / PBCH blocks can include one or more SS / PBCH blocks (e.g., 4 SS / PBCH blocks, as Figure 11A shown). The burst can be transmitted periodically (e.g., every 2 frames or 20 ms). The burst can be limited to a half-frame (e.g., the first half-frame with a duration of 5 ms). It should be understood that Figure 11Aare examples, and these parameters (the number of SS / PBCH blocks per burst, the period of the burst, the position of the burst within the frame) can be configured based on, for example, the following: the carrier frequency of the cell in which the SS / PBCH blocks are transmitted; the parameter set or subcarrier spacing of the cell; the configuration by the network (e.g., using RRC signaling); or any other suitable factor. In an example, the UE can assume the subcarrier spacing of the SS / PBCH blocks based on the carrier frequency being monitored, unless the radio network configures the UE to assume a different subcarrier spacing.

[0140] The SS / PBCH blocks can span one or more OFDM symbols in the time domain (e.g., 4 OFDM symbols, as shown in the example of Figure 11A ), and can span one or more subcarriers in the frequency domain (e.g., 240 consecutive subcarriers). The PSS, SSS, and PBCH can have a common center frequency. The PSS can be transmitted first and can span, for example, 1 OFDM symbol and 127 subcarriers. The SSS can be transmitted after the PSS (e.g., after two symbols) and can span 1 OFDM symbol and 127 subcarriers. The PBCH can be transmitted after the PSS (e.g., spanning the next 3 OFDM symbols) and can span 240 subcarriers.

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

[0142] The SS / PBCH blocks can be used by the UE to determine one or more parameters of the cell. For example, the UE can determine the physical cell identifier (PCI) of the cell based on the sequences of the PSS and SSS respectively. The UE can determine the position of the frame boundary of the cell based on the position of the SS / PBCH blocks. For example, the SS / PBCH blocks can indicate that they have been transmitted according to a transmission pattern, where the SS / PBCH blocks in that transmission pattern are a known distance from the frame boundary.

[0143] The PBCH can use QPSK modulation and can use forward error correction (FEC). The FEC can use polar coding. One or more symbols spanned by the PBCH can carry one or more DMRSs for demodulating the PBCH. The PBCH can include an indication of the current system frame number (SFN) of the cell and / or the SS / PBCH block timing index. These parameters can assist the UE in time synchronization with the base station. The PBCH can include a master information block (MIB) for providing one or more parameters to the UE. The MIB can be used by the UE to locate the remaining minimum system information (RMSI) associated with the cell. The RMSI can include system information block type 1 (SIB1). The SIB1 can contain the information required for the UE to access the cell. The UE can use one or more parameters of the MIB to monitor the PDCCH that can be used to schedule the PDSCH. The PDSCH can include the SIB1. The parameters provided in the MIB can be used to decode the SIB1. The PBCH can indicate the non-existence of the SIB1. Based on the PBCH indicating the non-existence of the SIB1, the UE can point to a frequency. The UE can search for the SS / PBCH block at the frequency pointed to by the UE.

[0144] The UE can assume that one or more SS / PBCH blocks transmitted with the same SS / PBCH block index are quasi-co-located (QCLed) (e.g., having the same / similar Doppler spread, Doppler shift, average gain, average delay, and / or spatial Rx parameters). The UE can not assume QCL for SS / PBCH block transmissions with different SS / PBCH block indexes.

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

[0146] In an example, within the frequency range of a carrier, the base station can transmit multiple SS / PBCH blocks. In an example, the first physical cell identifier (PCI) of the first SS / PBCH block of the multiple SS / PBCH blocks can be different from the second PCI of the second SS / PBCH block of the multiple SS / PBCH blocks. The PCIs of SS / PBCH blocks transmitted at different frequency positions can be different or the same.

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

[0148] The base station can semi-statically configure the UE using one or more CSI-RS resource sets. The CSI-RS resources can be associated with positions in the time domain and frequency domain as well as periodicity. The base station can selectively activate and / or deactivate the CSI-RS resources. The base station can indicate to the UE which CSI-RS resources in the CSI-RS resource set are activated and / or deactivated.

[0149] The base station can configure the UE to report CSI measurement values. The base station can configure the UE to provide CSI reports periodically, aperiodically, or semi-persistently. For periodic CSI reports, the UE can be configured with the timing and / or period of multiple CSI reports. For aperiodic CSI reports, the base station can request a CSI report. For example, the base station can command the UE to measure the configured CSI-RS resources and provide a CSI report related to the measurement values. For semi-persistent CSI reports, the base station can configure the UE to transmit periodically and selectively activate or deactivate the periodic report. The base station can configure the UE using CSI-RS resource sets and CSI reports using RRC signaling.

[0150] The CSI-RS configuration can include one or more parameters indicating, for example, up to 32 antenna ports. The UE can be configured to use the same OFDM symbol for the downlink CSI-RS and the control resource set (CORESET) when the downlink CSI-RS and the CORESET are spatially QCLed and the resource elements associated with the downlink CSI-RS are outside the physical resource blocks (PRBs) configured for the CORESET. The UE can be configured to use the same OFDM symbol for the downlink CSI-RS and the SS / PBCH block when the downlink CSI-RS and the SS / PBCH block are spatially QCLed and the resource elements associated with the downlink CSI-RS are outside the PRBs configured for the SS / PBCH block.

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

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

[0153] The PDSCH can include one or more layers. The UE can assume that at least one symbol with DMRS exists on a layer among the one or more layers of the PDSCH. The higher layer can configure up to 3 DMRSs for the PDSCH.

[0154] The downlink PT-RS can be transmitted by the base station and used by the UE for phase noise compensation. Whether the downlink PT-RS exists can depend on the RRC configuration. The presence and / or pattern of the downlink PT-RS can be configured on a UE-specific basis using a combination of RRC signaling and / or an association with one or more parameters that can be indicated by DCI for other purposes (e.g., modulation and coding scheme (MCS)). When configured, the dynamic presence of the downlink PT-RS can be associated with one or more DCI parameters including at least the MCS. The NR network can support multiple PT-RS densities defined in the time / frequency domain. When present, the frequency domain density can be associated with at least one configuration of the scheduled bandwidth. The UE can employ the same precoding for the DMRS port and the PT-RS port. The number of PT-RS ports can be less than the number of DMRS ports in the scheduled resources. The downlink PT-RS can be restricted to the scheduled time / frequency duration of the UE. The downlink PT-RS can be transmitted on symbols to assist in phase tracking at the receiver.

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

[0156] The PUSCH can include one or more layers, and the UE can transmit at least one symbol with DMRS on the layer(s) present in one or more layers of the PUSCH. In an example, the higher layer can configure up to three DMRS for the PUSCH.

[0157] Depending on the RRC configuration of the UE, uplink PT-RS (which can be used by the base station for phase tracking and / or phase noise compensation) may or may not be present. The presence and / or pattern of the uplink PT-RS can be configured on a UE-specific basis by a combination of RRC signaling and / or one or more parameters for other purposes (e.g., modulation and coding scheme (MCS)) that can be indicated by DCI. When configured, the dynamic presence of the uplink PT-RS can be associated with one or more DCI parameters including at least MCS. The radio network may support multiple uplink PT-RS densities defined in the time / frequency domain. When present, the frequency-domain density can be associated with at least one configuration of the scheduled bandwidth. The UE may employ the same precoding for DMRS ports and PT-RS ports. The number of PT-RS ports may be less than the number of DMRS ports in the scheduled resources. For example, the uplink PT-RS may be restricted to the scheduled time / frequency duration of the UE.

[0158] The UE may transmit SRS to the base station for channel state estimation to support uplink channel-dependent scheduling and / or link adaptation. The SRS transmitted by the UE may allow the base station to estimate the uplink channel state at one or more frequencies. The scheduler at the base station may use the estimated uplink channel state to assign one or more resource blocks for uplink PUSCH transmission from the UE. The base station may configure the UE semi-statically 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. The SRS resource set applicability may be configured by a higher layer (e.g., RRC) parameter. For example, when the higher layer parameter indicates beam management, the SRS resources in the one or more SRS resource sets (e.g., having the same / similar time-domain behavior, periodic, aperiodic, etc.) may be transmitted at a certain moment (e.g., simultaneously). The UE may transmit one or more SRS resources in the SRS resource set. The NR network may support aperiodic, periodic, and / or semi-persistent SRS transmission. The UE may transmit SRS resources based on one or more trigger types, where the one or more trigger types may include 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 configured SRS resource set from one or more configured SRS resource sets. SRS trigger type 0 may refer to SRS triggered based on higher layer signaling. SRS trigger type 1 may refer to SRS triggered based on one or more DCI formats. In an example, when PUSCH and SRS are transmitted in the same time slot, the UE may be configured to transmit SRS after the transmission of PUSCH and the corresponding uplink DMRS.

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

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

[0161] Channels using beamforming require beam management. Beam management may include beam measurement, beam selection, and beam indication. A beam may be associated with one or more 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 a downlink reference signal (e.g., channel state information reference signal (CSI-RS)) and generate a beam measurement report. After the RRC connection is set up by the base station, the UE may perform a downlink beam measurement procedure.

[0162] Figure 11B An example of a channel state information reference signal (CSI-RS) mapped in the time and frequency domains is shown. Figure 11BThe square shown in [description] can represent resource blocks (RBs) within the bandwidth of a cell. The base station may transmit one or more RRC messages including CSI-RS resource configuration parameters indicating one or more CSI-RSs. One or more of the following parameters may be configured for the CSI-RS resource configuration by higher layer signaling (e.g., RRC and / or MAC signaling): CSI-RS resource configuration identity, number of CSI-RS ports, CSI-RS configuration (e.g., symbols and resource element (RE) positions in a subframe), CSI-RS subframe configuration (e.g., subframe position, offset, and periodicity in a radio frame), CSI-RS power parameter, CSI-RS sequence parameter, code division multiplexing (CDM) type parameter, frequency density, transmission comb, quasi-co-location (QCL) parameter (e.g., QCL-scrambling identity, crs-portscount, mbsfn-subframeconfiglist, csi-rs-configZPid, qcl-csi-rs-configNZPid) and / or other radio resource parameters.

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

[0164] CSI-RS, such as Figure 11BThose shown in, for example, CSI-RS 1101, 1102, 1103 can be transmitted by the base station and used by the UE for one or more measurements. For example, the UE can measure the reference signal received power (RSRP) of the configured CSI-RS resources. The base station can configure the UE using a reporting configuration, and the UE can report the RSRP measurement to the network (e.g., via one or more base stations) based on the reporting configuration. In an example, the base station can determine one or more transmission configuration indication (TCI) states including multiple reference signals based on the reported measurement results. In an example, the base station can indicate one or more TCI states to the UE (e.g., via RRC signaling, MAC CE, and / or DCI). The UE can receive 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 beam correspondence capabilities. If the UE has beam correspondence capabilities, the UE can determine the spatial domain filter of the transmission (Tx) beam based on the spatial domain filter of the corresponding Rx beam. If the UE does not have beam correspondence capabilities, the UE can perform an uplink beam selection procedure to determine the spatial domain filter of the Tx beam. The UE can perform the uplink beam selection procedure based on one or more sounding reference signal (SRS) resources configured by the base station for the UE. The base station can select and indicate the uplink beam of the UE based on the measurement of one or more SRS resources transmitted by the UE.

[0165] In a beam management procedure, the UE can assess (e.g., measure) one or more beam pair links, including the beam pair links of the transmission beam transmitted by the base station and the channel quality of the receive beam received by the UE. Based on this assessment, the UE can transmit a beam measurement report indicating one or more beam pair quality parameters, the one or more beam pair quality parameters including, for example, one or more beam identifiers (e.g., beam index, reference signal index, etc.), RSRP, precoding matrix indicator (PMI), channel quality indicator (CQI), and / or rank indicator (RI).

[0166] Figure 12AIllustrates examples of three downlink beam management procedures: P1, P2, and P3. Procedure P1 can enable UE measurements of the transmission (Tx) beam of a transmission reception point (TRP) (or multiple TRPs), for example, to support the selection of one or more base station Tx beams and / or UE Rx beams (shown as ellipses in the top and bottom rows of P1, respectively). Beamforming at the TRP can include Tx beam sweeping for a set of beams (shown as an ellipse rotating in the counterclockwise direction indicated by the dashed arrow in the top rows of P1 and P2). Beamforming at the UE can include Rx beam sweeping for a set of beams (shown as an ellipse rotating in the clockwise direction indicated by the dashed arrow in the bottom rows of P1 and P3). Procedure P2 can be used to enable UE measurements of the Tx beam of the TRP (shown as an ellipse rotating in the counterclockwise direction indicated by the dashed arrow in the top row of P2). The UE and / or the base station can perform Procedure P2 using a smaller set of beams or beams that are narrower than the set of beams used in Procedure P1. This can be referred to as beam refinement. The UE can perform Procedure P3 for Rx beam determination by using the same Tx beam at the base station and sweeping the Rx beam at the UE.

[0167] Figure 12B Illustrates examples of three uplink beam management procedures: U1, U2, and U3. Procedure U1 can be used to enable the base station to perform measurements on the Tx beam of the UE, for example, to support the selection of one or more UE Tx beams and / or base station Rx beams (shown as ellipses in the top and bottom rows of U1, respectively). Beamforming at the UE can include, for example, Rx beam sweeping from a set of beams (shown as an ellipse rotating in the clockwise direction indicated by the dashed arrow in the bottom rows of U1 and U3). Beamforming at the base station can include, for example, Rx beam sweeping from a set of beams (shown as an ellipse rotating in the counterclockwise direction indicated by the dashed arrow in the top rows of U1 and U2). When the UE uses a fixed Tx beam, Procedure U2 can be used to enable the base station to adjust its Rx beam. The UE and / or the base station can perform Procedure U2 using a smaller set of beams or beams that are narrower than the set of beams used in Procedure P1. This can be referred to as beam refinement. The UE can perform Procedure U3 to adjust its Tx beam when the base station uses a fixed Rx beam.

[0168] The 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, UCI, SR, MAC CE, etc.) based on the initiation of the BFR procedure. The UE may detect a beam failure based on a determination that the quality of the beam pair link of the associated control channel is not satisfactory (e.g., having an error rate higher than an error rate threshold, a received signal power lower than a received signal power threshold, expiration of a timer, etc.).

[0169] The UE may measure the quality of the beam pair link using one or more reference signals (RSs), the one or more reference signals including one or more SS / PBCH blocks, one or more CSI-RS resources, and / or one or more demodulation reference signals (DMRSs). The quality of the beam pair link may be based on one or more of the following: block error rate (BLER), RSRP value, signal-to-interference-plus-noise ratio (SINR) value, reference signal received quality (RSRQ) value, and / or CSI value measured on the RS resource. The base station may indicate that the 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, etc.). The one or more DMRSs of the RS resource and the channel may be QCLed when the channel characteristics (e.g., Doppler shift, Doppler spread, average delay, delay spread, spatial Rx parameters, fading, etc.) of the transmission from the RS resource to the UE are similar or the same as the channel characteristics of the transmission from the channel to the UE.

[0170] The network (e.g., gNB and / or the ng-eNB of the network) and / or the UE may initiate a random access procedure. A UE in the RRC_IDLE state and / or the RRC_INACTIVE state may initiate a random access procedure to request connection setup to the network. The UE may initiate a random access procedure from the RRC_CONNECTED state. The UE may initiate a random access procedure to request uplink resources (e.g., uplink transmission for SR when no PUCCH resources are available) and / or obtain uplink timing (e.g., when the uplink synchronization state is not synchronized). The UE may initiate a random access procedure to request one or more system information blocks (SIBs) (e.g., other system information such as SIB2, SIB3, etc.). The UE may initiate a random access procedure for a beam failure recovery request. The network may initiate a random access procedure for handover and / or for establishing time alignment for SCell addition.

[0171] Figure 13A A four-step contention-based random access procedure is shown. Before initiating the procedure, the base station may transmit a configuration message 1310 to the UE. Figure 13AThe program shown includes the transmission of four messages: Msg 1 1311, Msg 2 1312, Msg3 1313, and Msg 4 1314. Msg 1 1311 may include and / or be referred to as a preamble (or random access preamble). Msg2 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 to the UE one or more random access channel (RACH) parameters. The one or more RACH parameters may include at least one of the following: general parameters for one or more random access procedures (e.g., RACH-configGeneral); cell-specific parameters (e.g., RACH-ConfigCommon); and / or dedicated parameters (e.g., RACH-configDedicated). The base station may broadcast or multicast the one or more RRC messages to one or more UEs. The one or more RRC messages may be UE-specific (e.g., dedicated RRC messages transmitted to the UE in the RRC_CONNECTED state and / or the RRC_INACTIVE state). The UE may determine the time-frequency resources and / or uplink transmission power for transmitting Msg 1 1311 and / or Msg 3 1313 based on the one or more RACH parameters. Based on the one or more RACH parameters, the UE may determine the reception timing and downlink channel for receiving Msg 2 1312 and Msg 4 1314.

[0173] The one or more RACH parameters provided in the configuration message 1310 may indicate one or more physical RACH (PRACH) opportunities available for transmitting Msg 11311. The one or more PRACH opportunities may be predefined. The one or more RACH parameters may indicate one or more available sets of one or more PRACH opportunities (e.g., prach-ConfigIndex). The one or more RACH parameters may indicate the association between (a) one or more PRACH opportunities and (b) one or more reference signals. The one or more RACH parameters may indicate the association between (a) one or more preambles and (b) one or more reference signals. The one or more reference signals may be SS / PBCH blocks and / or CSI-RS. For example, the one or more RACH parameters may indicate the number of SS / PBCH blocks mapped to a PRACH opportunity and / or the number of preambles mapped to an SS / PBCH block.

[0174] The one or more RACH parameters provided in the configuration message 1310 can be used to determine the uplink transmission power of Msg 1 1311 and / or Msg 3 1313. For example, the one or more RACH parameters can indicate a reference power for preamble transmission (e.g., the received target power and / or the initial power of preamble transmission). There can be one or more power offsets indicated by the one or more RACH parameters. For example, the one or more RACH parameters can indicate: the power ramp step; the power offset between the SSB and the CSI-RS; the power offset between the transmissions of Msg 1 1311 and Msg 3 1313; and / or the power offset value between preamble groups. The one or more RACH parameters can indicate one or more thresholds, based on which the UE can determine at least one reference signal (e.g., SSB and / or CSI-RS) and / or an uplink carrier (e.g., a normal uplink (NUL) carrier and / or a supplementary uplink (SUL) carrier).

[0175] Msg 1 1311 can include one or more preamble transmissions (e.g., preamble transmission and one or more preamble retransmissions). The RRC message can be used to configure one or more preamble groups (e.g., group A and / or group B). A preamble group can include one or more preambles. The UE can determine the preamble group based on the path loss measurement value and / or the size of Msg 3 1313. The UE can measure the RSRP of one or more reference signals (e.g., SSB and / or CSI-RS) and determine at least one reference signal having an RSRP higher than the RSRP threshold (e.g., rsrp-ThresholdSSB and / or rsrp-ThresholdCSI-RS). For example, if the association between the one or more preambles and the at least one reference signal is configured by the RRC message, the UE can select at least one preamble associated with the one or more reference signals and / or the selected preamble group.

[0176] The UE can determine the preamble based on the one or more RACH parameters provided in the configuration message 1310. For example, the UE can determine the preamble based on path loss measurement, RSRP measurement, and / or the size of Msg 3 1313. As another example, the one or more RACH parameters can indicate: preamble format; the maximum number of preamble transmissions; and / or one or more thresholds for determining one or more preamble groups (e.g., group A and group B). The base station can use the one or more RACH parameters to configure the association between one or more preambles and one or more reference signals (e.g., SSB and / or CSI-RS) for the UE. If this association is configured, the UE can determine the preamble included in Msg 1 1311 based on this association. Msg 1 1311 can be transmitted to the base station via one or more PRACH opportunities. The UE can use one or more reference signals (e.g., SSB and / or CSI-RS) to select the preamble and to determine the PRACH opportunity. One or more RACH parameters (e.g., ra-ssb-OccasionMskIndex and / or ra-OccasionList) can indicate the association between the PRACH opportunity and the one or more reference signals.

