Program for transferring small data

Abstract

A base station distributed unit receives an RRC request message of a small data transfer (SDT) procedure and uplink data associated with the SDT procedure from a wireless device that is not in a radio resource control (RRC) connection state through the base station distributed unit. The base station distributed unit receives a message indicating the SDT procedure from a base station central unit. The base station distributed unit sends the uplink data to the base station central unit based on the message.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 133,015, filed on December 31, 2020, which is hereby incorporated by reference in its entirety. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0004] Figure 1A and Figure 1B An exemplary mobile communication network is shown in which embodiments of the present disclosure may be implemented.

[0005] Figure 2A and Figure 2B New Radio (NR) user plane and control plane protocol stacks are shown separately.

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

[0007] Figure 4A Shows the flow Figure 2A Figure 2 shows an exemplary downlink data flow of the NR user plane protocol stack.

[0008] Figure 4B An exemplary format of a MAC subheader in a MAC PDU is shown.

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

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

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

[0012] Figure 8 An exemplary configuration of time slots in the time and frequency domain of an NR carrier is shown.

[0013] Fig. 9 An example of bandwidth adaptation using three configured BWPs for NR carriers is shown.

[0014] Fig. 10A Three carrier aggregation configurations with two component carriers are shown.

[0015] Fig. 10B An example of how aggregated cells may be configured into one or more PUCCH groups is shown.

[0016] Fig.11A An example of SS / PBCH block structure and location is shown.

[0017] Fig. 11B An example of CSI-RS mapped in the time and frequency domains is shown.

[0018] Fig. 12A and Fig. 12B Three examples of downlink and uplink beam management procedures are shown respectively.

[0019] Fig.13A , Fig. 13B and Fig. 13C A four-step contention-based random access procedure, a two-step contention-free random access procedure and another two-step random access procedure are shown respectively.

[0020] Fig.14A An example of a CORESET configuration for the bandwidth portion is shown.

[0021] Fig. 14B An example of CCE to REG mapping for DCI transmission on CORESET and PDCCH processing is shown.

[0022] Fig.15 An example of a wireless device in communication with a base station is shown.

[0023] Fig.16A , Fig. 16B , Fig. 16C and Fig.16D Exemplary structures for uplink and downlink transmissions are shown.

[0024] Fig.17 are diagrams of aspects of examples of the disclosure.

[0025] Fig.18 are diagrams of aspects of examples of the disclosure.

[0026] Fig.19 are diagrams of aspects of examples of the disclosure.

[0027] Fig. 20 are diagrams of aspects of examples of the disclosure.

[0028] Fig.21 are diagrams of aspects of examples of the disclosure.

[0029] Fig. 22 are diagrams of aspects of examples of the disclosure.

[0030] Fig.23 are diagrams of aspects of examples of the disclosure.

[0031] Fig.24 are diagrams of aspects of examples of the disclosure.

[0032] Fig.25 are diagrams of aspects of examples of the disclosure.

[0033] Fig.26 are diagrams of aspects of examples of the disclosure.

[0034] Fig. 27 are diagrams of aspects of examples of the disclosure.

[0035] Fig.28 are diagrams of aspects of examples of the disclosure.

[0036] Fig.29 are diagrams of aspects of examples of the disclosure.

[0037] Fig.30 are diagrams of aspects of examples of the disclosure.

[0038] Fig.31 are diagrams of aspects of examples of the disclosure.

[0039] Fig.32 are diagrams of aspects of examples of the disclosure. DETAILED DESCRIPTION

[0040] 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 environments and scenarios. It will be apparent to those skilled in the relevant art that various changes in form and detail can be made therein 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 described exemplary embodiments. The embodiments of the present disclosure will be described with reference to the accompanying drawings. Restrictions, features and / or elements from the disclosed exemplary embodiments can be combined to create additional embodiments within the scope of the present disclosure. Any figure highlighting functionality and advantages is provided only for illustrative purposes. The disclosed architecture is flexible and configurable enough so that it can be utilized in a manner different from that shown. For example, the actions listed in any flow chart can be reordered or only optionally used in certain embodiments.

[0041] Embodiments may be configured to operate as desired. 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 mechanism may be executed. Exemplary criteria may be based at least in part 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 may be applied. Therefore, exemplary embodiments that selectively implement the disclosed protocol may be implemented.

[0042] A base station may communicate with a mixture of wireless devices. A wireless device and / or base station may support multiple technologies and / or multiple versions of the same technology. A wireless device may have certain specific capabilities, depending on the wireless device category and / or capabilities. When the present disclosure refers to a base station communicating with multiple wireless devices, the present disclosure may refer to a subset of the total wireless devices in the coverage area. For example, the present disclosure may refer to multiple wireless devices of a given LTE or 5G version with a given capability and in a given sector of a base station. The multiple wireless devices in the present disclosure may refer to a selected plurality of wireless devices, and / or a subset of the total wireless devices in the coverage area that perform according to the disclosed methods, etc. There may be multiple base stations or multiple wireless devices in the coverage area that may not comply with the disclosed methods, for example, these wireless devices or base stations may perform based on older versions of LTE or 5G technology.

[0043] In the present disclosure, "a" and "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 the present 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 a suitable possibility among multiple suitable possibilities that may or may not be used for one or more embodiments in various embodiments. As used herein, the terms "comprising" and "consisting of..." list one or more components of the element being described. The terms "comprising" and "including" are interchangeable and do not exclude that unlisted components are included in the element being described. In contrast, "consisting of..." provides a complete listing of the one or more components of the element being described. As used herein, the term "based on" should be interpreted as "based at least in part on" rather than, for example, "based only on". As used herein, the term "and / or" represents any possible combination of the listed elements. For example, “A, B and / or C” can mean A; B; C; A and B; A and C; B and C; or A, B and C.

[0044] 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") indicates that the phrase after the term "based on" is an example of one of multiple suitable possibilities that may or may not be used for one or more different embodiments. The phrase "in response to" (or equivalently "at least in response to") indicates that the phrase after the phrase "in response to" is an example of one of multiple suitable possibilities that may or may not be used for one or more different embodiments. The phrase "depends on" (or equivalently "at least depends on") indicates that the phrase after the phrase "depends on" is an example of one of multiple suitable possibilities that may or may not be used for one or more different embodiments. The phrase "adopting / using" (or equivalently "at least adopting / using") indicates that the phrase after the phrase "adopting / using" is an example of one of multiple suitable possibilities that may or may not be used for one or more different embodiments.

[0045] The term configured may relate to the capabilities of a device, whether the device is in an operational state or a non-operational state. "Configured" may also mean a specific setting in a device that affects the operational characteristics of the device, whether the device is in an operational state or a non-operational state. In other words, hardware, software, firmware, registers, memory values, etc. may be "configured" within a device to provide specific characteristics to the device, whether the device is in an operational state or a non-operational state. Terms such as "a control message caused in a device" may 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 operational state or a non-operational state.

[0046] In the present disclosure, a parameter (or equivalently referred to as a field or information element: IE) may include one or more information objects, and an information object may 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 a parameter of the multiple parameters is in at least one of the one or more messages, but not necessarily in each of the one or more messages.

[0047] Many of the features set forth are described as optional, either by the use of "may" or by the use of parentheses. For the sake of brevity and readability, the present disclosure does not explicitly recite every permutation that can be obtained by selecting from the set of optional features. The present disclosure should be interpreted as explicitly disclosing all such permutations. For example, a system described as having three optional features can be embodied in seven different ways, i.e., having only one of the three possible features, having any two of the three possible features, or having three of the three possible features.

[0048] Many elements described in the disclosed embodiments can be implemented as modules.Modules are defined here as elements that perform defined functions and have defined interfaces to other elements.Modules described in the present disclosure can be implemented by hardware, software, firmware, wetware (for example, hardware with biological elements) in combination with hardware, or a combination thereof, all of which can be equivalent in behavior.For example, a module can be implemented as a software routine written in a computer language, which is 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 LabVIEWMathScript).It is possible to implement a module using physical hardware that incorporates discrete or programmable analog, digital and / or quantum hardware.Examples of programmable hardware include: computers, microcontrollers, microprocessors, application specific integrated circuits (ASICs); field programmable gate arrays (FPGAs); and complex programmable logic devices (CPLDs).Computers, microcontrollers, and microprocessors are programmed using languages ​​such as assembly, C, C++, etc. FPGAs, ASICs, and CPLDs are often programmed using a hardware description language (HDL), such as VHSIC Hardware Description Language (VHDL) or Verilog, which configures the connections between less functional internal hardware blocks on the programmable device. The mentioned techniques are often used in combination to achieve the results of the functional blocks.

[0049] Figure 1A 1 shows an example of a mobile communication network 100 in which embodiments of the present disclosure may be implemented. The mobile communication network 100 may be, for example, a public land mobile network (PLMN) operated by a network operator. Figure 1A As shown, the mobile communication network 100 includes a core network (CN) 102 , a radio access network (RAN) 104 , and wireless devices 106 .

[0050] The CN 102 may 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, for the wireless device 106. As part of the interface functionality, the CN 102 may set up an end-to-end connection between the wireless device 106 and the one or more DNs, authenticate the wireless device 106, and provide charging functionality.

[0051] The RAN 104 may connect the CN 102 to the wireless device 106 via radio communications over an air interface. As part of the radio communications, the RAN 104 may provide scheduling, radio resource management, and retransmission protocols. The direction of communication from the RAN 104 to the wireless device 106 over the air interface is referred to as downlink, while the direction of communication from the wireless device 106 to the RAN 104 over the air interface is referred to as uplink. Downlink transmissions may be separated from uplink transmissions using frequency division duplex (FDD), time division duplex (TDD), and / or some combination of the two duplex technologies.

[0052] The term "wireless device" may be used throughout this disclosure to mean and encompass any mobile or fixed (non-mobile) device that requires or can use wireless communication. For example, a wireless device may be a phone, a smartphone, a tablet, a computer, a laptop, a sensor, a meter, a wearable device, an Internet of Things (IoT) device, a vehicle roadside unit (RSU), a relay node, a car, 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.