[0177] If no response is received after the preamble transmission, the UE can perform a preamble retransmission. The UE can increase the uplink transmission power for the preamble retransmission. The UE can select the initial preamble transmission power based on the path loss measurement value and / or the target received preamble power configured by the network. The UE can determine the retransmission preamble and can ramp up the uplink transmission power. The UE can receive one or more RACH parameters (e.g., PREAMBLE_POWER_RAMPING_STEP) indicating the ramp-up step size for the preamble retransmission. The ramp-up step size can be the amount of incremental increase in the uplink transmission power for the retransmission. If the UE determines the same reference signal (e.g., SSB and / or CSI-RS) as the previous preamble transmission, the UE can ramp up the uplink transmission power. The UE can count the number of preamble transmissions and / or retransmissions (e.g., PREAMBLE_TRANSMISSION_COUNTER). For example, if the number of preamble transmissions exceeds the threshold (e.g., preambleTransMax) configured by the one or more RACH parameters, the UE can determine that the random access procedure has not been successfully completed.

[0178] Msg 2 1312 received by the UE may include an RAR. In some scenarios, Msg 2 1312 may include multiple RARs corresponding to multiple UEs. Msg 2 1312 may be received after or in response to the transmission of Msg 1 1311. Msg2 1312 may be scheduled on the DL-SCH and indicated on the PDCCH using a random access RNTI (RA-RNTI). Msg 2 1312 may indicate that Msg 1 1311 has been received by the base station. Msg 2 1312 may include a timing alignment command that can be used by the UE to adjust the UE's transmission timing, a scheduling grant for transmitting Msg 3 1313, and / or a temporary cell RNTI (TC-RNTI). After transmitting the preamble, the UE may start a time window (e.g., ra-ResponseWindow) to monitor the PDCCH of Msg 2 1312. The UE may determine when to start the time window based on the PRACH occasion used by the UE to transmit the preamble. For example, the UE may start a time window of one or more symbols after the last symbol of the preamble (e.g., at the first PDCCH occasion starting from the end of the preamble transmission). The one or more symbols may be determined based on the parameter set. The PDCCH may be in a common search space configured by an RRC message (e.g., Type1-PDCCH common search space). The UE may identify the RAR based on a radio network temporary identifier (RNTI). The RNTI may be used depending on one or more events that initiate the random access procedure. The UE may use a random access RNTI (RA-RNTI). The RA-RNTI may be associated with the PRACH occasion in which the UE transmits the preamble. For example, the UE may determine the RA-RNTI based on the following: OFDM symbol index; slot index; frequency domain index; and / or UL carrier indicator of the PRACH occasion. An example of the RA-RNTI may be as follows:

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

[0180] The UE may transmit Msg 3 1313 in response to successfully receiving Msg 2 1312 (e.g., using the resources identified in Msg 2 1312). Msg 3 1313 may be used for contention resolution in, for example Figure 13A the contention-based random access procedure shown in. In some scenarios, multiple UEs may transmit the same preamble to the base station, and the base station may provide a RAR corresponding to the UE. If the multiple UEs decode the RAR as corresponding to themselves, a conflict may occur. Contention resolution (e.g., using Msg 3 1313 and Msg 4 1314) may be used to increase the likelihood that a UE does not incorrectly use the identity of another UE. To perform contention resolution, the UE may include a device identifier in Msg 3 1313 (e.g., the TC-RNTI included in Msg 2 1312 and / or any other suitable identifier if a C-RNTI is assigned).

[0181] Msg 4 1314 may be received after or in response to the transmission of Msg 3 1313. If a C-RNTI is included in Msg 31313, the base station will address the UE on the PDCCH using the C-RNTI. If the unique C-RNTI of the UE is detected on the PDCCH, it is determined that the random access procedure has been successfully completed. If a TC-RNTI is included in Msg 3 1313 (e.g., if the UE is in the RRC_IDLE state or not otherwise connected to the base station), Msg 4 1314 will be received using the DL-SCH associated with the TC-RNTI. If the MAC PDU is successfully decoded and the MAC PDU includes a UE contention resolution identity MAC CE that matches or otherwise corresponds to the CCCH SDU sent (e.g., transmitted) in Msg 3 1313, the UE may determine that contention resolution is successful and / or the UE may determine that the random access procedure has been successfully completed.

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

[0183] Figure 13B A two-step contention-free random access procedure is shown. Similar to Figure 13A the four-step contention-based random access procedure shown, the base station can transmit a configuration message 1320 to the UE before the procedure is initiated. The configuration message 1320 can be similar to the configuration message 1310 in some aspects. Figure 13B The procedure shown includes the transmission of two messages: Msg 1 1321 and Msg 2 1322. Msg 1 1321 and Msg 2 1322 can be similar to Figure 13A the Msg 1 1311 and Msg 2 1312 shown respectively. As can be understood from Figure 13A and Figure 13B the contention-free random access procedure may not include messages similar to Msg 3 1313 and / or Msg 4 1314.

[0184] The contention-free random access procedure shown can be initiated for beam failure recovery, other SI requests, SCell addition, and / or handover. For example, the base station can indicate or assign a preamble to be used for Msg 1 1321 to the UE. The UE can receive an indication of the preamble (e.g., ra-PreambleIndex) from the base station via PDCCH and / or RRC. Figure 13B

[0185] ​After transmitting a preamble, the UE may start a time window (e.g., ra-ResponseWindow) to monitor the PDCCH of the RAR. In the case of a beam failure recovery request, the base station may configure the UE with a separate time window and / or a separate PDCCH in the search space indicated by an RRC message (e.g., recoverySearchSpaceId). The UE may monitor PDCCH transmissions addressed to the Cell RNTI (C-RNTI) on the search space. In Figure 13B In the contention-free random access procedure shown, the UE may determine that the random access procedure is successfully completed after the transmission of Msg 1 1321 and the reception of the corresponding Msg 2 1322 or in response to the transmission and the reception. For example, if the PDCCH transmission is addressed to the C-RNTI, the UE may determine that the random access procedure is successfully completed. For example, if the UE receives an RAR that includes a preamble identifier corresponding to the preamble transmitted by the UE and / or the RAR includes a MAC sub-PDU with a preamble identifier, the UE may determine that the random access procedure is successfully completed. The UE may determine that the response is an indication of an acknowledgement of the SI request.

[0186] Figure 13C Another two-step random access procedure is shown. Similar to Figure 13A and Figure 13B the random access procedure shown, the base station may transmit a configuration message 1330 to the UE before the procedure is initiated. The configuration message 1330 may be similar to the configuration message 1310 and / or the configuration message 1320 in some aspects. Figure 13C The procedure shown includes the transmission of two messages: Msg A 1331 and Msg B 1332.

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

[0188] The UE may initiate for licensed spectrum and / or unlicensed spectrumFigure 13C The two-step random access procedure in Figure 13C . The UE can determine whether to initiate the two-step random access procedure based on one or more factors. The one or more factors can be: the radio access technology being used (e.g., LTE, NR, etc.); whether the UE has a valid TA; cell size; the RRC state of the UE; the type of spectrum (e.g., licensed and unlicensed); and / or any other suitable factors.

[0189] The UE can determine the radio resources and / or uplink transmission power of the preamble 1341 and / or the transport block 1342 included in Msg A 1331 based on the two-step RACH parameters included in the configuration message 1330. The RACH parameters can indicate the modulation and coding scheme (MCS), time-frequency resources, and / or power control of the preamble 1341 and / or the transport block 1342. Time-frequency resources (e.g., PRACH) for the transmission of the preamble 1341 and time-frequency resources (e.g., PUSCH) for the transmission of the transport block 1342 can be multiplexed using FDM, TDM, and / or CDM. The RACH parameters can enable the UE to determine the reception timing and downlink channel for monitoring and / or receiving Msg B 1332.

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

[0191] The UE and the base station can exchange control signaling. The control signaling can be referred to as L1 / L2 control signaling and can originate from the PHY layer (e.g., layer 1) and / or the MAC layer (e.g., layer 2). The control signaling can include downlink control signaling transmitted from the base station to the UE and / or uplink control signaling transmitted from the UE to the base station.

[0192] Downlink control signaling may include: downlink scheduling assignment; uplink scheduling authorization indicating uplink radio resources and / or transmission format; slot format information; preemption indication; power control command; and / or any other suitable signaling. The UE may receive downlink control signaling in the payload transmitted by the base station on the physical downlink control channel (PDCCH). The payload transmitted on the PDCCH may be referred to as downlink control information (DCI). In some scenarios, the PDCCH may be a group common PDCCH (GC-PDCCH) common to a group of UEs.

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

[0194] The DCI may be used for different purposes. The purpose may be indicated by the type of RNTI used to scramble the CRC parity bits. For example, a DCI with CRC parity bits scrambled with a paging RNTI (P-RNTI) may indicate paging information and / or a system information change notification. The P-RNTI may be predefined as hexadecimal "FFFE". A DCI with CRC parity bits scrambled with a system information RNTI (SI-RNTI) may indicate the broadcast transmission of system information. The SI-RNTI may be predefined as hexadecimal "FFFF". A DCI with CRC parity bits scrambled with a random access RNTI (RA-RNTI) may indicate a random access response (RAR). A DCI with CRC parity bits scrambled with a cell RNTI (C-RNTI) may indicate a dynamically scheduled unicast transmission and / or the triggering of PDCCH-ordered random access. A DCI with CRC parity bits scrambled with a temporary cell RNTI (TC-RNTI) may indicate contention resolution (e.g., similar to Figure 13AMsg 3 of the shown Msg 3 1313). Other RNTIs configured by the base station for the UE may include: the configured scheduling RNTI (CS-RNTI), the transmission power control PUCCH RNTI (TPC-PUCCH-RNTI), the transmission power control PUSCH RNTI (TPC-PUSCH-RNTI), the transmission power control SRS RNTI (TPC-SRS-RNTI), the interruption RNTI (INT-RNTI), the time slot format indication RNTI (SFI-RNTI), the semi-persistent CSI RNTI (SP-CSI-RNTI), the modulation and coding scheme cell RNTI (MCS-C-RNTI), etc.

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

[0196] After scrambling the DCI with an RNTI, the base station can process the DCI with channel coding (e.g., polar coding), rate matching, scrambling, and / or QPSK modulation. The base station can map the coded and modulated DCI on the resource elements used for and / or configured for the PDCCH. Based on the payload size of the DCI and / or the coverage area of the base station, the base station can transmit the DCI via a PDCCH that occupies multiple consecutive control channel elements (CCEs). The number of consecutive CCEs (referred to as the aggregation level) can be 1, 2, 4, 8, 16, and / or any other suitable number. A CCE can include a number of resource element groups (REGs) (e.g., 6). A REG can include resource blocks in an OFDM symbol. The mapping of the coded and modulated DCI on the resource elements can be based on the mapping of CCEs and REGs (e.g., CCE-to-REG mapping).

[0197] Figure 14A An example of a CORESET configuration for a bandwidth part is shown. The base station can transmit the DCI via a PDCCH on one or more control resource sets (CORESETs). A CORESET can include time-frequency resources in which the UE attempts to decode the DCI using one or more search spaces. The base station can configure the CORESET in the time-frequency domain. In Figure 14A the example, a first CORESET 1401 and a second CORESET 1402 appear at the first symbol in a time slot. The first CORESET 1401 overlaps with the second CORESET 1402 in the frequency domain. A third CORESET 1403 appears at the third symbol in the time slot. A fourth CORESET 1404 appears at the seventh symbol in the time slot. The CORESETs can have different numbers of resource blocks in the frequency domain.

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

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

[0200] As Figure 14B shown, the UE may determine the time-frequency resources of the CORESET based on the RRC message. The UE may determine the CCE-to-REG mapping (e.g., interleaved or non-interleaved and / or mapping parameters) of the CORESET based on the configuration parameters of the CORESET. The UE may determine the number of search space sets configured on the CORESET (e.g., up to 10) based on the RRC message. The UE may monitor the set of PDCCH candidates according to the configuration parameters of the search space set. The UE may monitor the set of PDCCH candidates in one or more CORESETs for detecting one or more DCIs. The monitoring may include decoding one or more PDCCH candidates in the set of PDCCH candidates according to the monitored DCI format. The monitoring may include decoding the DCI content of one or more PDCCH candidates, which has possible (or configured) PDCCH positions, possible (or configured) PDCCH formats (e.g., the number of CCEs, the number of PDCCH candidates in the common search space, and / or the number of PDCCH candidates in the UE-specific search space), and possible (or configured) DCI formats. The decoding may be referred to as blind decoding. The UE may determine that the DCI is valid for the UE in response to a CRC check (e.g., the scrambled bits of the CRC parity bits of the DCI that match the RNTI value). The UE may process the information contained in the DCI (e.g., scheduling assignment, uplink grant, power control, slot format indication, downlink preemption, etc.).

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

[0202] There can be five PUCCH formats, and the UE can determine the PUCCH format based on the size of the UCI (e.g., the number of uplink symbols for the UCI transmission and the number of UCI bits). PUCCH format 0 can have a length of one or two OFDM symbols and can include two or fewer bits. If the transmission is more than one or two symbols and the number of HARQ-ACK information bits (HARQ-ACK / SR bits) with a positive or negative SR is one or two, the wireless device can use PUCCH format 0 to transmit the UCI in the PUCCH resource. PUCCH format 1 can occupy a number between four and fourteen OFDM symbols and can include two or fewer bits. If the transmission is four or more symbols and the number of HARQ-ACK / SR bits is one or two, the UE can use PUCCH format 1. PUCCH format 2 can occupy one or two OFDM symbols and can include more than two bits. If the transmission is more than one or two symbols and the number of UCI bits is two or more, the UE can use PUCCH format 2. PUCCH format 3 can occupy a number between four and fourteen OFDM symbols and can include more than two bits. If the transmission is four or more symbols, the number of UCI bits is two or more, and the PUCCH resource does not include an orthogonal cover code, the UE can use PUCCH format 3. PUCCH format 4 can occupy a number between four and fourteen OFDM symbols and can include more than two bits. 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, the UE can use PUCCH format 4.

[0203] The base station may transmit configuration parameters of multiple PUCCH resource sets to the UE using, for example, RRC messages. The multiple PUCCH resource sets (e.g., up to four sets) may be configured on the uplink BWP of the cell. A PUCCH resource set may be configured with: a PUCCH resource set index; multiple PUCCH resources having PUCCH resources identified by PUCCH resource identifiers (e.g., pucch-Resourceid); and / or multiple (e.g., a maximum number of) UCI information bits that the UE may transmit using one of the multiple PUCCH resources in the PUCCH resource set. When multiple PUCCH resource sets are configured, the UE may select one PUCCH resource set (e.g., HARQ-ACK, SR, and / or CSI) from the multiple PUCCH resource sets based on the total bit length of the UCI information bits. If the total bit length of the UCI information bits is two or less, the UE may select a first PUCCH resource set having a PUCCH resource set index equal to "0". If the total bit length of the 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 the 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 the 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 the PUCCH resource set from the multiple PUCCH resource sets, the UE may determine a PUCCH resource for UCI (HARQ-ACK, CSI, and / or SR) transmission from the PUCCH resource set. The UE may determine the PUCCH resource based on a PUCCH resource indicator in DCI received on the PDCCH (e.g., DCI having format 1_0 or DCI for 1_1). The three-bit PUCCH resource indicator in the DCI may indicate one of the eight PUCCH resources in the PUCCH resource set. Based on the PUCCH resource indicator, the UE may use the PUCCH resource indicated by the PUCCH resource indicator in the DCI to transmit UCI (HARQ-ACK, CSI, and / or SR).

[0205] Figure 15 An example of a wireless device 1502 communicating with a base station 1504 in accordance with an embodiment of the present disclosure is shown. The wireless device 1502 and the base station 1504 may be part of a mobile communication network, such as Figure 1A the mobile communication network 100 shown,Figure 1B The mobile communication network 150 or any other communication network shown. Figure 15 Only one wireless device 1502 and one base station 1504 are shown, but it should be understood that the mobile communication network may include more than one UE and / or more than one base station, which have the same or similar configurations as those Figure 15 shown.

[0206] The base station 1504 can connect the wireless device 1502 to the core network (not shown) through radio communication via the air interface (or radio interface) 1506. The communication direction from the base station 1504 to the wireless device 1502 through the air interface 1506 is called the downlink, while the communication direction from the wireless device 1502 to the base station 1504 through the air interface is called the uplink. The downlink transmission can be separated from the uplink transmission using FDD, TDD, and / or some combination of the two duplexing techniques.

[0207] In the downlink, the data to be sent from the base station 1504 to the wireless device 1502 can be provided to the processing system 1508 of the base station 1504. This data can be provided to the processing system 1508 through, for example, the core network. In the uplink, the data to be sent from the wireless device 1502 to the base station 1504 can be provided to the processing system 1518 of the wireless device 1502. The processing system 1508 and the processing system 1518 can implement layer 3 and layer 2 OSI functions to process the data for transmission. Layer 2 can include, for example, the SDAP layer, PDCP layer, RLC layer, and MAC layer regarding Figure 2A , Figure 2B , Figure 3 and Figure 4A . Layer 3 can include the RRC layer regarding Figure 2B .

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

[0209] At base station 1504, receive processing system 1512 can receive an uplink transmission from wireless device 1502. At wireless device 1502, receive processing system 1522 can receive a downlink transmission from base station 1504. Receive processing system 1512 and receive processing system 1522 can implement layer 1 OSI functions. Layer 1 can include with respect to Figure 2A , Figure 2B , Figure 3 and Figure 4A of the PHY layer. For receive processing, the PHY layer can 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, etc.

[0210] As Figure 15 shown, wireless device 1502 and base station 1504 can include multiple antennas. The multiple antennas can be used to perform one or more MIMO or multi-antenna techniques, such as spatial multiplexing (e.g., single-user MIMO or multi-user MIMO), transmit / receive diversity, and / or beamforming. In other examples, wireless device 1502 and / or base station 1504 can have a single antenna.

[0211] Processing system 1508 and processing system 1518 can be associated with memory 1514 and memory 1524, respectively. Memory 1514 and memory 1524 (e.g., one or more non-transitory computer-readable media) can store computer program instructions or code that can be executed by processing system 1508 and / or processing system 1518 to perform one or more of the functions discussed in this application. Although Figure 15 not shown, transmit processing system 1510, transmit processing system 1520, receive processing system 1512, and / or receive processing system 1522 can be coupled to a memory (e.g., one or more non-transitory computer-readable media) that stores computer program instructions or code that can be executed to perform one or more of their respective functions.

[0212] Processing system 1508 and / or processing system 1518 may include one or more controllers and / or one or more processors. The one or more controllers and / or one or more processors may include, for example, a general-purpose processor, a digital signal processor (DSP), a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) and / or other programmable logic devices, discrete gates and / or transistor logic, discrete hardware components, on-board units, or any combination thereof. Processing system 1508 and / or processing system 1518 may perform at least one of the following: signal encoding / processing, data processing, power control, input / output processing, and / or any other function that enables wireless device 1502 and base station 1504 to operate in a wireless environment.

[0213] Processing system 1508 and / or processing system 1518 may be respectively connected to one or more peripheral devices 1516 and one or more peripheral devices 1526. The one or more peripheral devices 1516 and the one or more peripheral devices 1526 may include software and / or hardware that provide features and / or functions, such as speakers, microphones, keyboards, displays, touch pads, power supplies, satellite transceivers, universal serial bus (USB) ports, hands-free headsets, frequency modulation (FM) radio units, media players, Internet browsers, electronic control units (e.g., for motor vehicles), and / or one or more sensors (e.g., accelerometers, gyroscopes, temperature sensors, radar sensors, lidar sensors, ultrasonic sensors, light sensors, cameras, etc.). Processing system 1508 and / or processing system 1518 may receive user input data from the one or more peripheral devices 1516 and / or the one or more peripheral devices 1526 and / or provide user output data to the above-mentioned one or more peripheral devices. The processing system 1518 in the wireless device 1502 may receive power from a power supply and / or may be configured to distribute power to other components in the wireless device 1502. The power supply may include one or more power sources, such as batteries, solar cells, fuel cells, or any combination thereof. Processing system 1508 and / or processing system 1518 may be respectively connected to GPS chipset 1517 and GPS chipset 1527. GPS chipset 1517 and GPS chipset 1527 may be configured to provide the geographical location information of wireless device 1502 and base station 1504, respectively.