[0053] The RAN 104 may include one or more base stations (not shown). The term "base station" may be used throughout this disclosure to mean and encompass: a Node B (associated with UMTS and / or 3G standards); an evolved Node B (eNB, associated with E-UTRA and / or 4G standards); a remote radio head (RRH); a baseband processing unit coupled to one or more RRHs; a repeater node or relay node used to extend the coverage area of ​​a donor node; a next generation evolved Node B (ng-eNB); a generation Node B (gNB, associated with NR and / or 5G standards); an access point (AP, associated with, for example, WiFi or any other suitable wireless communication standard); and / or any combination thereof. A base station may include at least one gNB central unit (gNB-CU) and at least one gNB distributed unit (gNB-DU).

[0054] The base stations included in the RAN 104 may include one or more sets of antennas for communicating with the wireless devices 106 over the air interface. For example, one or more of the base stations may include three sets of antennas to control three cells (or sectors) respectively. The size of the cell may be determined by the range at 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 stations may together provide radio coverage to the wireless devices 106 over a wide geographic area to support wireless device mobility.

[0055] In addition to three-sector sites, other implementations of the base station are possible. For example, one or more of the base stations in the RAN 104 may be implemented as a sectorized site with more or less than three sectors. One or more of the base stations in the RAN 104 may be implemented as an access point, a baseband processing unit coupled to several remote radio heads (RRHs), and / or a repeater or relay node 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 baseband processing unit pool or virtualized. The repeater node may amplify and rebroadcast the radio signal received from the donor node. The relay node may perform the same / similar functions as the repeater node, but may decode the radio signal received from the donor node to eliminate noise before amplifying and rebroadcasting the radio signal.

[0056] The RAN 104 may be deployed as a homogeneous network of macrocell base stations with similar antenna types and similar high levels of transmit power. The RAN 104 may be deployed as a heterogeneous network. In a heterogeneous network, a small cell base station may be used to provide a small coverage area, such as a coverage area that overlaps with a relatively large coverage area provided by a macrocell base station. Small coverage areas may be provided in areas with high data traffic (or so-called "hot spots") or in areas where macrocell coverage is weak. Examples of small cell base stations include, in descending order of coverage area: microcell base stations, picocell base stations, and femtocell base stations or home base stations.

[0057] The Third Generation Partnership Project (3GPP) was established in 1998 to Figure 1A 3GPP provides global specification standardization for mobile communication networks similar to the mobile communication network 100 in the mobile communication network 100. To date, 3GPP has developed specifications for three generations of mobile networks: the third generation (3G) network known as the Universal Mobile Telecommunications System (UMTS), the fourth generation (4G) network known as the Long Term Evolution (LTE), and the fifth generation (5G) network known as the 5G System (5GS). Embodiments of the present disclosure are described with reference to the RAN of the 3GPP 5G network known as the Next Generation RAN (NG-RAN). These embodiments may be applicable to the RAN of other mobile communication networks, such as Figure 1A The RAN 104 in 5G networks, the RAN of early 3G and 4G networks, and those of yet-to-be-specified future networks (e.g., 3GPP 6G networks). The NG-RAN implements the 5G radio access technology known as New Radio (NR) and may be configured to implement 4G radio access technology or other radio access technologies, including non-3GPP radio access technologies.

[0058] Figure 1B Another exemplary mobile communication network 150 in which embodiments of the present disclosure may be implemented is shown. The mobile communication network 150 may be, for example, a PLMN operated by a network operator. Figure 1B As shown in FIG. 1 , the mobile communication network 150 includes a 5G core network (5G-CN) 152, an NG-RAN 154, and UEs 156A and 156B (collectively referred to as UE 156). Figure 1A The corresponding components described are implemented and operate in the same or similar manner.

[0059] 5G-CN 152 provides an interface to one or more DNs, such as a public DN (e.g., the Internet), a private DN, and / or an operator's internal DN, to UE 156. As part of the interface function, 5G-CN 152 may set up an end-to-end connection between UE 156 and the one or more DNs, authenticate UE 156, and provide charging functions. Compared to the CN of the 3GPP 4G network, the basis of 5G-CN152 may be a service-based architecture. This means that the architecture of the nodes constituting 5G-CN 152 may be defined as network functions that provide services to other network functions via interfaces. The network functions of 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).

[0060] like Figure 1B As shown, 5G-CN 152 includes an access and mobility management function (AMF) 158A and a user plane function (UPF) 158B. For ease of explanation, Figure 1BThey are shown as one component AMF / UPF 158 in FIG. UPF 158B can act as a gateway between NG-RAN 154 and the one or more DNs. UPF 158B can perform functions such as: packet routing and forwarding, packet inspection and user plane policy rule enforcement, service usage reporting, uplink classification to support routing of service flows to the one or more DNs, user plane quality of service (QoS) processing (e.g., packet filtering, gating, uplink / downlink rate enforcement and uplink service verification), downlink packet buffering and downlink data notification triggering. UPF 158B can act as an anchor point for intra / inter-radio access technology (RAT) mobility, an external protocol (or packet) data unit (PDU) session point interconnected with the one or more DNs, and / or a fulcrum for supporting multi-host PDU sessions. UE 156 can be configured to receive services through a PDU session, which is a logical connection between the UE and the DN.

[0061] The AMF 158A may perform functions such as: non-access stratum (NAS) signaling termination, NAS signaling security, access stratum (AS) security control, inter-CN node signaling for mobility between 3GPP access networks, idle mode UE reachability (e.g., control and execution of paging retransmissions), registration area management, intra-system and inter-system mobility support, access authentication, access authorization including roaming rights verification, mobility management control (subscription and policy), network slicing support and / or session management function (SMF) selection. NAS may refer to functions operating between the CN and the UE, and AS may refer to functions operating between the UE and the RAN.

[0062] 5G-CN 152 may include Figure 1B , one or more additional network functions shown in . For example, 5G-CN 152 may include one or more of the following: session management function (SMF), NR repository function (NRF), policy control function (PCF), network exposure function (NEF), unified data management (UDM), application function (AF) and / or authentication server function (AUSF).

[0063] The NG-RAN 154 may connect the 5G-CN 152 to the UE 156 via radio communications over an air interface. The NG-RAN 154 may include: one or more gNBs, shown as gNB 160A and gNB 160B (collectively referred to as gNB 160); and / or one or more ng-eNBs, shown as ng-eNB 162A and ng-eNB 162B (collectively referred to as ng-eNB 162). The gNB 160 and ng-eNB 162 may be more generally referred to as base stations. The gNB 160 and ng-eNB 162 may include one or more groups of antennas for communicating with the UE 156 over an air interface. For example, one or more gNBs in the gNB 160 and / or one or more ng-eNBs in the ng-eNB 162 may include three groups of antennas to control three cells (or sectors), respectively. The cells of gNB 160 and ng-eNB 162 may together provide radio coverage to UE 156 over a wide geographic area to support UE mobility.

[0064] like Figure 1B As shown in FIG, gNB 160 and / or ng-eNB 162 may be connected to 5G-CN 152 via an NG interface and to other base stations via an Xn interface. The NG and Xn interfaces may be established using a direct physical connection and / or an indirect connection through an underlying transport network such as an Internet Protocol (IP) transport network. gNB 160 and / or ng-eNB 162 may be connected to UE 156 via a Uu interface. For example, Figure 1B As shown in FIG. 1 , gNB 160A may be connected to UE 156A via a Uu interface. NG, Xn, and Uu interfaces are associated with a protocol stack. The protocol stack associated with the interface may be composed of Figure 1B The network elements in a network are used to exchange data and signaling messages and may include two planes: a user plane and a control plane. The user plane may process data that the user is interested in. The control plane may process signaling messages that the network elements are interested in.

[0065] The gNB 160 and / or ng-eNB 162 may be connected to one or more AMF / UPF functions of the 5G-CN 152, such as the AMF / UPF 158, by means of one or more NG interfaces. For example, the gNB 160A may be connected to the UPF 158B of the AMF / UPF 158 by means of a NG user plane (NG-U) interface. The NG-U interface may provide delivery of user plane PDUs (e.g., non-guaranteed delivery) between the gNB 160A and the UPF 158B. The gNB 160A may be connected to the AMF 158A by means of a NG control plane (NG-C) interface. The NG-C interface may provide, for example, NG interface management, UE context management, UE mobility management, delivery of NAS messages, paging, PDU session management, and configuration delivery and / or warning message transmission.

[0066] The gNB 160 may provide NR user plane and control plane protocol terminations to the UE 156 via a Uu interface. For example, the gNB 160A may provide NR user plane and control plane protocol terminations to the UE 156A via a Uu interface associated with the first protocol stack. The ng-eNB 162 may provide Evolved UMTS Terrestrial Radio Access (E-UTRA) user plane and control plane protocol terminations to the UE 156 via a Uu interface, where E-UTRA refers to a 3GPP 4G radio access technology. For example, the ng-eNB 162B may provide E-UTRA user plane and control plane protocol terminations to the UE 156B via a Uu interface associated with the second protocol stack.

[0067] 5G-CN 152 is described as being configured to handle both NR and 4G radio access. One of ordinary skill in the art will appreciate that it is possible for NR to be connected to a 4G core network in a mode known as "non-standalone operation". In non-standalone operation, the 4G core network is used to provide (or at least support) control plane functions (e.g., initial access, mobility, and paging). Although Figure 1B Only one AMF / UPF 158 is shown in the figure, but a gNB or ng-eNB can be connected to multiple AMF / UPF nodes to provide redundancy and / or load sharing across the multiple AMF / UPF nodes.

[0068] As discussed, Figure 1B The interfaces between network elements in a network (e.g., Uu, Xn, and NG interfaces) may be associated with a protocol stack used by the network elements to exchange data and signaling messages. The protocol stack may include two planes: a user plane and a control plane. The user plane may process data of interest to the user, while the control plane may process signaling messages of interest to the network elements.

[0069] Figure 2A and Figure 2B Examples of NR user plane and NR control plane protocol stacks for the Uu interface between UE 210 and gNB 220 are shown, respectively. Figure 2A and Figure 2B The protocol stack shown in can be used with e.g. Figure 1B The protocol stacks of the Uu interface between UE156A and gNB 160A shown in are the same or similar.