[0214] Figure 16AAn exemplary structure for uplink transmission is shown. The baseband signal representing the Physical Uplink Shared Channel may perform one or more functions. The one or more functions may include at least one of the following: scrambling; modulating the scrambled bits to generate complex-valued symbols; mapping the complex-valued modulation symbols to one or more transport layers; transform precoding to generate complex-valued symbols; precoding of the complex-valued symbols; mapping of the precoded complex-valued symbols to resource elements; generating a complex-valued time-domain single-carrier frequency-division multiple access (SC-FDMA) or CP-OFDM signal for an antenna port; and so on. In an example, when transform precoding is enabled, an 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 Figure 16A These functions are shown as examples, and it is expected that other mechanisms may be implemented in various embodiments.

[0215] Figure 16B An exemplary structure for modulating and up-converting the baseband signal to a carrier frequency is shown. The baseband signal may be a complex-valued SC-FDMA or CP-OFDM baseband signal of an antenna port and / or a complex-valued Physical Random Access Channel (PRACH) baseband signal. Filtering may be employed before transmission.

[0216] Figure 16C An exemplary structure for downlink transmission is shown. The baseband signal representing the Physical Downlink Channel may perform one or more functions. The one or more functions may include: scrambling the coded bits in the codeword to be transmitted on the physical channel; modulating the scrambled bits to generate complex-valued modulation symbols; mapping the complex-valued modulation symbols to one or more transport layers; precoding of the complex-valued modulation symbols on the layer for transmission on an antenna port; mapping the complex-valued modulation symbols for an antenna port to resource elements; generating a complex-valued time-domain OFDM signal for an antenna port; and so on. These functions are shown as examples, and it is expected that other mechanisms may be implemented in various embodiments.

[0217] Figure 16D Another exemplary structure for modulating and up-converting the baseband signal to a carrier frequency is shown. The baseband signal may be a complex-valued OFDM baseband signal of an antenna port. Filtering may be employed before transmission.

[0218] A wireless device can receive one or more messages (e.g., RRC messages) from a base station that include configuration parameters for multiple cells (e.g., a primary cell, a secondary cell). The wireless device can communicate with at least one base station (e.g., two or more base stations in dual connectivity) via the multiple cells. One or more messages (e.g., as part of the configuration parameters) can include parameters for configuring the wireless device for the physical layer, MAC layer, RLC layer, PCDP layer, SDAP layer, and RRC layer. For example, the configuration parameters can include parameters for configuring physical layer and MAC layer channels, bearers, etc. For example, the configuration parameters can include parameters indicating values of timers for the physical layer, MAC layer, RLC layer, PCDP layer, SDAP layer, RRC layer, and / or communication channels.

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

[0220] When an RRC connection has been established, the UE is in the RRC connected state. When no RRC connection is established, the UE is in the RRC idle state. When the RRC connection is suspended, the UE can be in the RRC inactive state. When the UE is in the RRC idle state, the UE can have a suspended RRC connection. Based on the suspended RRC connection in the RRC idle state, the UE is in the RRC idle state with a suspended RRC connection.

[0221] The RRC connection establishment may include the establishment of SRB1. The base station may complete the RRC connection establishment before completing the establishment of the S1 connection (e.g., before receiving the UE context information from the core network entity (e.g., AMF)). In the initial stage of the RRC connection, the access stratum (AS) security is not activated. In the initial stage of the RRC connection, the base station may configure the UE to perform measurement reporting. After the successful activation of the AS security, the UE may send the corresponding measurement report. When the AS security is activated, the UE may receive or accept a handover message (e.g., handover command).

[0222] After initiating the initial (AS) security activation procedure, the base station may initiate the establishment of SRB2 and DRB. For example, the base station may initiate the establishment of SRB2 and DRB before receiving the confirmation of the initial security activation from the UE. The base station may apply encryption and integrity protection to the RRC (connection) reconfiguration message, which is used to establish SRB2 and DRB. The base station may release the RRC connection based on the initial security activation and / or radio bearer establishment failure. For example, the security activation and DRB establishment may be triggered by a combined S1 procedure, where the combined S1 procedure may not support partial success. For SRB2 and DRB, the (AS) security may be activated from the beginning. For example, the base station may not establish these bearers before activating the security.

[0223] The base station may initiate the suspension of the RRC connection. When the RRC connection is suspended, the UE may store the UE AS context and the resume identity (or I-RNTI), and transition to the RRC_IDLE state. The RRC message for suspending the RRC connection is integrity protected and encrypted. The suspension may be performed when at least 1 DRB is successfully established. When the UE has the stored UE AS context, the UE (e.g., UE-NAS layer) initiates the resume of the suspended RRC connection, the base station allows the RRC connection to resume, and the UE needs to transition from the RRC idle state to the RRC connected state. When resuming the RRC connection, the UE (UE-RRC layer) may configure the UE according to the RRC connection resume procedure based on the stored UE AS context and the RRC configuration received from the base station. The RRC connection resume procedure may reactivate the (AS) security and reconstruct the SRB and DRB. The request for resuming the RRC connection (e.g., RRC resume request message) may include the resume identity. This request may not be encrypted and protected with a message authentication code.

[0224] In response to the request for resuming the RRC connection, the base station (or core network entity) may resume the suspended RRC connection, reject the resume request, and instruct the UE to retain or discard the stored context, or establish a new RRC connection.

[0225] For CP transmission based on CP EDT or using PUR (e.g., CP small data transmission), data can be appended to the RRC early data request and RRC early data completion messages and sent via SRB0. For UP transmission based on UP EDT or using PUR (e.g., UP small data transmission), the next-hop link count provided in the RRC (connection) release message with a suspension indication (e.g., suspension configuration parameter) during a previous suspension procedure can be used to reactivate (AS) security before transmitting RRC messages, and radio bearers can be re-established. Uplink data can be encrypted and transmitted on the DTCH multiplexed with the RRC (connection) resume request message on the CCCH. In the downlink, data can be transmitted on the DTCH multiplexed with the RRC (connection) release message on the DCCH. In response to an EDT request or a transmission using PUR (e.g., small data transmission), the base station can also choose to establish or resume an RRC connection.

[0226] When the base station indicates RRC connection suspension in the RRC release message, a UE in the RRC connected state can transition to the RRC inactive state. When transitioning to the RRC inactive state, the UE can store the UE inactive AS context and the RRC configuration received from the base station. When the UE needs to transition from the RRC inactive state to the RRC connected state, the recovery of the RRC connection from the RRC inactive state can be initiated by the UE (e.g., UE-NAS layer), or the recovery of the RRC connection from the RRC inactive state can be initiated by the UE (e.g., UE-RRC layer) for receiving a RAN-based notification area update (RNAU) or RAN paging. When resuming the RRC connection, the base station can configure the UE according to the RRC connection resume procedure based on the stored UE inactive AS context and the RRC configuration received from the base station. The RRC connection resume procedure can reactivate (AS) security and re-establish SRBs and DRBs. In response to a request to resume the RRC connection from the RRC inactive state, the base station can resume the suspended RRC connection, and the UE can transition to the RRC connected state. In response to a request to resume the RRC connection from the RRC inactive state, the base station can reject the request to resume using the RRC message without security protection and send the UE to the RRC inactive state with a waiting time, or directly re-suspend the RRC connection and put the UE into the RRC inactive state, or directly release the RRC connection and put the UE into the RRC idle state, or indicate that the UE initiates a NAS-level restoration. Based on the NAS-level restoration, the UE can send a NAS message (e.g., registration update message) to the AMF.

[0227] When receiving the UE context from a core network entity (e.g., AMF), the base station may use the initial security activation procedure to activate (AS) security (encryption and integrity protection). The RRC messages for activating security (commands and successful responses) may be integrity protected. Encryption may only start after the initial security activation procedure is completed. For example, the response to the RRC message used to activate security may not be encrypted. Subsequent messages (e.g., for establishing SRB2 and DRB) may be integrity protected and encrypted.

[0228] The UE-RRC layer may initiate an RRC connection establishment procedure, an RRC connection recovery procedure, or an RRC connection reestablishment procedure. Based on initiating the RRC connection establishment procedure or the RRC connection recovery procedure, the UE may perform one or more procedures, where the one or more procedures include at least one of the following: performing a unified access control procedure (e.g., access prohibition check) on the access attempt for the RRC establishment / recovery procedure on the serving cell; applying the default configuration parameters and the configuration / parameters provided by SIB1 (e.g., based on the allowed access attempt, applying the default configuration and the configuration / parameters provided by SIB1); for example, based on the allowed access attempt, performing sending a random access preamble to the serving cell; sending an RRC request message to the serving cell (e.g., based on determining the successful reception of the random access response, sending an RRC request message to serving cell 0; starting a timer based on sending the RRC request message; receiving an RRC response message or an RRC rejection message from the serving cell (e.g., in response to the RRC request message); or sending an RRC completion message (e.g., in response to receiving the RRC response message, sending an RRC completion message). For the RRC connection reestablishment procedure, the UE may not perform a unified access procedure (e.g., access prohibition check) on the access attempt for the RRC reestablishment procedure.

[0229] A base station (e.g., NG-RAN) may support overload and access control functions, such as RACH backoff, RRC connection rejection, RRC connection release, and UE-based access prohibition mechanisms. The unified access control framework applies to all UE states (e.g., RRC idle, inactive, and connected states). The base station may broadcast prohibition control information associated with access categories and access identifiers (in the case of network sharing, the prohibition control information may be set separately for each PLMN). The UE may determine whether an access attempt is authorized based on the prohibition information broadcast of the selected PLMN, the selected access category, and the access identifier of the access attempt. For NAS-triggered requests, the UE-NAS layer may determine the access category and the access identifier. For AS-triggered requests, the UE-RRC layer determines the access category, and the NAS determines the access identifier. The base station may process access attempts with high-priority establishment reasons "emergency", "mps priority access", and "mcs priority access" (i.e., emergency calls, MPS, MCS subscribers), and respond to these access attempts with RRC rejection only under extreme network load conditions that may threaten the stability of the base station.

[0230] Based on initiating an RRC connection establishment procedure or an RRC connection resume procedure, a UE in the RRC inactive or idle state can perform or initiate an access prohibition check (or unified access control procedure) for an access attempt of the RRC connection establishment procedure or the RRC connection resume procedure. Based on performing or initiating the access prohibition check, the UE can determine the access category and access identifier of the access attempt. The UE can determine that the access attempt is prohibited based on at least one of the following: the timer T309 is running for the access category of the access attempt; and the timer T302 is running and the access category is neither '2' nor '0'. The UE can determine an allowed access attempt based on at least one of the following: the access category is '0'; and the system information block (system information block type 25) including the unified access control (UAC) prohibition parameter is not broadcast by the serving cell. The UE can determine that the access attempt is prohibited based on at least one of the following: the establishment cause (e.g., for the access attempt) is not an emergency; the access prohibition of each RSRP parameter of the system information block includes (or is set to) a threshold of 0 and the wireless device is in enhanced coverage; the access prohibition of each RSRP parameter of the system information block includes (or is set to) a threshold of 1 and the measured RSRP is less than the first entry in the RSRP threshold PRACH information list; the access prohibition parameter of each RSRP of the system information block includes (or is set to) a threshold of 2 and the measured RSRP is less than the second entry in the RSRP threshold PRACH information list; and the access prohibition of each RSRP parameter of the system information block includes (or is set to) a threshold of 3 and the measured RSRP is less than the third entry in the RSRP threshold PRACH information list. The UE can determine that the access attempt is allowed based on the system information block not including the UAC prohibition parameter for the access attempt. For example, the UE can determine that the access attempt is allowed based on the system information block not including the UAC prohibition parameter of the PLMN selected by the UE and the common UAC prohibition parameter. The UE can determine that the access attempt is allowed based on the common UAC prohibition parameter not including the access category of the access attempt. The UAC prohibition parameter can include at least one of the following: the UAC prohibition parameter per PLMN; and the UAC prohibition parameter. The UE can perform an access prohibition check on the access category of the access attempt based on the UAC prohibition parameter in the system information block. The UE can determine that the access attempt is allowed based on at least one of the corresponding bits of at least one access identifier in the access identifier in the UAC prohibition parameter being zero. The UE can extract a first random number uniformly distributed within a range, where the range is greater than or equal to 0 and less than 1. The UE can determine that the access attempt is allowed based on the first random number being lower than the UAC prohibition factor in the UAC prohibition parameter. The UE can determine that the access attempt is prohibited based on the first random number being greater than the UAC prohibition factor in the UAC prohibition parameter.In response to determining that an access attempt is prohibited, the UE may draw a second random number that is uniformly distributed within a range that is greater than or equal to 0 and less than 1. The UE may start a barring timer T309 for the access category based on the second random number. When the barring timer T309 is running, access attempts associated with the access category are prohibited (e.g., transmissions are not allowed). Based on the expiration of the barring timer T309, the UE may consider the barring of the access category to be alleviated. Based on the alleviation of the barring of the access category, if the UE has an access attempt for the access category, the UE may perform an access barring check for the access category.

[0231] Based on initiating an RRC connection reestablishment procedure, if one or more barring timers T309 are running, the UE may stop one or more barring timers T309 for all access categories. Based on stopping one or more barring timers T309, the UE may determine that the barring for all access categories is being alleviated. The UE may perform the RRC connection reestablishment procedure based on the alleviation of the barring for all access categories. For example, based on the alleviation of the barring for all access categories, the UE may send an RRC reestablishment request without barring.

[0232] To initiate an RRC connection establishment / resumption / reestablishment procedure, the UE-RRC layer may use the parameters in the received SIB1. The UE-RRC layer may use the L1 parameter values and the timing alignment timer in SIB1. The UE-RRC layer may use the UAC barring information in SIB1 to perform a unified access control procedure. Based on the unified access control procedure, the UE-RRC layer may determine whether access attempts for these RRC procedures are prohibited or allowed. Based on determining that the access attempt is allowed, the UE-RRC layer may determine to send an RRC request message to the base station, where the RRC request message may be an RRC establishment request message, an RRC resume request message, or an RRC reestablishment message. The UE-NAS layer may or may not provide the S-TMSI as the UE identifier. The UE-RRC layer may set the UE identifier in the RRC request message.

[0233] For an RRC setup request message, a UE in the RRC idle state can initiate an RRC connection establishment procedure. Based on initiating the RRC connection establishment procedure, if the UE-NAS layer provides an S-TMSI, the UE-RRC layer of the UE in the RRC idle state can set the UE identifier to the S-TMSI. Otherwise, the UE-RRC layer of the UE in the RRC idle state can extract a 39-bit random value and set the UE identifier to that random value. For an RRC resume request message, the UE-RRC layer of the UE in the RRC inactive or idle state can set the UE identifier to the resumed stored identifier. For an RRC reestablishment request message, the UE-RRC layer of the UE in the RRC connected state can set the UE identifier to the C-RNTI used in the source PCell. The UE-NAS layer can provide the establishment cause (e.g., the UE-NAS layer). The UE-RRC layer can set the establishment cause of the RRC request message.

[0234] For an RRC Resume Request message, a UE in RRC Inactive state can initiate an RRC connection resume procedure. A UE in RRC Idle state with a suspended RRC connection can initiate an RRC connection resume procedure. A UE in RRC Inactive or Idle state can initiate an RRC connection procedure based on at least one of the following: resuming (suspending) the RRC connection; and performing / initiating UP small data transfer. Based on initiating the RRC connection resume procedure, the UE-RRC layer can restore the stored configuration parameters and the stored security keys from the stored UE Inactive AS context. Based on the security key, the UE-RRC layer in RRC Inactive or Idle state can set the resumed MAC-I value to the 16 least significant bits of the MAC-I calculated based on a variable resume MAC input, the security key for integrity protection of the RRC layer in the UE Inactive AS context, the previously configured integrity protection algorithm, and other security parameters (e.g., count, bearer, and direction). The variable resume MAC input can include at least one of the following: the physical cell identity of the source cell; the C-RNTI of the source cell; and the cell identity of the target cell (e.g., the selected cell), where the cell identity is the cell identity in the system information block (e.g., SIB1) of the target cell (e.g., the selected cell). Based on the security key and the Next Hop Link Count (NCC) value, the UE-RRC layer in RRC Inactive or Idle state derives new security keys for integrity protection and encryption and configures the lower layers (e.g., the UE-PDCP layer) to apply them. The UE can have a stored NCC value and a resume identity. The UE can receive an RRC Release message with a suspend indication (or suspend configuration parameters), where the RRC Release message includes at least one of the following: a resume identity; and an NCC value. The UE-RRC layer in RRC Inactive or Idle state can re-establish PDCP entities for one or more bearers. The UE-RRC layer can resume one or more bearers. For example, based on resuming the RRC connection, the UE-RRC layer can resume SRB1. Based on performing UP small data transfer, the UE-RRC layer can resume one or more SRBs and DRBs. The UE-RRC layer in RRC Inactive or Idle state can send an RRC Resume Request message to the base station, where the RRC Resume Request message can include at least one of the following: a resume identity; a resumed MAC-I; and a resume reason.

[0235] For an RRC Reestablishment Request message, a UE in the RRC connected state can initiate an RRC connection reestablishment procedure. Based on initiating the RRC connection reestablishment procedure, the UE-RRC layer of a UE in the RRC connected state can include the physical cell identity of the source PCell and the short MAC-I in the RRC reestablishment message. The UE-RRC layer of a UE in the RRC connected state can set the short MAC-I to the 16 least significant bits of the MAC-I calculated based on a variable short MAC input, the security key for integrity protection of the RRC layer, and the integrity protection algorithm (which is used in the source PCell or the PCell in which the reestablishment trigger occurred), and other security parameters (e.g., count, bearer, and direction). The variable short MAC input can include at least one of the following: the physical cell identity of the source cell; the C-RNTI of the source cell; and the cell identity of the target cell (e.g., the selected cell), where the cell identity is the cell identity in the system information block (e.g., SIB1) of the target cell (e.g., the selected cell). The UE-RRC layer of a UE in the RRC connected state can re-establish the PDCP entity and the RLC entity for SRB1 and apply the default SRB1 configuration parameters for SRB1. The UE-RRC layer of a UE in the RRC connected state can configure the lower layer (e.g., the PDCP layer) to suspend the integrity protection and encryption of SRB1 and resume SRB1.

[0236] The UE-RRC layer can send an RRC request message for transmission to the lower layer (e.g., the PDCP layer, the RLC layer, the MAC layer, and / or the PHY layer), where the RRC request message can be an RRC setup request message, an RRC resume request message, or an RRC reestablishment message.

[0237] The UE-RRC layer can receive an RRC establishment message in response to an RRC resume request message or an RRC reestablishment request message. Based on the RRC setup message, the UE-RRC layer can discard any stored AS context, suspended configuration parameters, and the current AS security context. The UE-RRC layer can release the radio resources of all established RBs except SRB0, including releasing the associated PDCP entity and the RLC entity of the SDAP. The UE-RRC layer can release the RRC configuration except for the default L1 parameter values, the default MAC cell group configuration, and the CCCH configuration. The UE-RRC layer can indicate a fallback of the RRC connection to the upper layer (e.g., the NAS layer). If operating in the case where the timer T380 is a periodic RAN-based notification area (RNA) update timer, the UE-RRC layer can stop the timer T380.

[0238] The UE-RRC layer may receive an RRC setup message in response to an RRC setup request message, an RRC resume request message, or an RRC reestablishment request message. The RRC setup message may include cell group configuration parameters and radio bearer configuration parameters. The radio bearer configuration parameters may include at least one of signaling radio bearer configuration parameters, data radio bearer configuration parameters, and / or security configuration parameters. The security configuration parameters may include security algorithm configuration parameters and a key usage indication that indicates whether the radio bearer configuration parameters are to use the master key or the secondary key. The signaling radio bearer configuration parameters may include one or more signaling radio bearer configuration parameters. Each signaling radio configuration parameter may include at least one of an srb identifier, PDCP configuration parameters, a reestablish PDCP indication, and / or a discard PDCP indication. The data radio bearer configuration parameters may include one or more data radio bearer configuration parameters. Each data radio configuration parameter may include at least one of a drb identifier, PDCP configuration parameters, SDAP configuration parameters, a reestablish PDCP indication, and / or a resume PDCP indication. The radio bearer configuration in the RRC setup message may include signaling radio configuration parameters for SIB1. Based on the RRC setup message, the UE-RRC layer may establish SRB1. Based on the RRC setup message, the UE-RRC layer may perform cell group configuration or radio bearer configuration. The UE-RRC layer may cause the prohibition timer and the wait timer to stop to facilitate the cell to send the RRC setup message. Based on receiving the RRC setup message, the UE-RRC layer may perform one or more of the following: transition to the RRC connected state; stop the cell reselection process; consider the current cell that sent the RRC setup message as the PCell and / or send an RRC setup complete message by setting the content of the RRC setup complete message.

[0239] The UE-RRC layer may receive an RRC resume message in response to an RRC resume request message. Based on the RRC resume message, the UE-RRC layer may discard the UE inactive AS context and release the suspended configuration parameters except for the ran notification area information. Based on the configuration parameters in the RRC resume message, the UE-RRC layer may perform cell group configuration, radio bearer configuration, a security key update process, and a measurement configuration process. Based on receiving the RRC resume message, the UE-RRC layer may perform one or more of the following: indicate to the upper layer (e.g., the NAS layer) that the suspended RRC connection has been resumed; resume SRB2, all DRBs, and measurements; enter the RRC connected state; stop the cell reselection process; consider the current cell that sent the RRC resume message as the PCell and / or send an RRC resume complete message by setting the content of the RRC resume complete message.

[0240] The cell group configuration parameters may include at least one of the RLC bearer configuration parameters of the first cell group, the MAC cell group configuration parameters, the physical cell group configuration parameters, the SpCell configuration parameters, or the SCell configuration parameters of other cells of the second base station. The SpCell configuration parameters may include at least one of a radio link failure timer and constraints, radio link monitoring of synchronization out-of-synchronization thresholds, and / or service cell configuration parameters of the first cell. The service cell configuration parameters may include at least one of the following: downlink BWP configuration parameters; uplink configuration parameters; uplink configuration parameters of a supplementary uplink carrier (SUL); PDCCH parameters applicable to all BWPs of the service cell; PDSCH parameters applicable to all BWPs of the service cell; CSI measurement configuration parameters; SCell deactivation timer; cross-carrier scheduling configuration parameters of the service cell; timing advance group (TAG) identifier (ID) of the service cell; path loss reference link indicating whether the UE should use the downlink of the SpCell or the SCell as the path loss reference for the uplink; service cell measurement configuration parameters; channel access configuration parameters of the access procedure for shared spectrum channel access operations.

[0241] The CSI measurement configuration parameters may be to configure CSI-RS (reference signal) belonging to the service cell, configure channel state information reporting of CSI-RS (reference signal) belonging to the service cell, and channel state information reporting on the PUSCH triggered by DCI received on the service cell.

[0242] In an example, the downlink BWP configuration parameters may be used to configure dedicated (UE-specific) parameters of one or more downlink BWPs. The one or more downlink BWPs may include at least one of an initial downlink BWP, a default downlink BWP, and a first active downlink BWP. The downlink BWP configuration parameters may include at least one of the following: configuration parameters for one or more downlink BWPs; one or more downlink BWP IDs for one or more downlink BWPs; and a BWP inactivity timer. The configuration parameters of the downlink BWP may include at least one of the following: PDCCH configuration parameters for the downlink BWP; PDSCH configuration parameters for the downlink BWP; semi-persistent scheduling (SPS) configuration parameters for the downlink BWP; beam failure recovery SCell configuration parameters of candidate RSs; and / or radio link monitoring configuration parameters for detecting cell and beam radio link failure instances of the downlink BWP. The one or more downlink BWP IDs may include at least one of an initial downlink BWP ID, a default downlink BWP identifier (ID), and a first active downlink BWP ID.

[0243] In an example, the uplink configuration parameter may be an uplink configuration parameter for a normal uplink carrier (not a supplementary uplink carrier). The uplink configuration parameter (or the uplink configuration parameter for SUL) may be used to configure dedicated (UE-specific) parameters for one or more uplink BWPs. One or more uplink BWPs may include at least one of an initial uplink BWP and a first active uplink BWP. The uplink BWP configuration parameter may include at least one of the following: configuration parameters for one or more uplink BWPs; one or more uplink BWP IDs for one or more uplink BWPs; PUSCH parameters common to the BWPs of the UE in the serving cell; SRS carrier switching information; and power control configuration parameters. The configuration parameters for the uplink BWP may include at least one of the following: one or more PUCCH configuration parameters for the uplink BWP; PUSCH configuration parameters for the uplink BWP; one or more configured grant configuration parameters for the uplink BWP; SRS configuration parameters for the uplink BWP; beam failure recovery configuration parameters for the uplink BWP; and / or cyclic prefix (CP) extension parameters for the uplink BWP.

[0244] One or more uplink BWP IDs may include at least one of an initial uplink BWP ID (e.g., initial uplink BWP ID = 0) and / or a first active uplink BWP ID. The SRS carrier switching information may be used to configure SRS carrier switching when PUSCH is not configured, and SRS power control independent of PUSCH. The power control configuration parameter may include at least one of the power control configuration parameter for PUSCH, the power configuration control parameter for PUCCH, and the power control parameter for SRS.

[0245] The UE-RRC layer in the RRC inactive or idle state may receive an RRC reject message in response to an RRC establishment request message or an RRC resume request message. The RRC reject message may contain a wait timer. Based on the wait timer, the UE-RRC layer may start timer T302, where the timer value is set to the wait timer. Based on the RRC reject message, the UE-RRC layer may notify the upper layer (e.g., the UE-NAS layer) about the failure to set up an RRC connection or resume an RRC connection. The UE-RRC layer may reset the MAC and release the default MAC cell group configuration. Based on the RRC reject received in response to a request from the upper layer, the UE-RRC layer may notify the upper layer (e.g., the NAS layer) that access prohibition applies to all access categories except categories '0' and '2'.

[0246] The UE-RRC layer in the RRC inactive or idle state can receive an RRC rejection message in response to an RRC resume request message. Based on the RRC rejection message, the UE-RRC layer can discard the current security key. The UE-RRC layer can re-suspend the RRC connection. If the resume is triggered due to an RNA update, the UE-RRC layer can set the pending rna update value to true.

[0247] The UE-RRC layer in the RRC inactive or idle state can perform a cell (re)selection procedure while performing an RRC procedure to establish an RRC connection. Based on cell selection or cell reselection, the UE-RRC layer can change the cell on which the UE camps and stop the RRC procedure. The UE-RRC layer can notify the upper layer (e.g., the NAS layer) about the failure of the RRC procedure.

[0248] A UE in the RRC idle or RRC inactive state can perform one of two procedures (such as initial cell selection and cell selection) by using stored information. When the UE has not stored the cell information of the selected PLMN, the UE can perform initial cell selection. Otherwise, the UE can perform cell selection by using the stored information. For initial cell selection, the UE can scan all RF channels in the NR band according to its ability to find a suitable cell. Based on the result of the scan, the UE can search for the strongest cell on each frequency. The UE can select the cell as a suitable cell. For cell selection by using stored information, the UE may require the stored frequency information, and optionally also the information about cell parameters from the previously received measurement control information element or from the previously detected cell. Based on the stored information, if the UE finds a suitable cell, the UE can search for and select the suitable cell. If the UE does not find a suitable cell, the UE can perform initial cell selection.

[0249] The base station can configure the cell selection criteria for cell selection. The UE can seek to identify a suitable cell for cell selection. A suitable cell is a cell that satisfies the following conditions: (1) the measured cell attributes meet the cell selection criteria, (2) the cell PLMN is the selected PLMN, a registered or equivalent PLMN, (3) the cell is not prohibited or reserved, and (4) the cell is not part of a tracking area in the "roaming prohibited tracking area" list. The RRC layer in the UE can notify the NAS layer in the UE about the cell selection and reselection results based on the change of the received system information related to the NAS. For example, the cell selection and reselection results can be the cell identifier, the tracking area code, and the PLMN identifier.

[0250] A UE in the RRC connected state can detect a connection failure with the base station. A UE in the RRC connected state can activate AS security with the base station before detecting the failure. The failure includes at least one of the following: radio link failure (RLF), reconfiguration failure of synchronization, mobility failure from New Radio (NR), integrity check failure indication of Signaling Radio Bearer 1 (SRB1) or Signaling Radio Bearer 2 (SRB2) from a lower layer (e.g., PDCP layer), or RRC connection reconfiguration failure.

[0251] The radio link failure can be a radio link failure of the primary cell of the base station. The base station can send a reconfiguration of synchronization to the UE in the RRC connected state in an RRC message. The reconfiguration of synchronization can include reconfiguring a timer (e.g., T304). Based on receiving the reconfiguration of synchronization, the UE can start the reconfiguration timer and perform the reconfiguration of synchronization (e.g., handover). Based on the expiration of the reconfiguration timer, the UE determines that the reconfiguration of synchronization fails. The base station can send mobility from an NR command message to the UE in the RRC connected state. Based on receiving the mobility from the NR command message, the UE can perform a handover from NR to a cell using another RAT (e.g., E-UTRA). The UE can determine a mobility failure from NR based on satisfying at least one of the conditions: if the UE fails to successfully establish a connection to the target radio access technology; or if the UE cannot comply with any part of the configuration included in the mobility from the NR command message; or if there is a protocol error in the inter-RAT information included in the mobility from the NR message.

[0252] Based on detecting the failure, a UE in the RRC connected state can initiate an RRC connection reconstruction procedure. Based on initiating the RRC connection reconstruction procedure, the UE can start timer T311, pause all radio bearers except SRB0, and reset the MAC (layer). Based on initiating the RRC connection reconstruction procedure, a UE in the RRC connected state can release the MCG SCell, release the special cell (SpCell) configuration parameters and the multi-radio dual-connection (MR-DC) related configuration parameters. For example, based on initiating the RRC connection reconstruction procedure, the UE can release the primary cell group configuration parameters.

[0253] The cell group configuration parameters can be used to configure the master cell group (MCG) or the secondary cell group (SCG). If the cell group configuration parameters are used to configure the MCG, the cell group configuration parameters are the master cell group configuration parameters. If the cell group configuration parameters are used to configure the SCG, the cell group configuration parameters are the secondary cell group configuration parameters. A cell group includes a MAC entity, a set of logical channels with associated RLC entities, a primary cell (SpCell), and one or more secondary cells (SCells). The cell group configuration parameters (e.g., the master cell group configuration parameters or the secondary cell group configuration parameters) can include at least one of the RLC bearer configuration parameters of the cell group, the MAC cell group configuration parameters of the cell group, the physical cell group configuration parameters of the cell group, the SpCell configuration parameters of the cell group, or the SCell configuration parameters of the cell group. The MAC cell group configuration parameters can include the MAC parameters of the cell group, where the MAC parameters can include at least the DRX parameters. The physical cell group configuration parameters can include cell group-specific L1 (layer 1) parameters.

[0254] The special cell (SpCel) can include the primary cell (PCell) of the MCG or the primary SCG cell (PSCell) of the SCG. The SpCell configuration parameters can include the serving cell-specific MAC and PHY parameters of the SpCell. The MR-DC configuration parameters can include at least one of the SRB3 configuration parameters, the measurement configuration parameters of the SCG, and the SCG configuration parameters.

[0255] Based on initiating the RRC connection reestablishment procedure, a UE in the RRC connected state can perform a cell selection procedure. Based on the cell selection procedure, the UE can select a cell based on the signal quality of the cell exceeding a threshold. A UE in the RRC connected state can select a cell based on the signal quality of the cell exceeding a threshold. The UE can determine that the selected cell exceeds the threshold based on the cell selection procedure. The signal quality includes at least one of the following: reference signal received power; received signal strength indicator; reference signal received quality; or signal-to-interference-plus-noise ratio.

[0256] Based on selecting a suitable cell, a UE in the RRC connected state can stop timer 311 and start timer T301. Based on selecting a suitable cell, a UE in the RRC connected state can stop the barred timer T390 for all access categories. Based on stopping the barred timer T390, a UE in the RRC connected state can consider alleviating the barring for all access categories for the cell. Based on selecting a cell, a UE in the RRC connected state can apply the default L1 parameter values in addition to the parameters provided in SIB1, apply the default MAC cell group configuration, apply the CCCH configuration, apply the timer alignment timer in SIB1, and initiate the transmission of an RRC reestablishment request message.

[0257] A UE in the RRC connected state may stop timer T301 based on the reception of an RRC response message in response to an RRC reestablishment request message. The RRC response message may include at least one of an RRC reestablishment message, an RRC setup message, or an RRC reestablishment rejection message. When the selected cell becomes inappropriate, a UE in the RRC connected state may stop timer T301.

[0258] Based on the cell selection procedure triggered by initiating an RRC connection reestablishment procedure, a UE in the RRC connected state may select an inter-RAT cell. Based on selecting an inter-RAT cell, a UE in the RRC connected state (UE-AS layer) may transition to the RRC IDLE state and may provide the release cause 'RRC connection failure' to the upper layer (UE-NAS layer) of the UE.

[0259] Based on the transmission of an RRC reestablishment request message, a UE in the RRC connected state may send an RRC reestablishment request message. The RRC reestablishment request message may include at least one of the C-RNTI used in the source PCell, the physical cell identifier (PCI) of the source PCell, the short MAC-I, or the reestablishment cause. The reestablishment cause may include at least one of reconfiguration failure, handover failure, or other failures.

[0260] Based on the transmission of an RRC reestablishment request message, a UE in the RRC connected state (RRC layer) may re-establish the PDCP of SRB1, re-establish the RLC of SRB1, apply the default SRB configuration of SRB1, configure the lower layer (PDCP layer) to suspend the integrity protection and encryption of SRB1, resume SRB1 and submit the RRC reestablishment request message to the lower layer (PDCP layer) for transmission. Based on submitting the RRC reestablishment request message to the lower layer, a UE in the RRC connected state may send the RRC reestablishment request message to the target base station via the cell selected based on the cell selection procedure, where the target base station may or may not be the source base station.

[0261] Based on the expiration of timer T311 or T301, the UE (UE-AS layer) may transition to the RRC idle state and may provide the release cause 'RRC connection failure' to the upper layer (UE-NAS layer) of the UE.

[0262] Based on receiving the release cause "RRC connection failure", when the UE has no outstanding signaling and no outstanding user data, a UE in the RRC idle state (UE-NAS layer) may perform a NAS signaling connection restoration procedure. Based on performing the NAS signaling connection restoration procedure, a UE in the RRC idle state may initiate a registration procedure by sending a registration request message to the AMF.

[0263] Based on receiving the release cause "RRC connection failure", when the UE has outstanding signaling or outstanding user data, a UE (UE-NAS layer) in the RRC idle state can perform a service request procedure by sending a service request message to the AMF.

[0264] Based on receiving an RRC reestablishment request message, the target base station can check whether the UE context of the UE is locally available. Based on the UE context not being locally available, the target base station can perform a UE context retrieval procedure by sending a UE context retrieval request message to the source base station (the last serving base station) of the UE.

[0265] For the RRC connection reestablishment procedure, the UE context retrieval request message can include at least one of a UE context ID, integrity protection parameters, or a new cell identifier. The UE context ID can include at least one of the following: the C-RNTI containing the RRC reestablishment request message; and the PCI of the source PCell (the last serving PCell). The integrity protection parameter for the RRC connection reestablishment procedure can be a short MAC-I. The new cell identifier can be the identifier of the target cell, where the target cell is the cell for which the RRC connection reestablishment has been requested. The new cell identifier is the cell identifier in the system information block (e.g., SIB1) of the target cell (e.g., the selected cell).

[0266] For the RRC connection reestablishment procedure, based on receiving the UE context retrieval request message, the source base station can check the UE context retrieval request message. If the source base station can identify the UE context by means of the UE context ID, and can successfully authenticate the UE by means of the integrity protection included in the UE context retrieval request message, and decides to provide the UE context to the target base station, the source base station can respond to the target base station with a UE context retrieval response message. If the source base station cannot identify the UE context by means of the UE context ID, or if the integrity protection included in the UE context retrieval request message is not valid, the source base station can respond to the target base station with a UE context retrieval failure message.

[0267] For the RRC connection reestablishment procedure, the retrieved UE context response message may include at least one of the Xn Application Protocol (XnAP) ID of the target base station, the XnAP ID of the source base station, the Globally Unique AMF Identifier (GUAMI), or UE context information (e.g., UE context information retrieved UE context response). The UE context information may include at least one of the NG-C UE association signaling reference, UE security capabilities, AS security information, UE aggregated maximum bitrate, PDU session list to be set, RRC context, mobility restriction list, or index to RAT / frequency selection priority. The NG-C UE association signaling reference may be the NG application protocol ID assigned at the AMF of the UE on the NG-C connection with the source base station. The AS security information may include the security key (K gNB ) of the base station and the next-hop link count (NCC) value. The PDU session list to be set may include PDU session resource-related information used at the UE context in the source base station. The PDU session resource-related information may include the PDU session ID, PDU session resource aggregated maximum bitrate, security indication, PDU session type, or QoS flow list to be set. The security indication may include a user plane integrity protection indication and a confidentiality protection indication, which respectively indicate the requirements for user plane (UP) integrity protection and encryption for the corresponding PDU session. The security indication may also include an indication of whether to apply UP integrity protection to the PDU session, an indication of whether to apply UP encryption to the PDU session, and at least one of the maximum integrity protection data rate values (uplink and downlink) for each UE for integrity protection DRB. The PDU session type may indicate at least one of Internet Protocol version 4 (IPv4), IPv6, IPv4v6, Ethernet, or unstructured. The QoS flow list to be set may include at least one of the QoS flow identifier, QoS flow level QoS parameters (QoS parameters to be applied to the QoS flow), or bearer identifier.

[0268] For the RRC connection reestablishment procedure, the retrieved UE context failure message may include at least the XnAP ID of the target base station and a cause value.

[0269] For the RRC connection reestablishment procedure, based on receiving the retrieved UE context response message, the target base station may send an RRC reestablishment message to the UE. The RRC reestablishment message may include at least the network hop link count (NCC) value.

[0270] Based on receiving the RRC reestablishment message, the UE may derive a new security key (K gNB of the base station based on at least one of the current K gNB) Based on the new security key of the base station and the previously configured integrity protection algorithm, the UE can derive the security key (K RRCint ) for RRC signaling integrity protection and the security key (K UPint ) for user plane (UP) data integrity protection. Based on the new security key of the base station and the previously configured encryption algorithm, the UE can derive the security key (K RRCenc ) for encrypting RRC signaling and the security key (K UPenc ) for encrypting user plane (UP) data. Based on K RRCint and the previously configured integrity protection algorithm, the UE can verify the integrity protection of the RRC reestablishment message. Based on the verification failure, the UE (UE-AS layer) can enter the RRC IDLE state and can provide the release cause "RRC connection failure" to the upper layer (UE-NAS layer) of the UE. Based on the verification success, the UE can be configured to resume the integrity protection of SRB1 based on the previously configured integrity protection algorithm and K RRCint , and configured to resume the encryption of SRB1 based on the previously configured encryption algorithm and K RRCenc . The UE can send an RRC reestablishment complete message to the target base station.

[0271] Based on receiving a message indicating failure to retrieve the UE context, the target base station can send an RRC release message to the UE. For example, based on a message indicating failure to retrieve the UE context that includes an RRC release message, the target base station can send an RRC release message to the UE. Based on receiving a message indicating failure to retrieve the UE context, the target base station can send an RRC setup message or an RRC rejection message. Based on receiving a message indicating failure to retrieve the UE context, the target base station can refrain from sending any response message to the UE.

[0272] Figure 17 Fig. shows an example of the RRC connection reestablishment procedure. A UE in the RRC connected state can send and receive data to / from a first base station (e.g., the source base station) via cell 1, where cell 1 is the primary cell (PCell) of the first base station. The UE can detect a failure in the connection with the first base station. Based on this failure, the UE can initiate the RRC reestablishment procedure.

[0273] Based on initiating the RRC connection reestablishment procedure, the UE may start timer T311, suspend all radio bearers except SRB0, and / or reset the MAC (layer). Based on initiating the RRC connection reestablishment procedure, the UE may release the MCG SCell, release the special cell (SpCell) configuration parameters and the multi-radio dual connectivity (MR-DC) related configuration parameters. Based on initiating the RRC connection reestablishment procedure, the UE may perform a cell selection procedure. Based on the cell selection procedure, the UE may select Cell 2 of the second base station (e.g., the target base station), where Cell 2 is a suitable cell. Based on selecting a suitable cell, the UE may stop timer T311 and start timer T301. Based on selecting a suitable cell, if one or more barring timers T309 are running, the UE may stop one or more barring timers T309 for all access categories. Based on stopping one or more barring timers T309, the UE may consider alleviating the barring for all access categories for that cell. Based on selecting a cell, the UE may apply the default L1 parameter values except for the parameters provided in SIB1, apply the default MAC cell group configuration, apply the CCCH configuration, apply the timer alignment timer in SIB1, and initiate the transmission of the RRC reestablishment request message.