[0070] Figure 2A An NR user plane protocol stack including five layers implemented in a UE 210 and a gNB 220 is shown. At the bottom of the protocol stack, a physical layer (PHY) 211 and 221 may provide transport services to higher layers of the protocol stack and may correspond to layer 1 of the open system interconnection (OSI) model. The next four protocols above the PHY 211 and 221 include a medium access control layer (MAC) 212 and 222, a radio link control layer (RLC) 213 and 223, a packet data convergence protocol layer (PDCP) 214 and 224, and a service data application protocol layer (SDAP) 215 and 225. Together, these four protocols may constitute layer 2 or the data link layer of the OSI model.

[0071] Figure 3 An example of services provided between protocol layers of the NR user plane protocol stack is shown. Figure 2A and Figure 3 Starting from the top of , SDAPs 215 and 225 can perform QoS flow processing. UE 210 can receive services through a PDU session, which can be a logical connection between UE 210 and a DN. A 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 delay, data rate, and / or error rate). SDAPs 215 and 225 can perform mapping / demapping between the one or more QoS flows and one or more data radio bearers. The mapping / demapping between the QoS flows and the data radio bearers 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 flows and the data radio bearers through reflective mapping or control signaling received from the gNB 220. For reflective mapping, the SDAP 225 at the gNB 220 may mark downlink packets with a QoS flow indicator (QFI), which may be observed by the SDAP 215 at the UE 210 to determine the mapping / demapping between QoS flows and data radio bearers.

[0072] The PDCP 214 and 224 may perform header compression / decompression to reduce the amount of data that needs to be transmitted over the air interface, may perform encryption / decryption to prevent unauthorized decoding of data transmitted over the air interface, and may perform integrity protection to ensure that control messages originate from the intended source. The PDCP 214 and 224 may perform retransmission of undelivered packets, in-sequence delivery and reordering of packets, and removal of duplicate received packets due to, for example, intra-gNB handovers. The PDCP 214 and 224 may perform packet repetition to increase the likelihood that a packet is received, and remove any duplicate packets at the receiver. Packet repetition may be applicable to services that require high reliability.

[0073] although Figure 3 Not shown, but PDCP 214 and 224 can perform mapping / de-mapping between split radio bearers and RLC channels in a dual connectivity scenario. Dual connectivity is a technology that allows a UE to connect to two cells or more generally to two cell groups: a primary cell group (MCG) and a secondary cell group (SCG). 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 a cell group in dual connectivity. PDCP 214 and 224 can map / demapped split radio bearers between RLC channels belonging to a cell group.

[0074] RLC 213 and 223 can perform segmentation, retransmission through 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 described. RLC configuration can be based on each logical channel, independent of parameter sets and / or transmission time interval (TTI) duration. As shown in FIG. Figure 3 As shown in FIG. 1 , RLC 213 and 223 may provide RLC channels as services to PDCP 214 and 224, respectively.

[0075] The MAC 212 and 222 may perform multiplexing / demultiplexing of logical channels and / or mapping between logical channels and transport channels. The multiplexing / demultiplexing may include multiplexing / demultiplexing data units belonging to the one or more logical channels into / from a transport block (TB) delivered to / from the PHY 211 and 221. The MAC 222 may be configured to perform scheduling, scheduling information reporting, and priority handling between UEs with the aid of dynamic scheduling. Scheduling may be performed in the gNB 220 (at the MAC 222) for downlink and uplink. The MAC 212 and 222 may be configured to perform error correction by 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 the UE 210 with the aid of logical channel prioritization, and / or padding. The MAC 212 and 222 may support one or more parameter sets and / or transmission timing. In an example, mapping restrictions in logical channel prioritization may control which parameter sets and / or transmission timings a logical channel may use. Figure 3 As shown, MAC 212 and 222 may provide logical channels as services to RLC 213 and 223 .

[0076] PHY 211 and 221 can perform mapping of transport channels to physical channels and digital and analog signal processing functions for sending and receiving information over the air interface. These digital and analog signal processing functions may include, for example, encoding / decoding and modulation / demodulation. PHY 211 and 221 can perform multi-antenna mapping. Figure 3 As shown in , PHY 211 and 221 may provide one or more transport channels as a service to MAC 212 and 222 .

[0077] Figure 4A An exemplary downlink data flow through the NR user plane protocol stack is shown. Figure 4A 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 the gNB 220 is shown. The uplink data flow flowing through the NR user plane protocol stack can be the same as Figure 4A The downlink data flow is similar to that depicted in .

[0078] Figure 4A The downlink data flow of starts when SDAP 225 receives three IP packets from one or more QoS flows and maps the three packets to radio bearers. Figure 4A In the SDAP header (in Figure 4AThe data unit from / to a higher protocol layer is called a service data unit (SDU) of the lower protocol layer, and the data unit to / from a lower protocol layer is called a protocol data unit (PDU) of the higher protocol layer. Figure 4A As shown in , the data unit from SDAP 225 is the SDU of the lower protocol layer PDCP 224 and is the PDU of SDAP 225.

[0079] Figure 4A The remaining protocol layers in can perform their associated functions (e.g., Figure 3 ), add the corresponding headers, and forward their corresponding outputs to the next lower layer. For example, PDCP 224 may perform IP header compression and encryption, and forward its output to RLC 223. RLC 223 may optionally perform segmentation (e.g., Figure 4A 222) and forwards its output to MAC 222. MAC 222 may multiplex many RLC PDUs and may attach MAC subheaders to the RLC PDUs to form a transport block. In NR, MAC subheaders may be distributed throughout the MAC PDU, as shown in FIG. Figure 4A In LTE, the MAC subheader can be located entirely at the beginning of the MAC PDU. The NR MAC PDU structure can reduce processing time and associated latency because the MAC PDU subheader can be calculated before assembling the complete MAC PDU.

[0080] Figure 4B An exemplary format of a MAC subheader in a MAC PDU is shown. The MAC subheader includes: an SDU length field for indicating the length (e.g., in bytes) of the MAC SDU to which the MAC subheader corresponds; a logical channel identifier (LCID) field for identifying the logical channel from which the MAC SDU originates to assist in the demultiplexing process; a flag (F) for indicating the size of the SDU length field; and a reserved bit (R) field for future use.

[0081] Figure 4B Further shown is a MAC Control Element (CE) inserted into the MAC PDU by a MAC (such as MAC 223 or MAC 222). For example, Figure 4B Two MAC CEs are shown inserted into the MAC PDU. Figure 4B) and inserting a MAC CE at the end of a MAC PDU for uplink transmission. MAC CE may be used for in-band control signaling. Exemplary MAC CEs include: scheduling-related MAC CEs, such as buffer status reports and power headroom reports; activation / deactivation MAC CEs, such as those used for PDCP duplicate detection, channel state information (CSI) reporting, sounding reference signal (SRS) transmission, and activation / deactivation of previously configured components; discontinuous reception (DRX)-related MAC CEs; timing advance MAC CEs; and random access-related MAC CEs. A MAC subheader having a format similar to that described for a MAC SDU may be present before the MAC CE, and the MAC CE may be identified with a reserved value in the LCID field that indicates the type of control information included in the MAC CE.

[0082] Before describing the NR control plane protocol stack, the mapping between logical channels, transport channels, and physical channels and 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 below.

[0083] Figure 5A and Figure 5B The mapping between logical channels, transport channels and physical channels is shown for downlink and uplink respectively. Information is passed through channels between RLC, MAC and PHY of the NR protocol stack. Logical channels can be used between RLC and 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 specific UE, or as common logical channels that can be used by more than one UE. Logical channels can also be defined by the type of information they carry. The set of logical channels defined by NR includes, for example:

[0084] - Paging Control Channel (PCCH), which is used to carry paging messages used to page UEs whose location is unknown to the network at the cell level;

[0085] - 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 (SIBs), which can be used by UEs to obtain information about how a cell is configured and how it operates within the cell;

[0086] - Common Control Channel (CCCH), which is used to carry control messages and random access;

[0087] - a dedicated control channel (DCCH) used to carry control messages to / from a specific UE to configure the UE; and

[0088] - Dedicated Traffic Channel (DTCH), which is used to carry user data to / from a specific UE.

[0089] 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:

[0090] - Paging Channel (PCH), which is used to carry paging messages originating from PCCH;

[0091] - Broadcast Channel (BCH), which is used to carry the MIB from the BCCH;

[0092] - Downlink Shared Channel (DL-SCH), which is used to carry downlink data and signaling messages, including SIBs from BCCH;

[0093] - Uplink Shared Channel (UL-SCH), which is used to carry uplink data and signaling messages; and

[0094] - Random Access Channel (RACH), which is used to allow a UE to contact the network without any previous scheduling.

[0095] The PHY may use physical channels to pass information between processing levels of the PHY. A physical channel may have a set of associated time-frequency resources for carrying information of one or more transport channels. The PHY may generate control information to support low-level operation of the PHY and provide control information to lower levels of the PHY via physical control channels (referred to as L1 / L2 control channels). The set of physical channels and physical control channels defined by NR includes, for example:

[0096] - Physical Broadcast Channel (PBCH), which is used to carry the MIB from the BCH;

[0097] - Physical Downlink Shared Channel (PDSCH), which is used to carry downlink data and signaling messages from DL-SCH and paging messages from PCH;

[0098] - Physical Downlink Control Channel (PDCCH), which is used to carry downlink control information (DCI), which may include downlink scheduling commands, uplink scheduling grants, and uplink power control commands;

[0099] - Physical Uplink Shared Channel (PUSCH), which is used to carry uplink data and signaling messages from the UL-SCH, and in some cases uplink control information (UCI) as described below;

[0100] - Physical Uplink Control Channel (PUCCH), which is used to carry UCI, which may include HARQ acknowledgment, channel quality indicator (CQI), precoding matrix indicator (PMI), rank indicator (RI) and scheduling request (SR); and

[0101] - Physical Random Access Channel (PRACH), which is used for random access.

[0102] Similar to the physical control channel, the physical layer generates physical signals to support the lower-level operations of the physical layer. Figure 5A and Figure 5B As shown in , 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.

[0103] Figure 2B An exemplary NR control plane protocol stack is shown. Figure 2B As shown in , the NR control plane protocol stack may 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 instead has radio resource control (RRC) 216 and 226 and NAS protocols 217 and 237 at the top of the NR control plane protocol stack.