[0274] The RRC reestablishment message may include at least one of the C-RNTI used in the source PCell (e.g., Cell 1), the physical cell identifier (PCI) of the source PCell, the short MAC-I, or the reestablishment cause. Based on initiating the transmission of the RRC reestablishment request message, the UE (RRC layer) may re-establish the PDCP of SRB1, re-establish the RLC of SRB1, apply the default SRB configuration of SRB1, configure the lower layer (PDCP layer) to suspend the integrity protection and encryption of SRB1, resume SRB1 and submit the RRC reestablishment request message to the lower layer (PDCP layer) for transmission. Based on initiating the transmission of the RRC reestablishment request message, the UE may send the RRC reestablishment request message to the second base station via Cell 2.

[0275] Upon receiving the RRC Reestablishment Request message, the second base station may check whether the UE context of the UE is locally available. Based on the UE context not being locally available, the second base station may perform a UE context retrieval procedure by sending a UE context retrieval request message to the source base station of the UE. The UE context retrieval request message may include at least one of the following: a UE context ID; an integrity protection parameter; or a new cell identifier. The UE context ID may include at least one of the following: the C-RNTI containing the RRC Reestablishment Request message; and the PCI of the source PCell (the last serving PCell). The integrity protection parameter for the RRC reestablishment procedure may be a short MAC-I. The new cell identifier may be the identifier of the target cell, where the target cell is the cell for which the RRC connection reestablishment has been requested. The new cell identifier is the cell identifier in the system information block (e.g., SIB1) of the target cell (e.g., the selected cell).

[0276] Upon receiving the UE context retrieval request message, the source base station may check the UE context retrieval request message. If the source base station can identify the UE context by means of the C-RNTI, and can successfully authenticate the UE by means of the short MAC-I, and decides to provide the UE context to the second base station, the source base station may respond to the second base station with a UE context retrieval response message. The UE context retrieval response message may include at least one of a GUAMI or UE context information. Upon receiving the UE context retrieval response message, the second base station may send an RRC reestablishment message to the UE. The RRC reestablishment message may include a Network Hop Count (NCC) value.

[0277] Upon receiving the RRC reestablishment message, the UE may derive a new security key (K gNB ) of the base station based on at least one of the current K associated with the NCC value gNB or the Next Hop (NH) parameter. Based on the new security key (K gNB ) of the base station and the previously configured security algorithm, the UE may derive the security keys for the integrity protection and encryption of the RRC signaling (e.g., K RRCint and K RRCenc ) respectively, and the security keys for the integrity protection and encryption of the user plane (UP) data (e.g., K UPint and K UPenc ) respectively. Based on the security key (K RRCint ) for the integrity protection of the RRC signaling, the UE may verify the integrity protection of the RRC reestablishment message. Based on successful verification, the UE may be configured to restore the integrity protection for one or more bearers (e.g., signaling radio bearers or RRC messages) based on the previously configured integrity protection algorithm and K RRCint , and be configured to encrypt based on the previously configured encryption algorithm and K RRCencTo resume encryption of one or more bearers.

[0278] The second base station may send a first RRC reconfiguration message. The RRC first reconfiguration message may include SpCell configuration parameters. Based on the received SpCell configuration parameters, the UE may initiate transmission and reception of data to / from the second base station. The UE may send an RRC reestablishment complete message to the second base station. The RRC reestablishment complete message may include a measurement report. Based on the received measurement report, the second base station may determine to configure an SCell and / or a secondary cell group (e.g., SCG or PSCell). Based on this determination, the second base station may send a second RRC reconfiguration message including SCell configuration parameters and / or MR-DC related configuration parameters. Based on the received second RRC reconfiguration message, the UE may transmit and receive data via the SCell and / or SCG.

[0279] The RRC reconfiguration message may include at least one of cell group configuration parameters of the MCG and / or SCG, radio bearer configuration parameters, or AS security key parameters.

[0280] The UE may remain in CM-CONNECTED and move within the area configured by the base station without notifying the base station when the UE is in the RRC inactive state where the area is the RNA. In the RRC inactive state, the last serving base station may maintain the UE context and the NG connection associated with the UE to the serving AMF and UPF. Based on the downlink data received from the UPF or the downlink UE-associated signaling received from the AMF when the UE is in the RRC inactive state, the last serving base station may perform paging in the cell corresponding to the RNA, and may send RAN paging to the neighboring base station via the Xn interface when the RNA includes the cells of the neighboring base stations.

[0281] The AMF may provide core network assistance information to the base station to assist the base station in deciding whether the UE can be sent to the RRC inactive state. The core network assistance information may include the registered area configured for the UE, the periodic registration update timer, the UE identity index value, UE-specific DRX, an indication of whether the UE is configured with a mobile-initiated connection only (MICO) mode by the AMF; or the expected UE behavior. The base station may use the UE-specific DRX and the UE identity index value to determine the paging occasion for RAN paging. The base station may use the periodic registration update timer to configure a periodic RNA update timer (e.g., timer T380). The base station may use the expected UE behavior to assist in the UE RRC state transition decision.

[0282] The base station can initiate an RRC connection release procedure to transition the UE's RRC state from the RRC connected state to the RRC idle state, from the RRC connected state to the RRC inactive state, from the RRC inactive state to the RRC inactive state when the UE attempts to resume, or from the RRC inactive state to the RRC idle state when the UE attempts to resume. The RRC connection procedure can also be used to release the UE's RRC connection and redirect the UE to another frequency. When the UE's RRC state transitions to the RRC inactive state, the base station can send an RRC release message including suspension configuration parameters. The suspension configuration parameters can include at least one of the following: resume identity, RNA configuration, RAN paging cycle, or network hop link count (NCC) value, where the RNA configuration can include RNA notification area information or a periodic RNA update timer value (e.g., T380 value). When the UE is in the RRC inactive state, the base station can use a resume identity (e.g., inactive RNTI (I-RNTI)) to identify the UE context.

[0283] If the base station has a new and unused {NCC, next hop (NH)} pair, the base station can include the NCC in the suspension configuration parameters. Otherwise, the base station can include the same NCC associated with the current K gNB in the suspension configuration parameters. The NCC is used for AS security. After sending an RRC release message including suspension configuration parameters to the UE, the base station can delete the current AS keys (e.g., K RRCenc , K UPenc ) and K UPint , but can retain the current AS key K RRCint . If the sent NCC value is new and belongs to an unused {NCC, NH} pair, the base station can save the {NCC, NH} pair in the current UE AS security context and can delete the current AS key K gNB . If the sent NCC value is equal to the NCC value associated with the current K gNB , the base station can retain the current AS key K gNB and the NCC. The base station can store the sent resume identity together with the current UE context, which includes the remainder of the AS security context.

[0284] After receiving an RRC release message including suspension configuration parameters from the base station, the UE can verify that the integrity of the received RRC release message including suspension configuration parameters is correct by checking the PDCP MAC-I. If the verification is successful, the UE can obtain the received NCC value and save it as the stored NCC with the current UE context. The UE can delete the current AS keys K RRCenc , K UPenc and KUPint , but keep the current AS key K RRCint key. If the stored NCC value is different from the NCC value associated with the current K gNB , the UE may delete the current AS key K gNB . If the stored NCC is equal to the NCC value associated with the current K gNB , the UE shall keep the current AS key KgNB. The UE may store the received recovery identifier together with the current UE context including the rest of the AS security context for the next state transition.

[0285] Based on receiving an RRC release message including suspension configuration parameters, the UE may reset the MAC, release the default MAC cell group configuration, and re-establish RLC entities for one or more bearers. Based on receiving an RRC release message including suspension configuration parameters, the UE may store the current configuration parameters and the current security keys in the UE inactive AS context. For example, the UE may store some current configuration parameters. The stored current configuration parameters may include the robust header compression (ROHC) state, the QoS flow to DRB mapping rules, the C-RNTI used in the source PCell, the global cell identifier and the physical cell identifier of the source PCell, and all other parameters configured except for the parameters within the synchronized reconfiguration and the serving cell configuration common parameters in the SIB. The stored security keys may include at least one of K gNB and K RRCint . The serving cell configuration common parameters in the SIB may be used to configure the cell-specific parameters of the serving cell of the UE in SIB1. Based on receiving an RRC release message including suspension configuration parameters, the UE may suspend all SRBs and DRBs except SRB0. Based on receiving an RRC release message including suspension configuration parameters, the UE may start timer T380, enter the RRC inactive state, and perform the cell selection procedure.

[0286] A UE in the RRC Inactive state can initiate an RRC connection resume procedure. For example, based on having data or signaling to transmit or receive an RAN paging message, a UE in the RRC Inactive state can initiate an RRC connection resume procedure. Based on initiating the RRC connection resume procedure, the UE can select an access category based on the triggering conditions of the RRC connection resume procedure and perform a unified access control procedure based on the access category. Based on the unified access control procedure, the UE can consider the access attempt of the RRC connection resume procedure as permitted. Based on considering the access attempt as permitted, the UE can apply the default L1 parameter values specified in the corresponding physical layer specification, apply the default SRB1 configuration, apply the CCCH configuration, apply the common timing alignment timer included in SIB1, apply the default MAC cell group configuration, start timer T319 and initiate the transmission of an RRC resume request message.

[0287] Based on initiating the transmission of an RRC resume request message, the UE can set the content of the RRC resume request message. The RRC resume request message can include at least one of a resume identity, a resume MAC-I, or a resume cause. The resume cause can include at least one of emergency, high-priority access, mt access, mo signaling, mo data, mo voice call, mo sms, ran update, mps priority access, mcs priority access.

[0288] Based on initiating the transmission of an RRC resume request message, in addition to the primary cell group configuration parameters, MR-DC related configuration parameters (e.g., secondary cell group configuration parameters) and PDCP configuration parameters, the UE can restore the stored configuration parameters and the stored security keys from the (stored) UE Inactive AS context. The configuration parameters can include at least one of the following: the C-RNTI used in the source PCell, the global cell identity and physical cell identity of the source PCell, and all other parameters configured except for the parameters within the synchronized reconfiguration and serving cell configuration common parameters in the SIB. Based on the current (restored) K associated with the stored NCC value gNB or the next-hop (NH) parameter, the UE can derive a new key (K gNB ) of the base station. Based on the new key of the base station, the UE can derive the security keys for integrity protection and encryption of RRC signaling (e.g., K RRCenc and K RRCint ) respectively, and the security keys for integrity protection and encryption of user plane data (e.g., K UPint and K UPenc ) respectively. Based on the configured algorithm and K RRCint and K UPint, the UE may configure a lower layer (e.g., the PDCP layer) to apply integrity protection to all radio bearers except SRB0. Based on the configured algorithm and K RRCenc and K UPenc , the UE may configure a lower layer (e.g., the PDCP layer) to apply encryption to all radio bearers except SRB0.

[0289] Based on the transmission of the RRC resume request message, the UE may reconstruct PDCP entities for one or more bearers, resume one or more bearers and submit the RRC resume request message to a lower layer, where the lower layer may include at least one of the PDCP layer, the RLC layer, the MAC layer or the physical (PHY) layer.

[0290] The target base station may receive the RRC resume request message. Based on receiving the RRC resume request message, the target base station may check whether the UE context of the UE is locally available. Based on the UE context not being locally available, the target base station may perform a UE context retrieval procedure by sending a UE context retrieval request message to the source base station (the last serving base station) of the UE. The UE context retrieval request message may include at least one of a UE context ID, integrity protection parameters, a new cell identifier or a resume reason, where the resume reason is in the RRC resume request message.

[0291] For the RRC connection resume procedure, based on receiving the UE context retrieval request message, the source base station may check the UE context retrieval request message. If the source base station can identify the UE context by means of the UE context ID, and can successfully authenticate the UE by means of the integrity protection included in the UE context retrieval request message, and decides to provide the UE context to the target base station, the source base station may respond to the target base station with a UE context retrieval response message. If the source base station cannot identify the UE context by means of the UE context ID, or if the integrity protection included in the UE context retrieval request message is not valid, or if the source base station decides not to provide the UE context to the target base station, the source base station may respond to the target base station with a UE context retrieval failure message.

[0292] For the RRC connection resume procedure, the UE context retrieval failure message may include at least the XnAP ID of the target base station, the RRC release message or a cause value.

[0293] For the RRC connection resume procedure, based on receiving the UE context retrieval response message, the target base station may send an RRC resume message to the UE. The RRC resume message may include at least one of radio bearer configuration parameters, cell group configuration parameters of MCG and / or SCG, measurement configuration parameters or an sk counter, where the sk counter is used based on K gNBDerive the security key of the secondary base station.

[0294] Based on receiving a UE context retrieval failure message, the target base station may send an RRC release message to the UE. For example, based on a UE context retrieval failure message including an RRC release message, the target base station may send an RRC release message to the UE. Based on receiving a UE context retrieval failure message, the target base station may send an RRC setup message or an RRC rejection message. Based on receiving a UE context retrieval failure message, the target base station may not send any response message to the UE.

[0295] Based on receiving an RRC resume message, the UE may stop timers T319 and T380. Based on receiving an RRC resume message, the UE may resume master cell group configuration parameters, secondary cell group configuration parameters, and PDCP configuration parameters in the UE inactive AS context. Based on resuming the master cell group configuration parameters and / or secondary cell group configuration parameters, the UE may configure the SCell of the MCG and / or SCG by configuring the lower layer to treat the resumed MCG and / or SCG SCell as being in a deactivated state, discard the UE inactive AS context, and release the suspended configuration parameters.

[0296] Based on the cell group configuration parameters received in the RRC resume message, the UE may perform cell group configuration of the MCG and / or SCG. Based on the radio bearer configuration parameters received in the RRC resume message, the UE may perform radio bearer configuration. Based on the sk counter in the RRC resume message, the UE may perform updating the security key of the secondary base station.

[0297] Figure 18 An example of an RRC connection resume procedure is shown. A UE in the RRC connected state may transmit and receive data to / from a first base station (source base station) via cell 1. The first base station may determine to transition the UE in the RRC connected state to the RRC inactive state. Based on this determination, the base station may send an RRC release message including suspended configuration parameters.

[0298] Based on receiving an RRC release message including suspended configuration parameters, the UE may use the current security key (e.g., K gNB and K RRCintThe security key and the current configuration parameters are stored in the UE inactive AS context. For example, the UE may store some current configuration parameters. The stored (current) configuration parameters may be at least one of the following: Robust Header Compression (ROHC) status; QoS flow to DRB mapping rule; C-RNTI used in the source PCell; global cell identity and physical cell identity of the source PCell; and all other parameters configured except for the parameters within the synchronized reconfiguration in the SIB and the common parameters of the serving cell configuration. The Robust Header Compression (ROHC) status may include the ROHC status of all PDCP entities (or all bearers), where each PDCP entity (or each bearer) of each bearer may have an ROHC status. The QoS flow to DRB mapping rule may be the QoS flow to DRB mapping rule for all data radio bearers (DRBs), where each DRB may have a QoS flow to DRB mapping rule.

[0299] Based on receiving an RRC release message including suspension configuration parameters, the UE may suspend all SRBs and DRBs except SRB0. Based on receiving an RRC release message including suspension configuration parameters, the UE may start timer T380, enter the RRC inactive state, and perform a cell selection procedure. Based on the cell selection procedure, the UE may select cell 2 of the second base station (target base station). The UE in the RRC inactive state may initiate an RRC connection resume procedure. The UE may perform a unified access control procedure. Based on the unified access control procedure, the UE may consider the access attempt of the RRC connection resume procedure as permitted. The UE may apply the default L1 parameter values specified in the corresponding physical layer specification, apply the default SRB1 configuration except for the parameters for which values are provided in SIB1, apply the CCCH configuration, apply the common timing alignment timer included in SIB1, apply the default MAC cell group configuration, start timer T319 and initiate the transmission of an RRC resume request message.

[0300] Based on initiating the transmission of an RRC resume request message, the UE may restore the stored configuration parameters and the stored security key from the (stored) UE inactive AS context. For example, except for the primary cell group configuration parameters, MR-DC related configuration parameters (e.g., secondary cell group configuration parameters), and PDCP configuration parameters, the UE may restore the stored configuration parameters and the stored security key (e.g., K gNB and K RRCint ) from the stored UE inactive AS context. Based on the current (restored) K gNB associated with the stored NCC value or the next-hop (NH) parameter, the UE may derive a new key (K gNB)。Based on the new key at the base station, the UE can derive security keys for integrity protection and encryption of RRC signaling (e.g., K RRCenc and K RRCint ) and security keys for integrity protection and encryption of user plane data (e.g., K UPint and K UPenc ). Based on the configured algorithms and K RRCint and K UPint , the UE (RRC layer) can configure the lower layer (e.g., PDCP layer) to apply integrity protection to all radio bearers except SRB0. Based on the configured algorithms and K RRCenc and K UPenc , the UE can configure the lower layer (e.g., PDCP layer) to apply encryption to all radio bearers except SRB0. For communication between the UE and the base station, integrity protection and / or encryption may be required. Based on integrity protection and / or encryption, the UE may be able to transmit and receive data to / from the second base station. The UE can use the recovered configuration parameters to transmit and receive data to / from the second base station.

[0301] Based on the transmission of the RRC resume request message, the UE can reconstruct the PDCP entity for one or more bearers, resume one or more bearers, and submit the RRC resume request message to the lower layer. Based on the received RRC resume request message, the second base station can check whether the UE context is locally available. Based on the UE context not being locally available, the second base station can perform the UE context retrieval procedure by sending a UE context retrieval request message to the UE's first base station (the last serving base station). The UE context retrieval request message may include at least one of the following: resume identity; resume MAC-I; or resume reason.

[0302] Based on receiving a Retrieve UE Context Request message, the first base station may check the Retrieve UE Context Request message. If the first base station can identify the UE context by means of the UE context ID, and can successfully authenticate the UE by means of the recovered MAC-I, and decides to provide the UE context to the second base station, the first base station may respond to the second base station with a Retrieve UE Context Response message. Based on receiving the Retrieve UE Context Response message, the second base station may send an RRC Resume message to the UE. Based on receiving the RRC Resume message, the UE may resume the master cell group configuration parameters, the secondary cell group configuration parameters, and the PDCP configuration parameters in the UE Inactive AS context. Based on resuming the master cell group configuration parameters and / or the secondary cell group configuration parameters, the UE may configure the SCell of the MCG and / or SCG by configuring the lower layers, consider the resumed MCG and / or SCG SCell as being in a deactivated state, discard the UE Inactive AS context, and release the suspended configuration parameters. The UE may transmit and receive data via the SCell and / or SCG.

[0303] The RRC Resume message may include at least one of the cell group configuration parameters of the MCG and / or SCG, the radio bearer configuration parameters, or the AS security key parameters (e.g., sk counter).

[0304] The base station may send an RRC Release message to the UE to release the RRC connection of the UE. Based on the RRC Release message, the UE may release the established radio bearers and all radio resources.

[0305] The base station may send an RRC Release message to suspend the RRC connection. Based on the RRC Release message, the UE may suspend all radio bearers except the signaling radio bearer 0 (SRB0). The RRC Release message may include suspended configuration parameters. The suspended configuration parameters may include the next-hop link count (NCC) and the resume identifier (e.g., ID or identifier).

[0306] The base station may send an RRC Release message to transition the UE in the RRC connected state to the RRC idle state; or transition the UE in the RRC connected state to the RRC inactive state; or transition the UE in the RRC inactive state back to the RRC inactive state when the UE attempts to resume; or transition the UE in the RRC inactive state to the RRC idle state when the UE attempts to resume.

[0307] The base station may send an RRC Release message to redirect the UE to another frequency.

[0308] The UE can receive an RRC release message from the base station of the serving cell (or the PCell). Based on the RRC release message, the UE can perform UE actions for the RRC release message from the base station. From the moment the RRC release message is received or when the reception of the RRC release message is successfully confirmed, the UE can delay the UE actions for the RRC release message for a period of time (e.g., 60 ms). The UE can send a HARQ acknowledgment to the base station to confirm the RRC release message. Based on the RLC protocol data unit (PDU) including the RRC release message and the RLC PDU including the polling bit, the UE can send an RLC message (e.g., a status report) to the base station to confirm the RRC release message.