[0104] The NAS protocols 217 and 237 may provide control plane functions between the UE 210 and the AMF 230 (e.g., AMF 158A) or more generally between the UE 210 and the CN. The NAS protocols 217 and 237 may provide control plane functions between the UE 210 and the AMF 230 via signaling messages referred to as NAS messages. There is no direct path between the UE 210 and the AMF 230 through which NAS messages may be transmitted. NAS messages may be transmitted using the AS of the Uu and NG interfaces. The NAS protocols 217 and 237 may provide control plane functions such as authentication, security, connection setup, mobility management, and session management.

[0105] The RRCs 216 and 226 may provide control plane functions between the UE 210 and the gNB 220 or more generally between the UE 210 and the RAN. The RRCs 216 and 226 may provide control plane functions between the UE 210 and the gNB 220 via signaling messages referred to as RRC messages. The RRC messages may be transported between the UE 210 and the RAN using signaling radio bearers and the same / similar PDCP, RLC, MAC, and PHY protocol layers. The MAC may multiplex control plane and user plane data into the same transport block (TB). The RRC 216 and 226 may provide control plane functions such as: broadcast of system information related to AS and NAS; paging initiated by CN or RAN; establishment, maintenance, and release of an RRC connection between UE 210 and RAN; security functions including key management; establishment, configuration, maintenance, and release of signaling radio bearers and data radio bearers; mobility functions; QoS management functions; UE measurement reporting and control of the reporting; detection of radio link failure (RLF) and recovery from radio link failure; and / or NAS messaging. As part of establishing an RRC connection, the RRC 216 and 226 may establish an RRC context, which may involve configuring parameters for communication between the UE 210 and the RAN.

[0106] Figure 6 is an example diagram showing the RRC state transition of the UE. The UE can Figure 1A The wireless device 106 depicted in Figure 2A and Figure 2B The UE 210 depicted in FIG. 1 and any other wireless device described in the present disclosure may be the same or similar. Figure 6 As shown in , the UE may be in at least one of three RRC states: RRC connected 602 (eg, RRC_CONNECTED), RRC idle 604 (eg, RRC_IDLE), and RRC inactive 606 (eg, RRC_INACTIVE).

[0107] In RRC connection 602, the UE has an established RRC context and may have at least one RRC connection with a base station. The base station may be similar to one of the following: Figure 1A The one or more base stations included in the RAN 104 depicted in FIG. Figure 1B One of the gNB 160 or ng-eNB 162 depicted in FIG. Figure 2A and Figure 2BgNB220 depicted in ; or any other base station described in the present disclosure. A base station connected to a 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., involving data radio bearers, signaling radio bearers, logical channels, QoS flows and / or PDU sessions); security information; and / or PHY, MAC, RLC, PDCP and / or SDAP layer configuration information. When in RRC connection 602, the mobility of the UE may be managed by the RAN (e.g., RAN 104 or NG-RAN 154). The UE may measure signal levels (e.g., reference signal levels) from a serving cell and neighboring cells, and report these measurements to the base station currently serving the UE. The UE's serving base station may request handover to a cell of one of the neighboring base stations based on the reported measurements. The RRC state may transition from RRC connected 602 to RRC idle 604 via a connection release procedure 608 , or to RRC inactive 606 via a connection deactivation procedure 610 .

[0108] In RRC idle 604, an RRC context may not be established for the UE. In RRC idle 604, the UE may not have an RRC connection with a base station. When in RRC idle 604, the UE may be in a sleep state for 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 known as cell reselection. The RRC state may transition from RRC idle 604 to RRC connected 602 through a connection establishment procedure 612, which may involve a random access procedure, as discussed in more detail below.

[0109] In RRC Inactive 606, the previously established RRC context is maintained in the UE and the base station. This allows a quick transition to RRC Connected 602 with reduced signaling overhead compared to the transition from RRC Idle 604 to RRC Connected 602. While in RRC Inactive 606, the UE may be in a sleep state, and the mobility of the UE may be managed by the UE through cell reselection. The RRC state may transition from RRC Inactive 606 to RRC Connected 602 through a Connection Resumption Procedure 614, or to RRC Idle 604 through a Connection Release Procedure 616, which may be the same or similar to the Connection Release Procedure 608.

[0110] The RRC state may be associated with a mobility management mechanism. In RRC idle 604 and RRC inactive 606, mobility is managed by the UE through cell reselection. The purpose of mobility management in RRC idle 604 and RRC inactive 606 is to allow the network to notify the UE of an event via a paging message without broadcasting the paging message over the entire mobile communication network. The mobility management mechanism used in RRC idle 604 and RRC inactive 606 may allow the network to track the UE at a cell group level, so that the paging message may be broadcast over a cell in the cell group in which the UE currently resides instead of over the entire mobile communication network. The mobility management mechanism used for RRC idle 604 and RRC inactive 606 tracks the UE at a cell group level. These mobility management mechanisms may do so using groups of different granularities. For example, there may be three levels of cell grouping granularity: a single cell; a cell within a RAN area identified by a RAN area identifier (RAI); and a cell within a group of RAN areas referred to as tracking areas and identified by a tracking area identifier (TAI).

[0111] Tracking areas may be used to track UEs at the CN level. A CN (e.g., CN 102 or 5G-CN 152) may provide a list of TAIs associated with UE registration areas to a UE. If a UE moves through cell reselection to a cell associated with a TAI that is not included in the list of TAIs associated with a UE registration area, the UE may perform a registration update with the CN to allow the CN to update the UE's location and provide the UE with a new UE registration area.

[0112] The RAN area may be used to track the UE at the RAN level. For a UE in the RRC inactive 606 state, a RAN notification area may be assigned to the UE. The RAN notification area may include one or more cell identities, a list of RAIs, or a list of TAIs. In an example, a base station may belong to one or more RAN notification areas. In an example, a cell may belong to one or more RAN notification areas. If the UE moves to a cell not included in the RAN notification area assigned to the UE through cell reselection, the UE may perform a notification area update on the RAN to update the RAN notification area of ​​the UE.

[0113] The base station storing the RRC context for the UE or the last serving base station of the UE may be referred to as the anchor base station. The anchor base station may maintain the RRC context for the UE at least during the period of time that the UE remains in the RAN notification area of ​​the anchor base station and / or during the period of time that the UE remains in RRC inactivity 606.

[0114] gNBs, such as Figure 1BThe gNB 160 in the embodiment of the present invention 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 may include RRC, PDCP, and SDAP. The gNB-DU may include RLC, MAC, and PHY.

[0115] In NR, physical signals and physical channels (about Figure 5A and Figure 5B Discussed) can be mapped onto orthogonal frequency division multiplexing (OFDM) symbols. OFDM is a multi-carrier communication scheme that transmits data through F orthogonal subcarriers (or tones). Before transmission, the data can be mapped to a series of complex symbols called source symbols (e.g., M-quadrature 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 treated as if they are in the frequency domain and used as input to the inverse fast Fourier transform (IFFT) block that transforms them into the time domain. The IFFT block can take F source symbols at a time (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 sinusoidal basis functions corresponding to the F orthogonal subcarriers. The output of the IFFT block can be F time domain samples representing the sum of the F orthogonal subcarriers. The F time domain samples can form a single OFDM symbol. After some processing (e.g., addition of a cyclic prefix) and up-conversion, the OFDM symbols 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 the 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 FFT block can be used to perform inverse processing on the OFDM symbol at the receiver to restore the data mapped to the source symbol.

[0116] Figure 7 An exemplary configuration of an NR frame into which OFDM symbols are grouped is shown. An NR frame may be identified by a system frame number (SFN). The SFN may be repeated with a period of 1024 frames. As shown, a NR frame may have a duration of 10 milliseconds (ms) and may include 10 subframes of duration 1 ms. A subframe may be divided into time slots that include, for example, 14 OFDM symbols per time slot.

[0117] The duration of a time slot may depend on the parameter set of the OFDM symbol used for the 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 mm-wave range). Parameter sets may be defined in terms of subcarrier spacing and cyclic prefix duration. For parameter sets in NR, the subcarrier spacing may be scaled up by powers of two from a baseline subcarrier spacing of 15 kHz, and the cyclic prefix duration may be scaled down by powers 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.

[0118] A slot may have a fixed number of OFDM symbols (eg, 14 OFDM symbols). Parameter sets with higher subcarrier spacing have shorter slot durations and correspondingly more slots per subframe. Figure 7 The transmission structure of the time slot duration and each subframe time slot associated with the parameter set is shown (for ease of explanation, Figure 7 Parameter sets with subcarrier spacing of 240kHz are not shown in Figure 1). Subframes in NR can be used as a time reference independent of the parameter set, while slots can be used as the unit for scheduling uplink and downlink transmissions. To support low latency, scheduling in NR can be decoupled from the slot duration and start at any OFDM symbol and continue to transmit as many symbols as needed. These partial slot transmissions can be called mini-slots or sub-slot transmissions.

[0119] Figure 8 An exemplary configuration of a time slot in the time and frequency domain of an NR carrier is shown. The time slot includes a resource element (RE) and a resource block (RB). RE is the smallest physical resource in NR. RE spans one OFDM symbol in the time domain through one subcarrier in the frequency domain, such as Figure 8 As shown in Figure 1. RB spans twelve consecutive REs in the frequency domain, as Figure 8 As shown. The NR carrier can be limited to a width of 275RB or 275×12=3300 subcarriers. If this restriction is used, the NR carrier can be limited to 50MHz, 100MHz, 200MHz and 400MHz for subcarrier spacings of 15kHz, 30kHz, 60kHz and 120kHz, respectively, where the 400MHz bandwidth can be set based on the 400MHz bandwidth limit per carrier.

[0120] Figure 8A single parameter set is shown used across the entire bandwidth of the NR carrier. In other example configurations, multiple parameter sets may be supported on the same carrier.

[0121] NR may support wide carrier bandwidths (e.g., up to 400 MHz for a subcarrier spacing of 120 kHz). Not all UEs may be able to receive the full carrier bandwidth (e.g., due to hardware limitations). Moreover, receiving the full carrier bandwidth may be prohibitive in terms of UE power consumption. In an example, to reduce power consumption and / or for other purposes, the UE may adapt the size of the UE's receive bandwidth based on the amount of traffic the UE plans to receive. This is referred to as bandwidth adaptation.