[0309] The UE actions for the RRC release message from the base station can include at least one of the following: suspending the RRC connection; releasing the RRC connection; cell (re-)selection procedure; and / or idle / inactive measurement.

[0310] The RRC release message from the base station can include suspension configuration parameters. Based on the suspension configuration parameters, the UE can perform suspending the RRC connection. Suspending the RRC connection can include at least one of the following: media access control (MAC) reset (or reset MAC); releasing the default MAC cell group configuration; reconstructing RLC entities for one or more radio bearers; storing the current configuration parameters and the current security key; suspending one or more bearers, where the bearer includes a signaling radio bearer and a data radio bearer; and / or transitioning to the RRC idle state or the RRC inactive state.

[0311] For example, the suspension configuration parameters can further include RNA configuration parameters. Based on the RNA configuration parameters, the UE can transition to the RRC inactive state. For example, based on the suspension configuration parameters not including the RNA configuration parameters, the UE can transition to the RRC idle state. For example, the RRC release message including the suspension configuration parameters can include an indication to transition to the RRC inactive state. Based on the indication, the UE can transition to the RRC inactive state. For example, based on the RRC release message not including the indication, the UE can transition to the RRC idle state.

[0312] Based on the MAC reset, the UE may perform at least one of the following: Stop all timers running at the UE-MAC layer; Consider all time alignment timers as expired; Set the new data indicator (NDI) of all uplink HARQ processes to the value 0; Stop the ongoing RACH process; Discard the explicitly signaled contention-free random access resources (if any); Flush the Msg 3 buffer; Cancel the triggered scheduling request process; Cancel the triggered buffer status report process; Cancel the triggered power headroom report process; Flush the soft buffers of all DL HARQ processes; For each DL HARQ process, consider the next received transmission of the TB as the first transmission; and / or Release the temporary C-RNTI.

[0313] Based on considering the time alignment timer as expired, the UE may perform at least one of the following: Flush all HARQ buffers of all serving cells; Notify the RRC to release the PUCCH for all serving cells, if configured; Notify the RRC to release the SRS for all serving cells, if configured; Clear any configured downlink assignments and configured uplink authorizations; Clear any PUSCH resources used for semi-persistent CSI reporting; and / or Consider all running time calibration timers as expired.

[0314] The default MAC cell group configuration parameters may include the buffer status report (BSR) configuration parameters (e.g., BSR timer) of the cell group of the base station and the power headroom report (PHR) configuration parameters (e.g., PHR timer or PHR transmission power change factor parameter) of the cell group of the base station.

[0315] Reconstructing the RLC entity may include at least one of the following: Discarding all RLC SDUs, RLC SDU segments, and RLCPDUs, if any; Stopping and resetting the timers of all RLC entities; and Resetting all state variables of the RLC entity to their initial values.

[0316] The RRC release message from the base station may not include the pending configuration parameters. Based on the RRC message not including the pending configuration parameters, the UE may perform releasing the RRC connection. Releasing the RRC connection may include at least one of the following: MAC reset (or reset MAC); Discarding the stored configuration parameters and the stored security keys (or discarding the stored UE inactive AS context); Releasing the suspended configuration parameters; Releasing all radio resources, including releasing the RLC entities, MAC configurations, and the associated PDCP entities and SDAPs for all established radio bearers; and / or Transitioning to the RRC idle state.

[0317] The RRC release message may be an RRC early data completion message.

[0318] Based on the execution of small data transmission, the UE can send or receive a small amount of data without transitioning from the RRC idle state or the RRC inactive state to the RRC connected state. When in the RRC idle state or the RRC inactive state (e.g., without transitioning to the RRC connected state), the execution of small data transmission may include at least one of the following: initiating small data transmission; sending small data; and / or receiving a response message.

[0319] For example, based on small data transmission, a UE in the RRC idle state or the RRC inactive state can execute initiating small data transmission. In response to initiating small data transmission, a UE in the RRC idle state or the RRC inactive state can execute sending small data. In response to sending small data, the UE can receive a response message. For example, the response message may include downlink data (or downlink signaling). For example, based on small data transmission, a UE in the RRC idle state or the RRC inactive state can execute sending small data. In response to sending small data, a UE in the RRC idle state or the RRC inactive state can receive a response message. Sending small data may include at least one of the following: sending at least one of an RRC request message, uplink data (or uplink signaling), or a buffer status report (BSR). For example, sending small data may include sending an RRC request message. For example, sending small data may include sending an RRC request message and uplink data. For example, sending small data may include sending an RRC request message, first uplink data, and a BSR requesting uplink resources for second uplink data. The RRC request message may include at least one of the following: an RRC resume request message; or an RRC early data request message. The response message may include at least one of the following: an RRC response message in response to the RRC request message; downlink data; or an acknowledgement of uplink data (e.g., first uplink data); or uplink resources for uplink data (e.g., second uplink data). The RRC response message of the RRC request message may include at least one of the following: an RRC release message; an RRC early data completion message; an RRC setup message; an RRC resume message; or an RRC reject message.

[0320] Based on receiving an RRC Release message, a UE in the RRC idle state or RRC inactive state can transition to the RRC idle state or RRC inactive state, or remain in the RRC idle state or RRC inactive state. Based on receiving an RRC Early Data Completion message, a UE in the RRC idle state or RRC inactive state can transition to the RRC idle state (or remain in the RRC idle state). Based on receiving an RRC Release message or RRC Early Data Completion message, the UE can consider that the small data transmission is successful. Based on receiving an RRC Setup message or RRC Resume message, a UE in the RRC idle state or RRC inactive state can transition to the RRC connected state. Based on receiving an RRC Setup message or RRC Resume message, the UE can consider that the small data transmission is successful. Based on receiving an RRC Reject message, a UE in the RRC idle state or RRC inactive state can transition to the RRC idle state. Based on receiving an RRC Reject message, the UE can consider that the small data transmission is not successful.

[0321] Figure 19 An example of small data transmission is shown. Based on receiving a first RRC Release message, the UE can transition to the RRC inactive or RRC idle state. A UE in the RRC inactive or idle state can initiate small data transmission. A UE in the RRC inactive or idle state can initiate small data transmission based on having small data to transmit or based on receiving a paging message. For example, the paging message can indicate small data transmission. Based on initiating small data transmission, a UE in the RRC idle state or RRC inactive state can transmit a message of small data transmission to the base station. The message can be Msg 3 or Msg A. The message can include at least one of the following: uplink data and an RRC request message. The wireless device can transmit a message including at least one of the following on the UL-SCH: C-RNTI MAC CE, CCCH SDU, and DTCH. For example, the wireless device can multiplex the CCCH SDU and DTCH in the message. The wireless device can transmit the message to the base station. For example, as part of a random access procedure, the CCCH SDU can be associated with a UE contention resolution identity. For example, a UE in the RRC idle state or RRC inactive state can use configured grant (e.g., pre-configured uplink grant, pre-configured uplink resource (PUR), etc.) to send the CCCH SDU. The CCCH SDU can include at least one of an RRC request message and uplink data (e.g., first uplink data). The DTCH can include uplink data (e.g., first uplink data).

[0322] In Figure 19In the example, based on the message for transmitting small data, a UE in the RRC idle state or the RRC inactive state can receive downlink data in response to the transmission message without transitioning to the RRC connected state. For example, based on initiating small data transmission, a UE in the RRC idle state or the RRC inactive state can transmit a message including at least one of the following: an RRC request message and uplink data. A UE in the RRC idle state or the RRC inactive state can receive at least one of an RRC response message and / or downlink data in response to the RRC request message. The RRC response message can include an RRC release message. The RRC release message can include a second RRC release message, where the RRC release message can include downlink data. Based on the second RRC release message, the UE can transition to the RRC inactive or idle state.

[0323] Small data transmission can include user plane (UP) small data transmission and control plane (CP) small data transmission. Based on UP small data transmission, a UE in the RRC idle state or the RRC inactive state can transmit uplink data via the user plane (e.g., via DTCH). Based on CP small data transmission, a UE in the RRC idle state or the RRC inactive state can send uplink data via the control plane (e.g., CCCH). Based on UP small data transmission, the base station of the UE can receive downlink data from the UPF of the UE via the user plane. Based on CP small data transmission, the base station of the UE can receive downlink data from the AMF of the UE via the control plane. In response to the CCCH SDU and / or DTCH SDU, the base station can send a response message to the UE in the RRC idle state or the RRC inactive state.

[0324] Small data transmission can include at least one of initiating small data transmission, transmitting a message for small data transmission, and receiving a response message to the message. For example, UP small data transmission can include at least one of the following: initiating UP small data transmission; transmitting a message for UP small data transmission (or UP small data via the user plane); and receiving a response message. CP small data transmission can include at least one of the following: initiating CP small data transmission; transmitting a message for CP small data transmission (or CP small data via the control plane); and receiving a response message.

[0325] Initiating small data transmission can include at least one of initiating UP small data transmission and CP small data transmission. Transmitting a message for small data transmission can include at least one of the following: transmitting a message for UP small data transmission; and transmitting a message for CP small data transmission. The response message can be a response message to at least one of the following: the message, the RRC request message, and / or (first) uplink data.

[0326] For UP small data transmission, the DTCH SDU may include uplink data (for small data transmission). For example, for UP small data transmission, the UE may send a DTCH SDU multiplexed with a CCCH SDU. For example, for UP small data transmission, the CCCH SDU may include an RRC request message. For example, for UP small data transmission, the RRC request message may be an RRC resume request message.

[0327] For CP small data transmission, the UE may send a CCCH SDU including uplink data. For example, for CP small data transmission, the RRC request message may include uplink data. For example, for CP small data transmission, the RRC request message may be an RRC early data request message.

[0328] Small data transmission may include at least one of early data transmission (EDT) and preconfigured uplink resource (PUR) transmission (or (small data) transmission using PUR). EDT may include a random access procedure, while PUR may not include a random access procedure. For small data transmission, a UE in the RRC idle state or RRC inactive state may require uplink resources (authorization) to send a message for small data transmission (e.g., uplink data). The uplink resources may include dynamic uplink resources from the base station or preconfigured uplink resources. For EDT, the UE may receive uplink resources (e.g., dynamic uplink resources) in response to a random access preamble. For example, the random access preamble may be configured for EDT. The random access preamble may be a dedicated random access preamble for EDT. The random access preamble may request uplink resources for EDT.

[0329] UP small data transmission may include UP EDT and UP PUR (or UP (small data) transmission using PUR). CP small data transmission may include CP EDT and CP PUR (or CP (small data) transmission using PUR). Small data transmission using PUR may include at least one of the following: UP small data transmission using PUR; and CP small data transmission using PUR.

[0330] A UE in the RRC inactive state or RRC idle state may determine to initiate small data transmission based on the condition for small data transmission being met. The condition may include at least one of the following: EDT condition; and PUR condition. The EDT condition may include at least one of the following: UP EDT condition and CP EDT condition.

[0331] A UE in the RRC Inactive state or the RRC Idle state may determine to initiate small data transmission of UP EDT based on the satisfaction of the UP EDT condition. The UP EDT condition may include at least one of the following: a common EDT condition; and a UP EDT specific condition. The UP EDT specific condition may include at least one of the following: the UE supports UP EDT; the system information of the serving cell indicates UP EDT support; and the UE has a stored NCC value provided in the RRC release message including suspension configuration parameters during a previous suspension procedure.

[0332] The common EDT condition may include at least one of the following: for a mobile originated call, the size of the resulting MAC PDU including the total uplink data is expected to be less than or equal to the maximum transport block size (TBS) of Msg 3 applicable to the UE performing EDT; and / or the establishment or resume request is for a mobile originated call, and the establishment cause is mo data or mo abnormal data or delay tolerant access.

[0333] A UE in the RRC Inactive state or the RRC Idle state may determine to initiate small data transmission of CP EDT based on the satisfaction of the CP EDT condition. The CP EDT condition may include a common EDT condition and a CP EDT specific condition. The CP EDT specific condition may include at least one of the following: the UE supports CP EDT; and the system information of the serving cell indicates CP EDT support.

[0334] Figure 20 An example of EDT is shown. Based on receiving a first RRC release message from the base station, the UE may transition to the RRC Inactive or RRC Idle state. The UE may have first uplink data in the uplink buffer. A UE in the RRC Idle state or the RRC Inactive state may determine to initiate small data transmission based on at least one of the following: the UP EDT condition, or the CP EDT condition is satisfied. In response to initiating small data transmission, the UE may perform an EDT RACH procedure. Based on the EDT RACH procedure, the UE may select a random access preamble configured for EDT and send the random access preamble to the base station. In response to the random access preamble configured for EDT, the UE may receive uplink resources / grant for EDT. Based on the uplink resources / grant for EDT, the UE may send a message for small data transmission. For example, the message may include at least one of the following: an RRC request message; and / or the first uplink data using the uplink resources of EDT.

[0335] In Figure 20In an example, a UE in the RRC idle state or RRC inactive state can receive a response message in response to at least one of the following: the message; an RRC request message; and / or first uplink data. The response message can include an RRC release message. The RRC release message can include downlink data. Based on receiving the response message, the UE in the RRC idle state or RRC inactive state can consider the small data transmission to be successful. Based on this consideration, the UE in the RRC idle state or RRC inactive state can empty at least one of the uplink buffers of the first uplink data. For example, in response to Msg 3 (or Msg A) including at least one of the RRC request message and / or the first uplink data, the UE in the RRC idle state or RRC inactive state can receive Msg 4 (or Msg B). Msg 4 can include an RRC release message.

[0336] In Figure 20 In an example, based on receiving Msg 4, the UE in the RRC idle state or RRC inactive state can consider the small data transmission to be successful. Based on this consideration, the UE in the RRC idle state or RRC inactive state can empty at least one of the uplink buffer of the first uplink data and / or the uplink buffer of the RRC request message. For example, based on this consideration, the UE in the RRC idle state or RRC inactive state can flush at least one of the HARQ buffers of the first uplink data and / or the HARQ buffer of the RRC request message. Based on the RRC release message not including a suspension configuration parameter, the UE in the RRC idle state or RRC inactive state can perform an RRC connection release. For example, based on the RRC connection release, the UE in the RRC idle state or RRC inactive state can transition to the RRC idle state. Based on the RRC release message including a suspension configuration parameter, the UE in the RRC idle state or RRC inactive state can use the suspension configuration parameter to perform an RRC connection suspension. For example, based on using the suspension configuration parameter to suspend the RRC connection, the UE can transition the RRC state of the UE from the RRC inactive state back to the RRC inactive state, or from the RRC idle state back to the RRC idle state.

[0337] A UE in the RRC connected state can communicate with a first base station based on a first configuration parameter and a first security key. The first base station can send an RRC release message to the UE. Based on receiving the RRC release message including the first suspension configuration parameter, the UE can execute suspending the RRC connection based on the first suspension configuration parameter. The UE can transition to the RRC idle state or the RRC inactive state. Based on the RRC release message, the UE can execute a cell (re)-selection procedure. Based on the cell (re)-selection procedure, a UE in the RRC idle state or the RRC inactive state can select a cell 2 of a second base station (target base station). A UE in the RRC idle state or the RRC inactive state can determine to initiate UP small data transmission based on the UP EDT condition being satisfied. Based on initiating the UP small data transmission, a UE in the RRC idle state or the RRC inactive state can use the first suspension configuration parameter to execute initiating the UP small data transmission. In response to initiating the UP small data transmission, a UE in the RRC idle state or the RRC inactive state can execute an EDT RACH procedure. Based on the EDT RACH procedure, the UE can select a random access preamble configured for EDT and transmit the random access preamble to the second base station via cell 2. In response to the random access preamble configured for EDT, a UE in the RRC idle state or the RRC inactive state can receive the (dynamic) uplink resource for EDT. Based on the uplink resource for EDT, a UE in the RRC idle state or the RRC inactive state can use the first suspension configuration parameter to execute sending the UP small data. For example, a UE in the RRC idle state or the RRC inactive state can use the uplink resource for EDT to send uplink data.

[0338] For PUR transmission, the UE can send a PUR configuration request message to the base station in the RRC connected state, where the PUR configuration request message can include at least one of the following: the requested number of PUR occasions, where the number can be one or infinite; the requested period of PUR; the transport block size (TBS) of the requested PUR; and / or the time offset of the requested first PUR occasion.

[0339] Based on the PUR configuration request message, the base station can send PUR configuration parameters including preconfigured uplink resources to the UE. For example, in response to the PUR configuration request message, the base station can send PUR configuration parameters including preconfigured uplink resources to the UE. For example, the base station can send an RRC release message including the PUR configuration parameters.

[0340] The PUR configuration parameters may include at least one of the following: an indication to establish or release the PUR configuration parameters; the number of PUR occasions; the PUR resource identifier (RNTI PUR); the time offset value of the first PUR occasion (PUR start time); the periodicity of the PUR resource (PUR periodicity); the duration of the PUR response window (PUR response window time); the threshold of the serving cell RSRP change in dB for TA verification (PUR change threshold), where the threshold includes the RSRP increase threshold and the RSRP decrease threshold; the value of the time alignment timer for PUR; and / or the physical configuration parameters of PUR. The physical configuration parameters of PUR may include at least one of the following: the PUSCH configuration parameters of PUR; the PDCCH configuration parameters of PUR; the PUCCH configuration parameters of PUR; the downlink carrier configuration parameters for PUR; and / or the uplink carrier frequency of the uplink carrier for PUR.

[0341] The UE may determine to initiate a small data transmission using PUR (or a (small data) transmission using PUR) based on the PUR condition being satisfied. The PUR condition may include at least one of the following: the UE has valid PUR configuration parameters; the UE has a valid timing alignment (TA) value; and / or the establishment or resume request is for a mobile originated call and the establishment cause is mo data or mo abnormal data or delay tolerant access.

[0342] The PUR condition may further include at least one of the following: the UE supports PUR; the system information of the serving cell indicates PUR support; and / or the UE has a stored NCC value provided in an RRC release message including suspension configuration parameters during a previous suspension procedure.

[0343] The UE may determine that the timing alignment value of the small data transmission using PUR is valid based on the TA verification condition of PUR being satisfied. The TA confirmation condition of PUR may include at least one of the following: the time alignment timer for PUR is running; or the serving cell RSRP has not increased by more than the RSRP increase threshold and has not decreased by more than the RSRP decrease threshold.

[0344] In response to receiving the PUR configuration parameter, the UE may store or replace the PUR configuration parameter provided by the PUR configuration parameter based on an indication requesting the establishment of the PUR configuration parameter. In response to receiving the PUR configuration parameter, the UE may start the time alignment timer for PUR with the value of the time alignment timer for PUR and configure the PUR configuration parameter. For example, based on an indication requesting the establishment of the PUR configuration parameter, the UE may start the time alignment timer for PUR with the value of the time alignment timer for PUR and configure the PUR configuration parameter. In response to receiving the PUR configuration parameter, the UE may discard the PUR configuration parameter based on an indication requesting the release of the PUR configuration parameter. In response to configuring the PUR configuration parameter, the UE may generate preconfigured uplink resources / authorizations for PUR based on the PUR configuration parameter. For example, based on the PUR configuration parameter, the UE may determine when to generate the preconfigured uplink resources / authorizations. For example, based on the PUR start time and the PUR period, the UE may determine when to generate the preconfigured uplink resources / authorizations. For example, based on the PUSCH configuration parameter, the UE may determine the preconfigured uplink resources / authorizations (transmission block). For example, based on the PUSCH configuration parameter, the UE may determine the preconfigured uplink resources / authorizations (transmission block).

[0345] Figure 21An example of PUR is shown. Based on receiving the first RRC release message, the UE can transition to the RRC idle state or the RRC inactive state. The UE can receive the PUR configuration parameters via the previous RRC release message. The previous RRC release message can be the first RRC release message. In response to receiving the PUR configuration parameters, the UE in the RRC idle state or the RRC inactive state can start the time alignment timer of PUR with the value of the time alignment timer of PUR and configure the PUR configuration parameters. In response to configuring the PUR configuration parameters, the UE in the RRC idle state or the RRC inactive state can generate the preconfigured uplink resources / grant of PUR based on the PUR configuration parameters. Based on the first RRC release message, the UE can perform the cell (re)selection procedure. Based on the cell (re)selection procedure, the UE in the RRC idle state or the RRC inactive state can select the cell 2 of the second base station (target base station). The UE in the RRC idle state or the RRC inactive state can have the first uplink data in the uplink buffer or receive a paging message. The UE in the RRC idle state or the RRC inactive state can determine to initiate the small data transmission of PUR based on the PUR condition being met. For example, in response to having the first uplink data or receiving a paging message, the UE in the RRC idle state or the RRC inactive state can determine to initiate the small data transmission based on the PUR condition being met. Based on this initiation, the UE can transmit the message of the small data transmission. The UE can use PUR (or the uplink resources / grant of PUR) to transmit the message and the UE can perform the small data transmission. The message can include at least one of the following: an RRC request message; and / or the first uplink data. For example, the message can be Msg 3 (or Msg A) including at least one of CCCH SDU and / or DTCH SDU, where CCCH SDU includes the RRC request message and DTCH SDU includes the first uplink data.

[0346] In Figure 21In an example, in response to transmitting a message using a PUR (or an uplink resource / grant of the PUR), a UE (UE-MAC entity) may start a PUR response window timer with a PUR response window time. Based on this start, the UE may monitor the PDCCH identified by the PUR RNTI until the PUR response window timer expires. The UE (UE-MAC entity) may receive a downlink message (e.g., DCI) identified by the PUR RNTI on the PDCCH. Based on receiving the downlink message indicating an uplink grant for retransmission, the UE may restart the PUR response window timer at the last subframe, pulse time gap (e.g., 4 subframes) of the PUSCH transmission indicating the uplink grant. Based on this restart, a UE in the RRC idle state or RRC inactive state may monitor the PDCCH identified by the PUR RNTI until the PUR response window timer expires. Based on receiving the downlink message indicating an L1 (layer 1) ack of the PUR, a UE in the RRC idle state or RRC inactive state may stop the PUR response window timer and consider the small data transmission using the PUR to be successful. Based on receiving the downlink message indicating a fallback of the PUR, a UE in the RRC idle state or RRC inactive state may stop the PUR response window timer and consider the small data transmission using the PUR to have failed. Based on receiving the downlink message indicating a PDCCH transmission (downlink grant or downlink assignment) addressed to the PUR RNTI and / or MAC PDU including successfully decoded uplink data, a UE in the RRC idle state or RRC inactive state may stop the PUR response window timer and consider the small data transmission using the PUR to be successful. Based on the PDCCH transmission, a UE in the RRC idle state or RRC inactive state may receive at least one of an RRC response message and downlink data, where the RRC response message is at least one of an RRC release message or an RRC early data completion message. Based on not receiving any downlink message until the PUR response window timer expires, a UE in the RRC idle state or RRC inactive state may consider the small data transmission using the PUR to have failed. Based on considering that the small data transmission using the PUR has failed, the UE may perform a random access procedure. For example, the random access procedure may include an EDT RACH procedure.

[0347] In the example, a UE in the RRC connected state can communicate with a first base station based on a first configuration parameter and a first security key. The first base station can send an RRC release message to the UE. Based on receiving the RRC release message including a first suspension configuration parameter, the UE can execute a suspended RRC connection based on the first suspension configuration parameter. The UE can transition to the RRC idle state or the RRC inactive state. The UE can receive a PUR configuration parameter via a previous RRC release message. The previous RRC release message can be the RRC release message. In response to receiving the PUR configuration parameter, the UE in the RRC idle state or the RRC inactive state can start a time alignment timer for PUR with the value of the time alignment timer for PUR and configure the PUR configuration parameter. In response to configuring the PUR configuration parameter, the UE in the RRC idle state or the RRC inactive state can generate preconfigured uplink resources / authorizations for PUR based on the PUR configuration parameter. Based on the RRC release message, the UE in the RRC idle state or the RRC inactive state can execute a cell (re)selection procedure. Based on the cell (re)selection procedure, the UE in the RRC idle state or the RRC inactive state can select a cell 2 of a second base station (target base station). The UE in the RRC idle state or the RRC inactive state can determine to initiate small data transmission using PUR based on the PUR condition being met. For example, the UE in the RRC idle state or the RRC inactive state can initiate small data transmission using the first suspension configuration parameter. Based on the (preconfigured) uplink resources for PUR, the UE in the RRC idle state or the RRC inactive state can use the first suspension configuration parameter to transmit a message for small data transmission.

[0348] In an example, a UE in the RRC idle state or the RRC inactive state can perform at least one of the following: transmit one or more uplink data to a base station; and receive one or more uplink data from the base station. For example, a UE in the RRC idle state or the RRC inactive state can determine to initiate small data transmission. Based on this initiation, the UE in the RRC idle state or the RRC inactive state can transmit a message for small data transmission to the base station. The message can include at least one of the following: an RRC request message for small data transmission; uplink data; and auxiliary parameters indicating small data transmission. The auxiliary parameters can indicate the service information of the small data transmission. For example, the auxiliary parameters can indicate that subsequent data of the uplink data is expected. The auxiliary parameters can indicate subsequent uplink data in the uplink buffer of the wireless device. The base station can send an uplink grant for the subsequent data. The UE can transmit or receive the subsequent data without transitioning to the RRC connected state (e.g., when in the RRC idle state or the RRC inactive state). For example, based on the message, the base station can determine to allow transmission / reception without transitioning to the RRC connected state (e.g., when in the RRC idle state or the RRC inactive state). Based on this determination, the base station can send an uplink grant for the subsequent data.

[0349] In an example, a base station distributed unit can determine to request the base station central unit to release the context of a wireless device (UE) (or the logical F1 connection associated with the UE). Based on this determination, the base station distributed unit can transmit a context release request message to the base station central unit.

[0350] In an example, the base station central unit can determine to release the context of a wireless device (UE) (or the logical F1 connection associated with the UE). Based on this determination, the base station distributed unit can transmit a context release request message to the base station central unit. The base station central unit can determine to release the context of the wireless device (UE) based on the context release request message from the base station distributed unit. In response to the context release request message, the base station central unit can transmit a context release command to the base station distributed unit.

[0351] In an example, small data transfer (SDT) may include exchanging user data between a wireless device and a base station while the wireless device remains in a non-connected state (e.g., idle, inactive, etc.). The amount of data exchanged in SDT may be less than a threshold data amount. SDT may include an SDT and / or an SDT transmission sequence of a small amount of data. For example, using SDT, the wireless device and / or the base station may use a control plane (e.g., control signals, RRC messages, etc.) to transmit and / or receive user data. For example, using SDT, when the wireless device remains in a non-connected state (e.g., idle, inactive, etc.), the wireless device and / or the base station may use a user plane to transmit and / or receive user data. For example, using SDT, the wireless device may transmit and / or receive user data without completing a connection setup or restoration procedure (accompanied by control plane signaling).

[0352] SDT may include any procedure for small data exchange where the small data exchange is performed without transitioning the wireless device to a connected state. SDT may include a configured grant-based transmission of small data and / or a random access-based transmission of small data. For example, SDT may include a transmission using preconfigured uplink resources (PUR) and / or early data transmission (EDT). For example, in a configured (preconfigured) grant-based transmission (e.g., a transmission using PUR), the wireless device may be configured with a preconfigured grant, and the grant may be used to send small data without transitioning to a connected state. For example, in a random access-based transmission (e.g., EDT), the wireless device may obtain an uplink grant via a broadcast message (e.g., system information), dedicated signaling (e.g., signaling specific to the wireless device), and / or via a random access procedure (e.g., based on preamble transmission), and transmit and / or receive small data based on the uplink grant without transitioning to a connected state.

[0353] Figure 22An example of information for updating a logical channel for small data transmission is shown. A wireless device may store information of a logical channel configured for small data transmission in the RRC Inactive state (or RRC Idle state). The information may be information of logical channel A (e.g., logical channel information A). For example, when the wireless device is in the RRC Connected state, the wireless device may receive information from the base station. The wireless device may transition from the RRC Connected state to the RRC Inactive state (or RRC Idle state). The wireless device in the RRC Inactive state (or RRC Idle state) may access the base station via a cell of the base station. The wireless device may indicate to the base station that the wireless device does not intend to transition to the RRC Connected state. For example, the wireless device may indicate not intending to transition to the RRC Connected state based on a transmission of an RRC request message indicating an RAN-based notification area update (RNA update). For example, the wireless device may indicate not intending to transition to the RRC Connected state based on a transmission of a message for small data transmission, where the message includes at least one of the following: an RRC request message; (small) data; and auxiliary parameters indicating small data transmission.

[0354] In Figure 22 the example of, a wireless device in the RRC Inactive state or RRC Idle state may indicate to the base station that the wireless device does not intend to transition to the RRC Connected state. The base station may intend to update information of a logical channel configured for small data transmission. The base station may transition the wireless to the RRC Connected state. For example, based on the transition to the RRC Connected state, the base station may transmit updated information (e.g., information of logical channel B or logical channel information B) to the wireless device. Based on receiving the updated information, the wireless device in the RRC Connected state may store the updated information. The base station may transition the wireless device to the RRC Inactive state. For example, the base station may transition the wireless device to the RRC Inactive state based on transmitting an RRC release message. The wireless device may transition from the RRC Connected state to the RRC Inactive state.

[0355] In Figure 22 the example of, a wireless device in the RRC Inactive state that does not intend to transition to the RRC Connected state may transition to the RRC Connected state to update information of a logical channel configured for small data transmission. The wireless device in the RRC Connected state may transition back to the RRC Inactive state. The transition from the RRC Inactive state to the RRC Connected state and the transition from the RRC Connected state to the RRC Inactive state may result in signal overhead and power consumption of the transitioning wireless device due to the transition of the RRC Connected state and time.

[0356] In the present disclosure, the terms configured grant (CG), configured uplink grant (CUG), and preconfigured uplink resource (PUR) may be used interchangeably.

[0357] In the present disclosure, transmissions of a wireless device in RRC Inactive state and / or RRC Idle state (i.e., transmissions of a wireless device not in RRC Connected state) may be associated with Small Data Transmissions (SDT) and / or SDT procedures.

[0358] In the prior art, a base station may transmit information on logical channels and / or radio bearers in RRC Connected state (e.g., logical channel configuration) to a wireless device. When the wireless device is in RRC Connected state, the base station may send the logical channel configuration via an RRC Reconfiguration message. When the wireless device is in RRC Connected state, the wireless device may use the logical channel configuration to communicate with the base station. When the wireless device is in RRC Connected state, the base station may configure the logical channel for small data transmission. When the wireless device is in RRC Inactive and / or RRC Idle state (e.g., after transitioning from RRC Connected state to Inactive and / or Idle), the logical channel configuration may be used. Based on the logical channel configuration of the logical channel, when the wireless device is in RRC Inactive state, the wireless device may perform small data transmission (SDT) (e.g., SDT procedures).

[0359] In some scenarios, when the wireless device is in RRC Inactive and / or RRC Idle state (e.g., after the wireless device has transitioned from RRC Connected state), the base station may determine to configure the logical channel configuration of a logical channel to the wireless device. For example, the base station may determine that a previous configuration of one or more logical channels of a small data transmission procedure is to be updated. For example, the base station may determine to reconfigure the wireless device for small data transmission based on a new and / or different logical channel configuration. For example, the base station may need to update one of the parameters in the logical channel configuration. In the prior art, when the wireless device is in RRC Connected state (e.g., in an RRC Reconfiguration message), the logical channel configuration is transmitted to the wireless device. If the wireless device is not in RRC Connected state, for the purpose of the logical channel configuration of the logical channel for small data transmission, the base station may, for example, transition the wireless device to RRC Connected state. Transitioning to RRC Connected state to configure the logical channel configuration may result in increased signaling overhead, power consumption, and latency of small data transmission.

[0360] Exemplary embodiments of the present disclosure relate to an enhanced procedure for configuring a logical channel configuration of a logical channel configured for transmission (e.g., small data transmission) in RRC Inactive state or RRC Idle state. Although the prior art continues to implement high-overhead procedures for configuring logical channel configurations, the exemplary embodiments avoid transitioning the wireless device to RRC Connected state when the base station configures the logical channel configuration of a logical channel configured for transmission (e.g., small data transmission) in RRC Inactive state or RRC Idle state.

[0361] In an exemplary embodiment of the present disclosure, the exemplary embodiment utilizes an RRC release procedure / message to more effectively configure the logical channel configuration of a logical channel configured for small data transmission. For example, a base station may transmit, via an RRC release message, the logical channel configuration of a logical channel configured for small data transmission to a wireless device. For example, the base station may transmit the logical channel configuration of a logical channel configured for small data transmission to the wireless device without transitioning the wireless device to the RRC connected state. The wireless device that receives the RRC release message may remain in the RRC inactive state or the RRC idle state. The exemplary embodiment may reduce the unnecessary signaling overhead caused by RRC signaling and / or unnecessary transitions to the RRC connected state to reconfigure the logical channel configuration of a logical channel configured for small data transmission.

[0362] In an exemplary embodiment of the present disclosure, the exemplary embodiment utilizes an RRC reconfiguration procedure / message to more effectively configure the logical channel configuration of a logical channel configured for small data transmission. For example, a base station may transmit a first logical channel configuration of a first logical channel configured for transmission in the RRC connected state (e.g., via an RRC reconfiguration message) to a wireless device. Based on the first logical channel configuration, when the wireless device is in the RRC connected state, the wireless device may be able to transmit data of the first logical channel to the base station. The base station may transmit a second logical channel configuration of a second logical channel via an RRC reconfiguration message, the second logical channel configuration being configured for transmission in the RRC inactive state or the RRC idle state (e.g., small data transmission). The wireless device may not apply / configure the second logical channel configuration until it receives an RRC release message; or transitions to the RRC inactive state or the RRC idle state; or determines to transmit in the RRC inactive state or the RRC idle state. Based on the second logical channel configuration, the wireless device may transmit data of the second logical channel to the base station. The exemplary embodiment may reduce the unnecessary signaling overhead caused by unnecessary transitions to the RRC connected state to reconfigure the logical channel configuration of a logical channel configured for small data transmission.

[0363] In an exemplary embodiment of the present disclosure, one or more logical channel configurations may include at least one of the following: one or more first permitted parameters for a first transmission in the RRC inactive state or the RRC idle state; and one or more second permitted parameters for a second transmission in the RRC connected state. One or more first permitted parameters may be associated with a first logical channel configured for transmission in the RRC inactive state or the RRC idle state. One or more second permitted parameters may be associated with a second logical channel configured for a second transmission in the RRC connected state. For example, the first logical channel configuration of one or more logical channel configurations may include one or more first permitted parameters. The second logical channel configuration of one or more logical channel configurations may include one or more second permitted parameters. The first logical channel configuration may be the logical channel configuration of the first logical channel. The second logical channel configuration may be the logical channel configuration of the second logical channel. The first logical channel configuration may be the second logical channel configuration. The exemplary embodiment may reduce unnecessary signaling overhead caused by an unnecessary transition to the RRC connected state to reconfigure the logical channel configuration of a logical channel configured for small data transmission.

[0364] In an exemplary embodiment of the present disclosure, one or more first permitted parameters may include a first permitted configured grant (CG) list. The first permitted CG list may indicate one or more first CGs (or one or more first CG configurations) permitted for the transmission of data for the first logical channel. One or more first CGs (or one or more first CG configurations) may be configured for the first transmission in the RRC inactive state or the RRC idle state. One or more first permitted parameters may include a first permitted configured grant (CG) list. The second permitted CG list may indicate one or more second CGs (or one or more second CG configurations) permitted for the transmission of data for the second logical channel. One or more second CGs (or one or more second CG configurations) may be configured for the second transmission in the RRC connected state. The exemplary embodiment may reduce unnecessary signaling overhead caused by an unnecessary transition to the RRC connected state to reconfigure the logical channel configuration of a logical channel configured for small data transmission.

[0365] In an example, when the wireless device is in the RRC inactive state or the RRC idle state, the wireless device may receive information on a first logical channel configured for small data transmission from the base station. When the wireless device is in the RRC inactive state or the RRC idle state, the base station may transmit information to the wireless device.

[0366] In an example, when the wireless device is in the RRC inactive state or the RRC idle state, the wireless device may receive information on a first logical channel configured for small data transmission from the base station via at least one of the following: a physical layer message (e.g., DCI); or a MAC message (e.g., MAC CE); or an RRC message (e.g., an RRC release message).

[0367] In an example, the wireless device may receive a radio resource control (RRC) release message from the base station indicating a transition to the RRC inactive state. The RRC release message may include information on a first logical channel configured for small data transmission.

[0368] In an example, the information on the first logical channel configured for small data transmission may include at least one of the following: a logical channel identifier of the first logical channel; and an indication allowing the first logical channel to use small data transmission. Based on this information, the wireless device in the RRC inactive state or the RRC idle state may transmit data of the first logical channel to the base station and / or receive data of the first logical channel from the base station. For example, based on this information, the wireless device in the RRC inactive state or the RRC idle state may determine to initiate small data transmission to transmit or receive data of the first logical channel. Based on this information, the wireless device in the RRC inactive state or the RRC idle state may transmit data of the first logical channel to the base station / receive data of the first logical channel from the base station.

[0369] In an example, the base station may configure a (pre)-configured grant for small data transmission (e.g., PUR) to the wireless device. The first logical channel configured for small data transmission configuration may be associated with the (pre)-configured grant for small data transmission. The information on the first logical channel configured for small data transmission may further indicate the configured grant associated with the first logical channel. This information may include a list of allowed configured grants (or a list of allowed PURs). The list of allowed configured grants may indicate that data of a second logical channel is mapped to a first configured grant configuration of the list of allowed configured grants. For example, the list of allowed configured grants may indicate that data of a second logical channel cannot be mapped to one or more configured grant configurations of the list of allowed configured grants. The list of allowed configured grants may indicate that data of a second logical channel is mapped to one or more configured grant configurations of the list of allowed configured grants. The first logical channel may include a second logical channel. One or more configured grant configurations may be all configured grant configurations or any configured grant configuration.

[0370] For example, based on an allowed configured grant list, a wireless device can determine whether to use a (pre)-configured grant for small data transmission to transmit data of a logical channel. For example, the allowed configured grant list can indicate that data of a second logical channel is mapped to a first configured grant configuration of the allowed configured grant list. Based on the logical channel of the data being the second logical channel, a wireless device in the RRC inactive state or the RRC idle state can determine to use the configured grant configured with a first logical channel to transmit data of the logical channel. For example, based on the logical channel of the data being the second logical channel, a wireless device in the RRC inactive state or the RRC idle state can determine to use a PUR (or a configured grant) to initiate small data transmission. A wireless device in the RRC inactive state or the RRC idle state can use the configured grant configured with a first logical channel to transmit data of the logical channel.

[0371] In an example, the first logical channel can include the second logical channel. For example, the first logical channel can include logical channel A and logical channel B. The second logical channel can be logical channel B. Logical channel B can be mapped to a first configured grant configuration of the allowed configured grant list.

[0372] In an example, the allowed configured grant list can include a configured grant configuration index of a first configured grant configuration. The first configured grant configuration can include at least one of the following: a second configured grant configuration stored in the wireless device; and a third configured grant configuration in an RRC release message. For example, a wireless device in the RRC inactive state or the RRC idle state can store the second configured grant configuration with configuration index #2. The allowed configured grant list can include the configuration index #2 of the second configured grant configuration. The allowed configured grant list can include the configuration index #3 of the third configured grant configuration not stored in the wireless device.

[0373] In an example, the base station can indicate to release the second configured grant configuration. For example, the base station can indicate a configured grant configuration index and release the configured grant configuration of the configured grant configuration index. The base station can indicate information about the logical channel associated with the configured grant configuration. For example, the base station can further indicate that data of the logical channel cannot be mapped to the configured grant configuration of the configured grant configuration index. The base station can indicate the logical channel identifier and the configured grant configuration index of the logical channel. The indication can include indication via at least one of the following: an RRC release message; information; or the allowed configured grant list.

[0374] In an example, the base station may indicate to modify / update the second configured grant configuration. For example, the base station may indicate a configured grant configuration index and modify / update the configured grant configuration corresponding to the configured grant configuration index. The base station may send the parameters of the configured grant configuration to be modified / updated. The base station may indicate information on the logical channel associated with the configured grant configuration. For example, the base station may further indicate that the data of the logical channel cannot be mapped to the configured grant configuration corresponding to the configured grant configuration index. The base station may indicate the logical channel identifier of the logical channel and the configured grant configuration index. The indication may include indication via at least one of the following: an RRC release message; information; or a permitted configured grant list. The indication and transmission parameters may include indicating and transmitting the parameters via a single message.