[0122] NR defines bandwidth parts (BWPs) to support UEs that cannot receive the full carrier bandwidth and supports bandwidth adaptation. In an example, a BWP may be defined by a subset of contiguous RBs on a carrier. The UE may 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 for the serving cell may be active. The one or more BWPs may be referred to as the active BWP of the serving cell. When a serving cell is configured with a secondary uplink carrier, the serving cell may have one or more first active BWPs in the uplink carrier and one or more second active BWPs in the secondary uplink carrier.

[0123] For unpaired spectrum, a downlink BWP from a set of configured downlink BWPs may be linked with an uplink BWP from a set of configured uplink BWPs if the downlink BWP index of the downlink BWP is the same as the uplink BWP index of the uplink BWP. For unpaired spectrum, the UE may expect the center frequency of the downlink BWP to be the same as the center frequency of the uplink BWP.

[0124] For a downlink BWP in a set of configured downlink BWPs on a primary cell (PCell), the base station may configure a UE with one or more control resource sets (CORESETs) for at least one search space. A search space is a set of locations in the time and frequency domain where a UE can look for control information. A search space may be a UE-specific search space or a common search space (potentially usable by multiple UEs). For example, a base station may configure a common search space for a UE on a PCell or a primary secondary cell (PSCell) in an active downlink BWP.

[0125] For an uplink BWP in the set of configured uplink BWPs, the BS may configure one or more resource sets for one or more PUCCH transmissions for the UE. The UE may receive downlink receptions (e.g., PDCCH or PDSCH) in the downlink BWP according to the configured parameter set (e.g., subcarrier spacing and cyclic prefix duration) for the downlink BWP. The UE may transmit uplink transmissions (e.g., PUCCH or PUSCH) in the uplink BWP according to the configured parameter set (e.g., subcarrier spacing and cyclic prefix length of the uplink BWP).

[0126] One or more BWP indicator fields may be provided in downlink control information (DCI). The value of the BWP indicator field may indicate which BWP in a 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.

[0127] 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 to 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.

[0128] The base station may configure the BWP inactivity timer value for the PCell for the UE. 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 in the following circumstances: (a) when the UE detects a DCI indicating an active downlink BWP other than the default downlink BWP for paired spectrum operation; or (b) when the UE detects a DCI indicating an active downlink BWP or an active uplink BWP other than the default downlink BWP or uplink BWP for unpaired spectrum operation. If the UE does not detect the 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., an increment from zero to the BWP inactivity timer value, or a decrement from the BWP inactivity timer value to zero). When the BWP inactivity timer expires, the UE may switch from the active downlink BWP to the default downlink BWP.

[0129] In an example, the base station may semi-statically configure the UE with one or more BWPs. The UE may switch the active BWP from the first BWP to the second BWP in response to receiving a DCI indicating that the second BWP is the active BWP and / or in response to expiration of a BWP inactivity timer (e.g., when the second BWP is the default BWP).

[0130] Downlink and uplink BWP switching can be performed independently in paired spectrum (where BWP switching refers to switching from a currently active BWP to a non-currently active BWP). In unpaired spectrum, downlink and uplink BWP switching can be performed simultaneously. Switching between configured BWPs can occur based on RRC signaling, DCI, expiration of a BWP inactivity timer, and / or initiation of random access.

[0131] Fig. 9 An example of bandwidth adaptation using three configured BWPs of an NR carrier is shown. A UE configured with the three BWPs can switch from one BWP to another at a switching point. Fig. 9 In 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 BWPs at a switching point. Fig. 9 904. In the example of , the UE may switch from BWP 902 to BWP 904 at switch point 908. The switch at switch point 908 may occur for any suitable reason, such as in response to expiration of a BWP inactivity timer (indicating a switch to a default BWP) and / or in response to receiving a DCI indicating that BWP 904 is an active BWP. The UE may switch from active BWP 904 to BWP 906 at switch point 910 in response to receiving a DCI indicating that BWP 906 is an active BWP. The UE may switch from active BWP 906 to BWP 904 at switch point 912 in response to expiration of a BWP inactivity timer and / or in response to receiving a DCI indicating that BWP 904 is an active BWP. The UE may switch from active BWP 904 to BWP 902 at switch point 914 in response to receiving a DCI indicating that BWP 902 is an active BWP.

[0132] If the UE is configured for a secondary cell with a default downlink BWP and timer values ​​from the 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 the timer values ​​and default downlink BWP for the secondary cell in the same / similar manner as the UE would use these values ​​for the primary cell.

[0133] To provide higher data rates, two or more carriers may be aggregated and transmitted to / from the same UE simultaneously using carrier aggregation (CA). The aggregated carriers in CA may be referred to as component carriers (CC). When CA is used, there are many serving cells for the UE, one serving cell per CC. CCs may have three configurations in the frequency domain.

[0134] Fig. 10A Three CA configurations with two CCs are shown. In the intra-band contiguous configuration 1002, the two CCs are aggregated in the same frequency band (Band A) and are located directly adjacent to each other in the frequency band. In the intra-band non-contiguous configuration 1004, the two CCs are aggregated in the same frequency band (Band A) and are separated by a gap in the frequency band. In the inter-band configuration 1006, the two CCs are located in the frequency bands (Band A and Band B).

[0135] In an example, up to 32 CCs may be aggregated. Aggregated CCs may have the same or different bandwidths, subcarrier spacings, and / or duplex schemes (TDD or FDD). A serving cell for a UE using CA may have a downlink CC. For FDD, one or more uplink CCs may optionally be configured for the serving cell. For example, the ability to aggregate more downlink carriers than uplink carriers may be useful when the UE has more data traffic in the downlink than in the uplink.

[0136] When CA is used, one of the aggregated cells for the UE may be referred to as a primary cell (PCell). The PCell may be a serving cell to which the UE initially connects at RRC connection establishment, reestablishment and / or handover. The PCell may provide NAS mobility information and security input to the UE. The UE may have different PCells. In the downlink, the carrier corresponding to the PCell may be referred to as a downlink primary CC (DL PCC). In the uplink, the carrier corresponding to the PCell may be referred to as an uplink primary CC (UL PCC). Other aggregated cells for the UE may be referred to as secondary cells (SCells). In an example, the SCell may be configured after the PCell is configured for the UE. For example, the SCell may be configured via an RRC connection reconfiguration procedure. In the downlink, the carrier corresponding to the SCell may be referred to as a downlink secondary CC (DL SCC). In the uplink, the carrier corresponding to the SCell may be referred to as an uplink secondary CC (UL SCC).

[0137] The configured SCell for a UE can be activated and deactivated based on, for example, traffic and channel conditions. Deactivation of an SCell can mean stopping PDCCH and PDSCH reception on the SCell, and stopping PUSCH, SRS, and CQI transmission on the SCell. Figure 4B The MAC CE may be used to activate and deactivate the configured SCells. For example, the MAC CE may use a bitmap (e.g., one bit per SCell) to indicate which SCells (e.g., in a subset of configured SCells) are activated or deactivated for the UE. The configured SCells may be deactivated in response to the expiration of an SCell deactivation timer (e.g., one SCell deactivation timer per SCell).

[0138] The downlink control information of a cell (such as scheduling assignments and scheduling grants) 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. Uplink control information for aggregated cells (e.g., HARQ confirmation 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. The cell can be divided into multiple PUCCH groups.

[0139] Fig. 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 may include one or more downlink CCs, respectively. Fig. 10B, PUCCH group 1010 includes three downlink CCs: PCell 1011, SCell 1012, and SCell 1013. PUCCH group 1050 includes three downlink CCs: PCell 1051, SCell 1052, and SCell 1053 in this example. One or more uplink CCs may be configured as PCell 1021, SCell 1022, and SCell 1023. One or more other uplink CCs may be configured as primary Scell ​​(PSCell) 1061, SCell 1062, and SCell 1063. Uplink control information (UCI) related to the downlink CCs of PUCCH group 1010 (shown as UCI 1031, UCI 1032, and UCI 1033) may be transmitted in the uplink of PCell 1021. Uplink control information (UCI) related to the downlink CCs of PUCCH group 1050 (shown as UCI 1071, UCI 1072, and UCI 1073) may be transmitted in the uplink of PSCell 1061. In the example, if Fig. 10B If the aggregated cell depicted in FIG. 1 is not divided into PUCCH group 1010 and PUCCH group 1050 , a single uplink PCell transmits UCI associated with a downlink CC, and the PCell may become overloaded. By dividing the transmission of UCI between PCell 1021 and PSCell 1061 , overload can be prevented.

[0140] A physical cell ID and a cell index may be assigned to a cell comprising a downlink carrier and an optional uplink carrier. The physical cell ID or cell index may identify a downlink carrier and / or an uplink carrier of a cell, for example, depending on the context in which the physical cell ID is used. The physical cell ID may be determined using a synchronization signal transmitted on a downlink component carrier. The cell index may be determined using an RRC message. In the present disclosure, the physical cell ID may be referred to as a carrier ID, and the cell index may be referred to as a carrier index. For example, when the present disclosure relates to a first physical cell ID of a first downlink carrier, the present disclosure may mean that the first physical cell ID is used for a cell comprising the first downlink carrier. The same / similar concepts may apply, for example, to carrier activation. When the present disclosure indicates that a first carrier is activated, the present specification may mean that a cell comprising the first carrier is activated.

[0141] 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. A transport block can be generated based on the assignment / grant of each serving cell. A transport block and potential HARQ retransmissions of the transport block can be mapped to a serving cell.

[0142] In the downlink, the base station may transmit (e.g., unicast, multicast and / or broadcast) one or more reference signals (RS) to the UE (e.g., PSS, SSS, CSI-RS, DMRS and / or PT-RS, such as Figure 5A In the uplink, the UE may transmit one or more RSs to the base station (e.g., DMRS, PT-RS, and / or SRS, as shown in FIG. Figure 5B ). The PSS and SSS may be transmitted by a base station and used by a UE to synchronize the UE with the base station. The PSS and SSS may be provided in a synchronization signal (SS) / physical broadcast channel (PBCH) block that includes the PSS, SSS, and PBCH. The base station may periodically transmit bursts of SS / PBCH blocks.

[0143] Fig.11A An example of the structure and location of SS / PBCH blocks is shown. A burst of SS / PBCH blocks may include one or more SS / PBCH blocks (e.g., 4 SS / PBCH blocks, such as Fig.11A As shown). Bursts may be transmitted periodically (e.g., every 2 frames or 20 ms). Bursts may be limited to half a frame (e.g., the first half frame with a duration of 5 ms). It should be understood that Fig.11A are examples, and these parameters (number of SS / PBCH blocks per burst, periodicity of bursts, burst position within a frame) may be configured based on, for example: the carrier frequency of the cell in which the SS / PBCH blocks are transmitted; a parameter set or subcarrier spacing for the cell; configuration by the network (e.g., using RRC signaling); or any other suitable factor. In an example, the UE may assume the subcarrier spacing of the SS / PBCH blocks based on the carrier frequency being monitored unless the radio network configures the UE to assume a different subcarrier spacing.

[0144] The SS / PBCH block may span one or more OFDM symbols in the time domain (e.g., 4 OFDM symbols, such as Fig.11A ) and may span one or more subcarriers in the frequency domain (e.g., 240 consecutive subcarriers). The PSS, SSS, and PBCH may have a common center frequency. The PSS may be transmitted first and may span, for example, 1 OFDM symbol and 127 subcarriers. The SSS may be transmitted after the PSS (e.g., two symbols later) and may span 1 OFDM symbol and 127 subcarriers. The PBCH may be transmitted after the PSS (e.g., spanning the next 3 OFDM symbols) and may span 240 subcarriers.

[0145] The UE may not know the location of the SS / PBCH blocks in the time and frequency domains (for example, when the UE is searching for cells). In order to find and select a cell, the UE may monitor the carrier of the PSS. For example, the UE may monitor the frequency position within the carrier. If the PSS is not found after a certain duration (for example, 20ms), the UE may 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 and frequency domains, the UE may determine the location of the SSS and PBCH based on the known structure of the SS / PBCH block, respectively. The SS / PBCH block may be a cell definition SS block (CD-SSB). In an example, a primary cell may be associated with a CD-SSB. The CD-SSB may be located on a synchronization raster. In an example, cell selection / search and / or reselection may be based on the CD-SSB.

[0146] The SS / PBCH block may be used by the UE to determine one or more parameters of the cell. For example, the UE may determine the physical cell identifier (PCI) of the cell based on the sequence of the PSS and SSS, respectively. The UE may determine the location of the frame boundary of the cell based on the location of the SS / PBCH block. For example, the SS / PBCH block may indicate that it has been transmitted according to a transmission pattern in which the SS / PBCH block in the transmission pattern is a known distance from the frame boundary.

[0147] The PBCH may use QPSK modulation and may use forward error correction (FEC). FEC may use polarity coding. One or more symbols spanned by the PBCH may carry one or more DMRS for demodulating the PBCH. The PBCH may include an indication of the current system frame number (SFN) of the cell and / or an SS / PBCH block timing index. These parameters may contribute to the time synchronization of the UE with the base station. The PBCH may include a master information block (MIB) for providing one or more parameters to the UE. The MIB may be used by the UE to locate the remaining minimum system information (RMSI) associated with the cell. The RMSI may include a system information block type 1 (SIB1). SIB1 may contain information required for the UE to access the cell. The UE may use one or more parameters of the MIB to monitor the PDCCH that may be used to schedule the PDSCH. The PDSCH may include SIB1. SIB1 may be decoded using the parameters provided in the MIB. The PBCH may indicate that SIB1 does not exist. Based on the PBCH indicating that SIB1 does not exist, the UE may point to a frequency. The UE may search for SS / PBCH blocks at the frequency to which the UE is pointing.

[0148] The UE may 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 may not assume QCL for SS / PBCH block transmissions with different SS / PBCH block indices.

[0149] SS / PBCH blocks (e.g., those within a half-frame) may be transmitted in spatial directions (e.g., using different beams across the coverage area of ​​a cell). In an example, a first SS / PBCH block may be transmitted in a first spatial direction using a first beam, and a second SS / PBCH block may be transmitted in a second spatial direction using a second beam.

[0150] In an example, within a frequency range of a carrier, a base station may transmit multiple SS / PBCH blocks. In an example, a first PCI of a first SS / PBCH block of the multiple SS / PBCH blocks may be different from a second PCI of a second SS / PBCH block of the multiple SS / PBCH blocks. PCIs of SS / PBCH blocks transmitted in different frequency positions may be different or the same.

[0151] The CSI-RS may be transmitted by a base station and used by a UE to obtain channel state information (CSI). The base station may configure the UE with one or more CSI-RS for channel estimation or any other suitable purpose. The base station may configure the UE with one or more CSI-RSs of the same / similar CSI-RS. The UE may measure the one or more CSI-RSs. The UE may 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 may provide the CSI report to the base station. The base station may use the feedback provided by the UE (e.g., the estimated downlink channel state) to perform link adaptation.

[0152] The base station may semi-statically configure the UE with one or more CSI-RS resource sets. The CSI-RS resources may be associated with positions and periodicity in the time and frequency domains. The base station may selectively activate and / or deactivate CSI-RS resources. The base station may indicate to the UE that the CSI-RS resources in the CSI-RS resource set are activated and / or deactivated.

[0153] 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 reporting, the UE can be configured with the timing and / or period of multiple CSI reports. For aperiodic CSI reporting, 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 value. For semi-persistent CSI reporting, the base station can configure the UE to transmit periodically and selectively activate or deactivate periodic reporting. The base station can configure the UE with a CSI-RS resource set and CSI reporting using RRC signaling.

[0154] The CSI-RS configuration may include one or more parameters indicating, for example, up to 32 antenna ports. The UE may be configured to employ the same OFDM symbol for downlink CSI-RS and control resource set (CORESET) when the downlink CSI-RS and CORESET are spatially QCLed and the resource elements associated with the downlink CSI-RS are outside the physical resource blocks (PRBs) configured for the CORESET. The UE may be configured to employ the same OFDM symbol for downlink CSI-RS and SS / PBCH blocks when the downlink CSI-RS and SS / PBCH blocks are spatially QCLed and the resource elements associated with the downlink CSI-RS are outside the PRBs configured for the SS / PBCH blocks.

[0155] 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 consistent demodulation of one or more downlink physical channels (e.g., PDSCH). The NR network can support one or more variable and / or configurable DMRS modes for data demodulation. At least one downlink DMRS configuration can support a frontload DMRS mode. The frontload 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., maximum number) of frontload DMRS symbols for 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, in which the DMRS position, DMRS pattern and / or scrambling sequence can be the same or different. The base station may use the same precoding matrix to transmit the downlink DMRS and the corresponding PDSCH. The UE may use the one or more downlink DMRS to perform consistent demodulation / channel estimation on the PDSCH.

[0156] In an example, a transmitter (e.g., a base station) may use a precoder matrix for a portion of a transmission bandwidth. For example, a transmitter may use a first precoder matrix for a first bandwidth and a second precoder matrix for a second bandwidth. The first precoder matrix and the second precoder matrix may be different based on the first bandwidth being different from the second bandwidth. The UE may assume that the same precoding matrix is ​​used throughout a set of PRBs. The set of PRBs may be represented as a precoding resource block group (PRG).

[0157] The PDSCH may include one or more layers. The UE may assume that at least one symbol with DMRS is present on a layer in the one or more layers of the PDSCH. The higher layers may configure up to 3 DMRS for the PDSCH.

[0158] The downlink PT-RS may be transmitted by a base station and used by a UE for phase noise compensation. Whether a downlink PT-RS exists may depend on an RRC configuration. The presence and / or type of a downlink PT-RS may be configured based on a UE-specific configuration using a combination of RRC signaling and / or an association with one or more parameters for other purposes (e.g., a modulation and coding scheme (MCS)) that may be indicated by a DCI. When configured, the dynamic presence of a downlink PT-RS may be associated with one or more DCI parameters including at least an MCS. The NR network may support multiple PT-RS densities defined in the time / frequency domain. When present, the frequency domain density may be associated with at least one configuration of the scheduled bandwidth. The UE may use 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. The downlink PT-RS may be limited to the scheduled time / frequency duration of the UE. The downlink PT-RS may be transmitted on a symbol to facilitate phase tracking at the receiver.

[0159] The UE may transmit an uplink DMRS to a base station for channel estimation. For example, the base station may use the uplink DMRS to consistently demodulate one or more uplink physical channels. For example, the UE may transmit an uplink DMRS with a PUSCH and / or a PUCCH. The uplink DM-RS may span a frequency range similar to the frequency range associated with the corresponding physical channel. The base station may configure the UE with one or more uplink DMRS configurations. At least one DMRS configuration may support a front-loaded DMRS mode. The front-loaded DMRS may be mapped on one or more OFDM symbols (e.g., one or two adjacent OFDM symbols). One or more uplink DMRS may be configured to be transmitted at one or more symbols of the PUSCH and / or PUCCH. The base station may semi-statically configure the UE with the number (e.g., maximum number) of front-loaded DMRS symbols for the PUSCH and / or PUCCH, and the UE may use the front-loaded DMRS symbol to schedule single-symbol DMRS and / or dual-symbol DMRS. NR networks may support a common DMRS structure for downlink and uplink (e.g., for cyclic prefix orthogonal frequency division multiplexing (CP-OFDM)), where the DMRS positions, DMRS patterns, and / or scrambling sequences of the DMRS may be the same or different.

[0160] The PUSCH may include one or more layers, and the UE may transmit at least one symbol having a DMRS present on a layer in the one or more layers of the PUSCH. In an example, a higher layer may configure up to three DMRSs for the PUSCH.

[0161] Depending on the RRC configuration of the UE, an uplink PT-RS (which can be used by the base station for phase tracking and / or phase noise compensation) may or may not exist. The presence and / or type of the uplink PT-RS can be configured based on UE-specific configuration through a combination of RRC signaling and / or one or more parameters for other purposes (e.g., modulation and coding scheme (MCS)) indicated by the DCI. When configured, the dynamic presence of the uplink PT-RS can be associated with one or more DCI parameters including at least the MCS. The radio network can support multiple uplink PT-RS densities defined in the time / frequency domain. When present, the frequency domain density can be associated with at least one configuration of the scheduled bandwidth. The UE can use the same precoding for DMRS ports and PT-RS ports. The number of PT-RS ports can be less than the number of DMRS ports in the scheduled resources. For example, the uplink PT-RS can be limited to the scheduled time / frequency duration of the UE.