[0375] In an example, the base station may indicate to set a third configured grant configuration. For example, the base station may transmit the configured grant configuration to be set (e.g., the third configured grant configuration) and indicate to set the configured grant configuration. The base station may indicate information on the logical channel associated with the configured grant configuration. For example, the base station may further indicate that the data of the logical channel can be mapped to the configured grant configuration corresponding to the configured grant configuration index. The base station may indicate the logical channel identifier of the logical channel and the configured grant configuration index. The indication may include indication via at least one of the following: an RRC release message; information; or a permitted configured grant list. The indication and transmission parameters may include indicating and transmitting the parameters via a single message.

[0376] In an example, the third configured grant configuration may include PUR configuration parameters. For example, the third configured grant configuration may further include at least one of the following: the configured grant configuration index of the third configured grant configuration; the configured grant of the third authorization configuration; the bandwidth part of the third configured grant configuration; the serving cell of the third configured grant configuration; and the synchronization signal block (SSB) of the third configured grant configuration. For example, based on the third configured configuration, the wireless device may transmit a message via the bandwidth part using the configured grant. For example, based on the third configured configuration, the wireless device may transmit a message via the serving cell using the configured grant. For example, based on the third configured configuration, the wireless device may transmit a message via the SSB using the configured grant. The message may include at least one of the following: an RRC request message for small data transmission; and the data of the first logical channel.

[0377] In an example, the fourth configured grant configuration for small data transmission may include a permitted logical channel list, which indicates that the data of the third logical channel in the permitted logical channel list is mapped to the fourth configured grant configuration. The RRC release message may include the fourth configured grant configuration for small data transmission. The information may include the fourth configured grant configuration for small data transmission.

[0378] In an example, the information may further include at least one of the following: a list of allowed serving cells, which indicates that data of the first logical channel is mapped to zero or more cells in the list of allowed serving cells; a list of allowed subcarrier spacings (SCSs), which indicates that data of the first logical channel is mapped to zero or more SCSs (parameter sets) in the list of allowed serving cells; an allowed physical layer (PHY) priority index, which indicates that data of the first logical channel is mapped to a dynamic grant that indicates zero or more PHY priority indexes in the allowed PHY indexes; a maximum physical uplink shared channel (PUSCH) duration, which indicates that data of the first logical channel is mapped to an uplink grant with a PUSCH duration shorter than or equal to the maximum PUSCH duration; and media access control (MAC)-related parameters. Based on this information, the wireless device may transmit a message. The message may include at least one of the following: an RRC request message for small data transmission; and data of the first logical channel. For example, based on this information, the wireless device may transmit a message via a cell in the list of allowed serving cells. For example, based on this information, the wireless device may transmit a message via an SCS in the list of allowed SCSs.

[0379] In an example, the MAC-related parameters may include at least one of the following: channel access priority; logical channel priority; logical channel group identity; bucket size duration; bit rate multiplier; bit rate query prohibition timer; logical channel scheduling request (SR) mask; applied logical channel SR delay timer; SR identity; and prioritized bit rate. For example, the channel access priority may indicate an operation to be used for shared spectrum channel access on an uplink transmission. The SR identity may indicate a scheduling request configuration applicable to the first logical channel. The applied logical channel SR delay timer may indicate whether a delay timer is applied to the SR transmission of the logical channel. The logical channel group identity may be an identity of the logical channel group to which the first logical channel belongs. The bit rate query prohibition timer may be used for bit rate recommendation queries. The bit rate multiplier may be a bit rate multiplier for a recommended bit rate MAC CE. The logical channel priority may be used for logical channel prioritization. The channel access priority may be used for shared spectrum channel access operations on an uplink transmission. The bucket size duration may indicate how long uplink data of the logical channel is transmitted using the prioritized bit rate before reaching the bucket size value. The logical channel scheduling request SR mask may be used to control SR triggering when a configured uplink grant is available.

[0380] In an example, when the wireless device is in the RRC inactive state, the wireless device can transmit a message. When the wireless device is in the RRC inactive state, the wireless device can transmit a message. The wireless device can transmit a message during the RRC inactive state.

[0381] In an example, the wireless device can suspend the RRC connection based on an RRC release message. The RRC release message can include a suspension configuration. The suspension configuration can indicate to suspend the RRC connection.

[0382] In an example, the wireless device can transmit a message based on initiating small data transmission. The wireless device can initiate (or determine to initiate) small data transmission based on one or more conditions for the small data transmission being met. The one or more conditions can include that the logical channel of the data is a first logical channel. The one or more conditions can further include conditions for the small data transmission. The conditions for the small data transmission can include at least one of the following: EDT condition; and PUR condition. For example, the wireless device can use the configured grant for small data transmission to transmit a message based on the first logical channel being permitted to use the configured grant for small data transmission.

[0383] In an example, the base station can indicate to release a fourth logical channel configured for small data transmission. For example, the information can further indicate to release a fourth logical channel configured for small data transmission. For example, the information can indicate a logical channel identifier and release the logical channel configuration of the logical channel identifier. The indication can include indicating via at least one of the following: RRC release message; information. Based on the information, the wireless device can release the logical channel configuration.

[0384] In an example, the base station can indicate that a fifth logical channel is not permitted to use small data transmission. The information can further indicate that a fifth logical channel is not permitted to use small data transmission. For example, the information can indicate a logical channel identifier and the logical channel of the logical channel identifier not permitted for small data transmission. The indication can include indicating via at least one of the following: RRC release message; information. Based on the information, the wireless device can reconfigure the logical channel to not permit small data transmission.

[0385] In an example, based on an (RRC) release message indicating a transition to the RRC inactive state, the wireless device can transition to the RRC inactive state. For example, the wireless device can transition from the RRC connected state to the RRC inactive state; or from the RRC inactive state back to the RRC inactive state; or from the RRC idle state to the RRC inactive state.

[0386] In an example, the message may further include auxiliary parameters indicating a small data transmission on a first logical channel. The auxiliary parameters may further indicate that subsequent data is expected. The auxiliary parameters may include traffic information (e.g., traffic pattern) of the small data transmission. For example, the auxiliary parameters may include a buffer status report of the subsequent data.

[0387] In an example, a wireless device may store information based on an RRC release message. For example, when transitioning to the RRC inactive state (or the RRC idle state), the wireless device may store information based on the RRC release message. The wireless device may restore the stored information based on determining to initiate a small data transmission. For example, a wireless device in the RRC inactive state (or the RRC idle state) may restore the stored information based on determining to initiate a small data transmission. The first logical channel may be further configured to be used in the RRC inactive state.

[0388] In an example, based on the information, the wireless device may transmit an RRC request message including a small data transmission, and a message of data on the first logical channel. The message may be a message of the small data transmission. For example, based on the information, a wireless device in the RRC inactive state or the RRC idle state (e.g., a second RRC inactive state) may initiate a small data transmission. For example, based on updated information, the wireless device may determine whether to initiate a small data transmission. Based on the updated information, the wireless device may select data to be transmitted for the small data transmission. Based on the updated information, the wireless device may select radio resources (e.g., uplink grant) for the small data transmission. Based on the updated information, the wireless device may select / configure radio parameters (e.g., parameter set, subcarrier spacing, priority of the logical channel, MAC-related parameters) for the small data transmission.

[0389] In an example, the small data transmission may include at least one of the following: a small data transmission (or EDT) based on a random access control channel (RACH); and a small data transmission based on configured grant (CG) (or a small data transmission using PUR).

[0390] In an example, the base station may transmit information to the wireless device via an RRC release message. For example, the base station may transmit an RRC release message including the information to the wireless device. The base station may determine reconfiguration information. For example, when the wireless device is in the RRC connected state or the RRC inactive state or the RRC idle state, the base station may determine reconfiguration information. For example, the base station may determine reconfiguration information based on a request received from a core network entity to release or modify a radio bearer associated with the first logical channel. For example, an access and mobility management function (AMF) may send a request to the base station to release a radio bearer (or a PDU session) associated with the first logical channel.

[0391] For example, the base station may determine reconfiguration information based on a configured grant configuration that determines reconfiguration of small data transmission. Based on determining to reconfigure the configured grant configuration, the base station may reconfigure information of a logical channel associated with the reconfigured configured grant configuration.

[0392] For example, the base station may determine reconfiguration information based on identifying that a configured grant permitted for a logical channel is unavailable (or invalid) in the base station or a serving cell of the base station. For example, the base station may determine reconfiguration information based on information parameters (e.g., logical channel configuration parameters or RLC bearer configuration parameters) being invalid (or not supported). For example, the base station may determine reconfiguration information based on a first logical channel not being supported (not being accepted). For example, the base station may determine reconfiguration information based on radio capabilities associated with the first logical channel not being supported (not being accepted).

[0393] For example, a wireless device may receive an RRC release message indicating a transition to the RRC inactive state from a first base station. The wireless device in the RRC inactive state may transmit an RRC request message (e.g., an RRC resume request message) to a second base station. Based on receiving the RRC request message, the second base station may send a retrieve UE context request message to the first base station. In response to the retrieve context request message, the first base station may send a retrieve (UE) context response message including the (UE) context of the wireless device to the second base station. Based on the retrieve context response message, the second base station may determine at least one of the following: whether to accept configuration parameters (e.g., PDU session / radio bearer / logical channel or radio resources (configured grant) or radio capabilities) in the (UE) context; or which configuration parameters will be accepted / reused in the second base station. Based on this determination, the second base station may (determine) reconfigure the information.

[0394] In an example, releasing reconfiguration information includes at least one of the following: releasing a first logical channel; releasing or modifying configuration parameters associated with the first logical channel; releasing or modifying a configured grant associated with the first logical channel; and releasing or modifying radio capabilities associated with the first logical channel.

[0395] In an example, based on determining reconfiguration information, the base station may transmit information in the following cases: when transitioning the wireless device to the RRC inactive state or the RRC idle state; or when the wireless device is in the RRC inactive state or the RRC idle state. Based on this request, the base station may transmit information to the wireless device via an RRC release message.

[0396] In an example, a wireless device in the RRC inactive state or the RRC idle state may send an RRC request message to a base station. Based on the RRC request message, the base station may determine information for releasing or modifying a first logical channel. When in the RRC inactive state, the base station may transmit information to the wireless device. For example, based on a request from the AMF, the base station may send a paging message to a wireless device in the RRC inactive state (or the RRC idle state). Based on the paging message, the wireless device in the RRC inactive state may send an RRC request message to the base station. For example, based on a request from the AMF, the base station may wait until the wireless device sends an RRC request message. For example, in response to the RRC request message, the base station may transmit information to the wireless device.

[0397] Figure 23 An example of logical channel information for small data transmission is shown. The wireless device may receive an RRC release message from the base station, the message including logical channel information / configuration of a logical channel configured for small data transmission (information of the logical channel configured for small data transmission). The RRC release message may indicate transitioning the wireless device to the RRC inactive state (or the RRC idle state). The base station may determine (re)configuring the logical channel information / configuration of the logical channel configured for small data transmission. Based on this determination, the base station may transmit an RRC release message to the wireless device. Based on the RRC release message (or the logical channel information / configuration), the wireless device may store the logical channel information / configuration of the logical channel configured for small data transmission. Based on the RRC release message, the wireless device may transition to the RRC inactive state (or the RRC idle state). The transition may include at least one of the following: transitioning from the RRC connected state to the RRC inactive state; transitioning from the RRC inactive state back to the RRC inactive state; transitioning from the RRC idle state to the RRC inactive state.

[0398] In Figure 23 the example, based on the logical channel information / configuration, a wireless device in the RRC inactive state (or the RRC idle state) may perform small data transmission. For example, based on the logical channel information / configuration, a wireless device in the RRC inactive state may determine whether to initiate small data transmission. Based on the logical channel information / configuration, a wireless device in the RRC inactive state may determine whether to transmit data of the logical channel to the base station. Based on the logical channel information / configuration, a wireless device in the RRC inactive state may transmit data of the logical channel configured for small data transmission.

[0399] Figure 24An example of logical channel information for small data transmission in the RRC inactive state is shown. A wireless device in the RRC inactive state (or RRC idle state) may store information of logical channel A (e.g., logical channel configuration of logical channel A), which is configured for small data transmission in the RRC inactive state (or RRC idle state). The wireless device may access the base station via a cell of the base station. The wireless device may indicate to the base station that it does not intend to transition to the RRC connected state. For example, the wireless device may indicate this intention based on an RRC request message for updating the transmission indication RNA. The RRC request message may include the RNA update as a cause value. For example, the wireless device may indicate this intention based on a message for transmitting small data transmission, where the message includes at least one of the following: an RRC request message; (small) data; and auxiliary parameters indicating small data transmission.

[0400] In Figure 23 the example of, the base station may determine / intend to update the information A of the logical channel configured for small data transmission (logical channel information / configuration A). Based on this indication, the base station may transmit an RRC release message including the updated information (e.g., information B) to the wireless device without transitioning to the RRC connected state (when the wireless device is in the RRC inactive state). Based on the updated information, the wireless device may update the information A with the information B and store the updated information. Based on the RRC release message, the wireless device may transition to the RRC inactive state or the RRC idle state.

[0401] Figure 25An example of logical channel information for small data transmission in the RRC connected state is shown. When a wireless device is in the RRC connected state, the wireless device can receive information / configurations for communication in the RRC connected state from a base station. For example, when / while the wireless device is in the RRC connected state, the wireless device can receive an RRC reconfiguration message from the base station, and the RRC reconfiguration message includes first logical channel information / configurations for communication in the RRC connected state. The first logical channel information can be information of a first logical channel configured for communication in the RRC connected state. Based on the first logical channel information, the wireless device in the RRC connected state can communicate with the base station. The communication can include at least one of the following: transmitting data / signals to the base station and receiving data / signals from the base station. The wireless device can receive an RRC release message from the base station, and the RRC release message includes second logical channel information / configurations for small data transmission. For example, the base station can determine (re)configure / modify / update the second logical channel information / configurations for small data transmission. Based on this determination, the base station can transmit the RRC release message. The second logical channel information can be information of a second logical channel configured for small data transmission. Based on the second logical channel information, the wireless device in the RRC inactive state can perform small data transmission. Based on the second logical channel information, the wireless device in the RRC inactive state can initiate small data transmission. Based on the second logical channel information, the wireless device in the RRC inactive state can transmit or receive data from the base station.

[0402] The base station can send an RRC release message to the wireless device, and the RRC release message includes information on the logical channels configured for small data transmission. In the prior art, when a base station including a base station central unit (gNB-CU) and a base station distributed unit (gNB-DU) transmits an RRC release message to a wireless device, the base station central unit can transmit a UE context release command message including the RRC release message to the base station distributed unit. Based on the UE context release command message, the base station distributed unit can release the UE context of the wireless device. If a wireless device in the RRC inactive state (or RRC idle state) transmits a message for small data transmission, the base station distributed unit may need the information on the logical channels to process the message (e.g., transmit a response to the wireless device and transmit the data of the message to the base station center). For example, a wireless device in the RRC inactive state (or RRC idle state) uses (pre)-configured grant to transmit a message to the base station. Based on receiving the message, the base station distributed unit storing the configured grant configuration for small data transmission (e.g., PUR) may need the information on the logical channels associated with the configured grant configuration to process the message. The base station distributed unit can exchange signals with the base station central unit to obtain the information. This may result in signal overhead between the base station distributed unit and the base station central unit. This may also result in a delay in receiving a response to the message and power consumption of the wireless device performing small data transmission.

[0403] Exemplary embodiments can support the base station central unit to transmit the information on the logical channels configured for small data transmission to the base station distributed unit via a (UE) context release command message. Based on receiving the information, the base station distributed unit can store the information when the wireless device is in the RRC inactive state (or RRC idle state) and restore / use the information during sm...

Claims

1. A communication method, the method comprises: receiving, by a wireless device in RRC connected state, a Radio Resource Control (RRC) reconfiguration message from a base station, the RRC reconfiguration message including a first logical channel configuration for transmission of data of a first logical channel in the RRC connected state, wherein the RRC reconfiguration message includes cell group configuration parameters of a primary cell group; receiving, by the wireless device, an RRC release message from the base station, the RRC release message including a second logical channel configuration for transmission of data of a second logical channel in RRC inactive state or RRC idle state, wherein the second logical channel configuration includes a permitted configured grant list, the permitted configured grant list indicating that the data of the second logical channel is mapped to a configured grant configuration of a configured grant for transmission in the RRC inactive state or the RRC idle state; and transmitting, by the wireless device in the RRC inactive state or the RRC idle state, the data of the second logical channel to the base station using a small data transmission procedure.

2. The method according to claim 1, wherein the configured grant configuration is included in the RRC release message.

3. The method according to any one of claims 1 to 2, wherein the permitted configured grant list includes an index of the configured grant configuration of the configured grant as an indication of permitting the second logical channel to use the configured grant.

4. The method according to claim 1, further comprising transitioning, by the wireless device, to the RRC inactive state or the RRC idle state based on receiving the RRC release message from the base station.

5. The method according to claim 1, wherein the small data transmission procedure includes a procedure for transmission in the RRC inactive state or the RRC idle state.

6. A wireless device, the wireless device includes one or more processors and a memory storing a computer program, the computer program when executed by the one or more processors causes the wireless device to perform the method according to any one of claims 1 to 5.

7. A non-transitory computer-readable medium, the non-transitory computer-readable medium includes a computer program, the computer program when executed by one or more processors causes the one or more processors to perform the method according to any one of claims 1 to 5.

8. A communication method, the method comprises: transmitting, by a base station, a Radio Resource Control (RRC) reconfiguration message to a wireless device in RRC connected state, the RRC reconfiguration message including a first logical channel configuration for transmission of data of a first logical channel in the RRC connected state, wherein the RRC reconfiguration message includes cell group configuration parameters of a primary cell group; Transmit an RRC release message from the base station to the wireless device, the RRC release message including a second logical channel configuration for transmitting data of a second logical channel in an RRC inactive state or an RRC idle state, wherein the second logical channel configuration includes a permitted configured grant list, the permitted configured grant list indicating that the data of the second logical channel is mapped to a configured grant configuration of a configured grant for transmission in the RRC inactive state or the RRC idle state; And Receive, by the base station from the wireless device in the RRC inactive state or the RRC idle state, the data of the second logical channel using a small data transmission procedure.

9. The method according to claim 8, wherein the configured grant configuration is included in the RRC release message.

10. The method according to any one of claims 8 to 9, wherein the permitted configured grant list includes an index of the configured grant configuration of the configured grant as an indication of permitting the second logical channel to use the configured grant.

11. The method according to claim 8, further comprising, based on transmitting the RRC release message to the wireless device, the base station transitioning the wireless device to the RRC inactive state or the RRC idle state.

12. The method according to claim 8, wherein the small data transmission procedure includes a procedure for transmission in the RRC inactive state or the RRC idle state.

13. A base station, the base station including one or more processors and a memory storing a computer program, the computer program, when executed by the one or more processors, causing the base station to perform the method according to any one of claims 8 to 12.

14. A non-transitory computer-readable medium, the non-transitory computer-readable medium including a computer program, the computer program, when executed by one or more processors, causing the one or more processors to perform the method according to any one of claims 8 to 12.

15. A communication system, Comprising: A base station, the base station including one or more processors and a memory storing a computer program, the computer program, when executed by the one or more processors, causing the base station to: Transmit a radio resource control (RRC) reconfiguration message to a wireless device in an RRC connected state, the RRC reconfiguration message including a first logical channel configuration for transmitting data of a first logical channel in the RRC connected state, wherein the RRC reconfiguration message includes cell group configuration parameters of a primary cell group; Transmit an RRC release message to the wireless device, the RRC release message including a second logical channel configuration for transmission of data of a second logical channel in an RRC inactive state or an RRC idle state, wherein the second logical channel configuration includes a permitted configured grant list, the permitted configured grant list indicating that the data of the second logical channel is mapped to a configured grant configuration of a configured grant for transmission in the RRC inactive state or the RRC idle state; And Receive the data of the second logical channel from the wireless device in the RRC inactive state or the RRC idle state; And The wireless device, wherein the wireless device includes one or more processors and a memory storing a computer program, the computer program when executed by the one or more processors causes the wireless device to: Receive an RRC reconfiguration message from the base station; Receive an RRC release message from the base station; And Transmit the data of the second logical channel to the base station using a small data transmission procedure.

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