[0162] The UE may transmit an SRS to a 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 semi-statically configure the UE with one or more SRS resource sets. For an SRS resource set, the base station may configure the UE with one or more SRS resources. The applicability of the SRS resource set may be configured by a higher layer (e.g., RRC) parameter. For example, when a higher layer parameter indicates beam management, the SRS resources in the SRS resource set 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 time (e.g., at the same time). 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, wherein 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 used for the UE to select at least one configured SRS resource set from one or more configured SRS resource sets. SRS trigger type 0 may refer to SRS triggered based on higher layer signaling. SRS trigger type 1 may refer to SRS triggered based on one or more DCI formats. In an example, when PUSCH and SRS are transmitted in the same time slot, the UE may be configured to transmit SRS after transmission of PUSCH and corresponding uplink DMRS.

[0163] The base station can semi-statically configure the UE using one or more SRS configuration parameters indicating at least one of the following: an SRS resource configuration identifier; the number of SRS ports; the time domain behavior of the SRS resource configuration (e.g., an indication of periodic, semi-persistent, or non-periodic SRS); time slot, mini-slot, and / or subframe level periodicity; time slots of periodic and / or non-periodic SRS resources; the number of OFDM symbols in the SRS resources; the start OFDM symbol of the SRS resources; SRS bandwidth; frequency hopping bandwidth; cyclic shift; and / or SRS sequence ID.

[0164] The antenna ports are defined such that the channel through which a symbol on the antenna port is communicated can be inferred from the channel through which another symbol on the same antenna port is communicated. If a first symbol and a second symbol are transmitted on the same antenna port, the receiver can infer the channel (e.g., fading gain, multipath delay, etc.) used to communicate the second symbol on the antenna port from the channel used to communicate the first symbol on the antenna port. If one or more large-scale properties of the channel through which the first symbol on the first antenna port is communicated can be inferred from the channel through which the second symbol on the second antenna port is communicated, 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.

[0165] 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 beamforming reference signals. The UE may perform downlink beam measurements and generate beam measurement reports based on downlink reference signals (e.g., channel state information reference signals (CSI-RS)). After setting up an RRC connection with a base station, the UE may perform a downlink beam measurement procedure.

[0166] Fig. 11B An example of a channel state information reference signal (CSI-RS) mapped in the time and frequency domain is shown. Fig. 11BThe squares shown in the figure may represent resource blocks (RBs) within the bandwidth of the cell. The base station may transmit one or more RRC messages including CSI-RS resource configuration parameters indicating one or more CSI-RS. One or more of the following parameters may be configured for the CSI-RS resource configuration through 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., symbol 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 parameters, CSI-RS sequence parameters, code division multiplexing (CDM) type parameters, frequency density, transmission comb, quasi co-location (QCL) parameters (e.g., QCL-scramblingidentity, crs-portscount, mbsfn-subframeconfiglist, csi-rs-configZPid, qcl-csi-rs-configNZPid) and / or other radio resource parameters.

[0167] Fig. 11B The three beams shown may be configured for a UE in a UE-specific configuration. Fig. 11B Three beams (beam #1, beam #2, and beam #3) are illustrated in FIG. 1 , and more or fewer beams may be configured. CSI-RS 1101 may be allocated to beam #1, which may be transmitted in one or more subcarriers in the RB of the first symbol. CSI-RS 1102 may be allocated to beam #2, which may be transmitted in one or more subcarriers in the RB of the second symbol. CSI-RS 1103 may be allocated 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), a base station may use other subcarriers in the same RB (e.g., those subcarriers not used to transmit CSI-RS 1101) to transmit another CSI-RS associated with a beam of another UE. By using time domain multiplexing (TDM), a beam for a UE may be configured so that the beam for the UE uses symbols from beams of other UEs.

[0168] CSI-RS, such as Fig. 11BThose shown in (e.g., CSI-RS 1101, 1102, 1103) may be transmitted by a base station and used by a UE for one or more measurement values. For example, a UE may measure a reference signal received power (RSRP) of a configured CSI-RS resource. The base station may configure the UE with a reporting configuration, and the UE may report the RSRP measurement value to the network (e.g., via one or more base stations) based on the reporting configuration. In the example, the base station may determine one or more transmission configuration indication (TCI) states including multiple reference signals based on the reported measurement results. In the example, the base station may indicate one or more TCI states to the UE (e.g., via RRC signaling, MAC CE, and / or DCI). The UE may receive a downlink transmission having a receive (Rx) beam determined based on the one or more TCI states. In the example, the UE may or may not have beam correspondence capability. If the UE has beam correspondence capability, the UE may determine the spatial domain filter of the transmit (Tx) beam based on the spatial domain filter of the corresponding Rx beam. If the UE does not have beam-corresponding capability, the UE may perform an uplink beam selection procedure to determine the spatial domain filter of the Tx beam. The UE may perform an uplink beam selection procedure based on one or more sounding reference signal (SRS) resources configured to the UE by the base station. The base station may select and indicate the uplink beam of the UE based on measurements of one or more SRS resources transmitted by the UE.

[0169] In the beam management procedure, the UE may assess (e.g., measure) the channel quality of one or more beam pair links, beam pair links including a transmit beam transmitted by a base station, and a receive beam received by the UE. Based on the assessment, the UE may transmit a beam measurement report indicating one or more beam pair quality parameters, 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).

[0170] Fig. 12AExamples of three downlink beam management procedures are shown: P1, P2, and P3. Procedure P1 can enable UE measurements of transmit (Tx) beams of a transmit reception point (TRP) (or multiple TRPs), for example to support selection of one or more base station Tx beams and / or UE Rx beams (shown as ovals 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 ovals rotating in a counterclockwise direction indicated by dashed arrows in the top rows of P1 and P2). Beamforming at the UE can include Rx beam sweeping for a set of beams (shown as ovals rotating in a clockwise direction indicated by dashed arrows in the bottom rows of P1 and P3). Procedure P2 can be used to enable UE measurements of Tx beams of a TRP (shown as ovals rotating in a counterclockwise direction indicated by dashed arrows in the top row of P2). The UE and / or the base station may perform procedure P2 using a smaller beam set than the beam set used in procedure P1, or using a narrower beam than the beam used in procedure P1. This may be referred to as beam refinement. The UE may perform procedure P3 for Rx beam determination by using the same Tx beam at the base station and sweeping the Rx beam at the UE.

[0171] Fig. 12B Examples of three uplink beam management procedures are shown: U1, U2, and U3. Procedure U1 can be used to enable a base station to perform measurements on a UE's Tx beams, for example, to support selection of one or more UE Tx beams and / or base station Rx beams (shown as ovals 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 ovals rotating in a clockwise direction indicated by dashed arrows 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 ovals rotating in a counterclockwise direction indicated by dashed arrows in the top rows of U1 and U2). Procedure U2 can be used to enable a base station to adjust its Rx beam when the UE uses a fixed Tx beam. The UE and / or base station can perform procedure U2 using a smaller beam set than the beam set used in procedure P1, or using a narrower beam than the beam used in procedure P1. This may be referred to as beam refinement. The UE may perform procedure U3 to adjust its Tx beam when the base station uses a fixed Rx beam.

[0172] 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., 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 unsatisfactory (e.g., having an error rate above an error rate threshold, a received signal power below a received signal power threshold, expiration of a timer, etc.).

[0173] The UE may measure the quality of a beam-to-link using one or more reference signals (RS), 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 (DMRS). The quality of a beam-to-link may be based on one or more of the following: a block error rate (BLER), an RSRP value, a signal-to-interference-plus-noise ratio (SINR) value, a reference signal received quality (RSRQ) value, and / or a CSI value measured on an RS resource. The base station may indicate that the RS resource is quasi-co-located (QCLed) with one or more DM-RS of a channel (e.g., a control channel, a shared data channel, etc.). When the channel characteristics (e.g., Doppler shift, Doppler spread, average delay, delay spread, spatial Rx parameters, fading, etc.) from a transmission to the UE via the RS resource are similar or identical to the channel characteristics from a transmission to the UE via the channel, the RS resource and the one or more DMRS of the channel may be QCLed.

[0174] The network (e.g., gNB and / or ng-eNB of the network) and / or the UE may initiate a random access procedure. A UE in RRC_IDLE state and / or RRC_INACTIVE state may initiate a random access procedure to request a 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 there are no available PUCCH resources) and / or to 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.

[0175] Fig.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. Fig.13AThe procedure 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).

[0176] The configuration message 1310 may be transmitted, for example, using one or more RRC messages. The one or more RRC messages may indicate one or more random access channel (RACH) parameters to the UE. The one or more RACH parameters may 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.

[0177] The one or more RACH parameters provided in the configuration message 1310 may indicate one or more physical RACH (PRACH) opportunities that can be used to transmit 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 an association between: (a) one or more PRACH opportunities, and (b) one or more reference signals. The one or more RACH parameters may indicate an association between: (a) one or more preambles, and (b) one or more reference signals. The one or more reference signals may be SS / PBCH blocks and / or CSI-RS. For example, the one or more RACH parameters may indicate the number of SS / PBCH blocks mapped to the PRACH opportunity and / or the number of preambles mapped to the SS / PBCH block.

[0178] The one or more RACH parameters provided in the configuration message 1310 may be used to determine the uplink transmission power of Msg 1 1311 and / or Msg3 1313. For example, the one or more RACH parameters may indicate a reference power for preamble transmission (e.g., a received target power and / or an initial power for preamble transmission). There may be one or more power offsets indicated by the one or more RACH parameters. For example, the one or more RACH parameters may indicate: a power ramp step size; a power offset between SSB and CSI-RS; a power offset between transmissions of Msg 1 1311 and Msg 3 1313; and / or a power offset value between preamble groups. The one or more RACH parameters may indicate one or more thresholds based on which the UE may determine at least one reference signal (e.g., SSB and / or CSI-RS) and / or uplink carrier (e.g., a normal uplink (NUL) carrier and / or a supplementary uplink (SUL) carrier).

[0179] Msg 1 1311 may include one or more preamble transmissions (e.g., a preamble transmission and one or more preamble retransmissions). The RRC message may be used to configure one or more preamble groups (e.g., group A and / or group B). The preamble group may include one or more preambles. The UE may determine the preamble group based on the path loss measurement value and / or the size of Msg 3 1313. The UE may measure the RSRP of one or more reference signals (e.g., SSB and / or CSI-RS) and determine at least one reference signal having an RSRP above an RSRP threshold (e.g., rsrp-ThresholdSSB and / or rsrp-ThresholdCSI-RS). For example, if the association between the one or more preambles and the at least one reference signal is configured by an RRC message, the UE may select at least one preamble associated with the one or more reference signals and / or the selected preamble group.

[0180] The UE may determine the preamble based on the one or more RACH parameters provided in the configuration message 1310. For example, the UE may determine the preamble based on a path loss measurement, an RSRP measurement, and / or the size of Msg 3 1313. As another example, the one or more RACH parameters may indicate: a preamble format; a maximum number of preamble transmissions; and / or one or more thresholds for determining one or more preamble groups (e.g., group A and group B). The base station may 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 the association is configured, the UE may determine the preamble included in Msg 1 1311 based on the association. Msg 1 1311 may be transmitted to the base station via one or more PRACH opportunities. The UE may use one or more reference signals (e.g., SSB and / or CSI-RS) for selecting a preamble and for determining a PRACH opportunity. One or more RACH parameters (eg, ra-ssb-OccasionMskIndex and / or ra-OccasionList) may indicate an association between a PRACH opportunity and the one or more reference signals.

[0181] If no response is received after the preamble transmission, the UE may perform a preamble retransmission. The UE may increase the uplink transmission power for the preamble retransmission. The UE may select the initial preamble transmission power based on the path loss measurement and / or the target received preamble power configured by the network. The UE may determine to retransmit the preamble and may ramp up the uplink transmission power. The UE may receive one or more RACH parameters (e.g., PREAMBLE_POWER_RAMPING_STEP) indicating the ramp-up step size for the preamble retransmission. The ramp-up step size may be the amount of incremental increase in the uplink transmission power for retransmission. If the UE determines the same reference signal (e.g., SSB and / or CSI-RS) as the previous preamble transmission, the UE may ramp up the uplink transmission power. The UE may count the number of preamble transmissions and / or retransmissions (e.g., PREAMBLE_TRANSMISSION_COUNTER). For example, if the number of preamble transmissions exceeds a threshold (eg, preambleTransMax) configured by the one or more RACH parameters, the UE may determine that the random access procedure was not successfully completed.

[0182] Msg 2 1312 received by the UE may include a RAR. In some scenarios, Msg 2 1312 may include multiple RARs corresponding to multiple UEs. Msg 2 1312 may be received after or in response to the transmission of Msg 1 1311. Msg 2 1312 may be scheduled on the DL-SCH and indicated on the PDCCH using a random access RNTI (RA-RNTI). Msg 2 1312 may indicate that Msg 1 1311 is received by the base station. Msg 2 1312 may include a time alignment command that may be used by the UE to adjust the transmission timing of the UE, 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 opportunity 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 opportunity starting from the end of the preamble transmission). The one or more symbols may be determined based on a parameter set. The PDCCH may be in a common search space (e.g., Type1-PDCCH common search space) configured by an RRC message. 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 a random access procedure. The UE may use a random access RNTI (RA-RNTI). The RA-RNTI may be associated with the PRACH opportunity in which the UE transmits the preamble. For example, the UE may determine the RA-RNTI based on: an OFDM symbol index; a time slot index; a frequency domain index; and / or a UL carrier indicator of a PRACH opportunity. Examples of RA-RNTIs may be as follows:

[0183] RA-RNTI=1+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id

[0184] Where s_id may be the index of the first OFDM symbol of the PRACH opportunity (e.g., 0≤s_id<14), t_id may be the index of the first time slot of the PRACH opportunity in the system frame (e.g., 0≤t_id<80), f_id may be the index of the PRACH opportunity 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 a NUL carrier and 1 for a SUL carrier).

[0185] The UE may transmit Msg3 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 example, Fig.13A Contention resolution in a contention-based random access procedure as shown in . In some scenarios, multiple UEs may transmit the same preamble to a base station, and the base station may provide a RAR corresponding to the UE. If the multiple UEs interpret the RAR as corresponding to themselves, a conflict may occur. Contention resolution (e.g., using Msg 3 1313 and Msg 4 1314) may be used to increase the likelihood that a UE does not mistakenly use the identity of another UE. To perform contention resolution, the UE may include a device identifier in Msg 3 1313 (e.g., if a C-RNTI is assigned, the TC-RNTI included in Msg2 1312 and / or any other suitable identifier).

[0186] 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 3 1313, the base station will address the UE on the PDCCH using the C-RNTI. If a unique C-RNTI of the UE is detected on the PDCCH, it is determined that the random access procedure is successfully completed. If a TC-RNTI is included in Msg 3 1313 (e.g., if the UE is in an RRC_IDLE state or is 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 is successfully completed.

[0187] The UE may be configured with a supplementary uplink (SUL) carrier and a normal uplink (NUL) carrier. Initial access (e.g., a random access procedure) may be supported in an uplink carrier. For example, a base station may configure two separate RACH configurations for a UE: one for a SUL carrier and the other for a NUL carrier. For random access in a cell configured with a SUL carrier, the network may 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 may determine the SUL carrier. The uplink transmission (e.g., Msg 1 1311 and / or Msg 3 1313) of the random access procedure may remain on the selected carrier. In one or more cases, the UE may switch uplink carriers during the random access procedure (e.g., between Msg 1 1311 and Msg 3 1313). For example, the UE may determine and / or switch an uplink carrier for Msg 1 1311 and / or Msg 3 1313 based on channel clarity assessment (eg, listen before talk).

[0188] Fig. 13B The two-step contention-free random access procedure is shown. Fig.13A Similar to the four-step contention-based random access procedure shown, the base station may transmit a configuration message 1320 to the UE before the procedure is initiated. The configuration message 1320 may be similar to the configuration message 1310 in some aspects. Fig. 13B The procedure shown includes the transmission of two messages: Msg 1 1321 and Msg 2 1322. Msg 1 1321 and Msg 2 1322 may be similar in some respects to Fig.13A As shown in Msg 1 1311 and Msg 2 1312. Fig.13A and Fig. 13B It will be appreciated that the contention-free random access procedure may not include messages similar to Msg 3 1313 and / or Msg 4 1314 .

[0189] Can be initiated for beam failure recovery, other SI requests, SCell addition and / or handover Fig. 13B For example, the base station may indicate or assign a preamble to be used for Msg 1 1321 to the UE. The UE may receive an indication of the preamble (eg, ra-PreambleIndex) from the base station via PDCCH and / or RRC.

[0190] After transmitting the preamble, the UE may start a time window (e.g., ra-ResponseWindow) to monitor the PDCCH for 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 the RRC message (e.g., recoverySearchSpaceId). The UE may monitor PDCCH transmissions addressed to the Cell RNTI (C-RNTI) on the search space. Fig. 13B In the contention-free random access procedure shown, the UE may determine that the random access procedure is successfully completed after or in response to the transmission of Msg 1 1321 and the reception of the corresponding Msg 2 1322. For example, if the PDCCH transmission is addressed to the C-RNTI, the UE may determine that the random access procedure is successfully completed. For example, if the UE receives a RAR including a preamble identifier corresponding to a 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 a confirmation of the SI request.

[0191] Fig. 13C Another two-step random access procedure is shown. Fig.13A and Fig. 13B Similar to the random access procedure shown, the base station may transmit a configuration message 1330 to the UE before the procedure is initiated. Configuration message 1330 may be similar to configuration message 1310 and / or configuration message 1320 in some aspects. Fig. 13C The procedure shown includes the transmission of two messages: Msg A 1331 and Msg B 1332.

[0192] 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. Transport block 1342 may include Fig.13A The transmission 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 the same content as the content of Msg 3 1313 shown in FIG. Fig.13A and Fig. 13B Msg 2 1312 (eg, RAR) and / or Fig.13A The content of Msg 4 1314 shown is similar and / or identical.

[0193] The UE can initiate a call for licensed spectrum and / or unlicensed spectrum. Fig. 13C The UE may determine whether to initiate a two-step random access procedure based on one or more factors. The one or more factors may be: the radio access technology being used (e.g., LTE, NR, etc.); whether the UE has a valid TA; the cell size; the RRC state of the UE; the type of spectrum (e.g., licensed vs. unlicensed); and / or any other suitable factors.

[0194] The UE may determine the radio resources and / or uplink transmission power of the preamble 1341 and / or the transport block 1342 included in the Msg A 1331 based on the two-step RACH parameters included in the configuration message 1330. The RACH parameters may indicate the modulation and coding scheme (MCS), time-frequency resources, and / or power control of the preamble 1341 and / or the transport block 1342. The time-frequency resources (e.g., PRACH) used for transmission of the preamble 1341 and the time-frequency resources (e.g., PUSCH) used for transmission of the transport block 1342 may be multiplexed using FDM, TDM, and / or CDM. The RACH parameters may enable the UE to determine the reception timing and downlink channel for monitoring and / or receiving the Msg B 1332.

[0195] The transmission block 1342 may include data (e.g., delay-sensitive data), an identifier of the UE, security information, and / or device information (e.g., an International Mobile Subscriber Identity (IMSI)). The base station may transmit Msg B 1332 as a response to Msg A 1331. Msg B 1332 may include at least one of the following: a preamble identifier; a timing high-level command; a power control command; an uplink grant (e.g., a radio resource assignment and / or MCS); a UE identifier for contention resolution; and / or an RNTI (e.g., a C-RNTI or a TC-RNTI). The UE may determine that the two-step random access procedure is successfully completed if the following conditions exist: the preamble identifier in Msg B 1332 matches the preamble transmitted by the UE; and / or the identifier of the UE in Msg B 1332 matches the identifier of the UE in Msg A 1331 (e.g., transmission block 1342).

[0196] The UE and the base station may exchange control signaling. The control signaling may be referred to as L1 / L2 control signaling and may originate from the PHY layer (e.g., layer 1) and / or the MAC layer (e.g., layer 2). The control signaling may 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.

[0197] Downlink control signaling may include: downlink scheduling assignment; uplink scheduling grant indicating uplink radio resources and / or transport format; time slot format information; preemption indication; power control command; and / or any other suitable signaling. The UE may receive downlink control signaling in a payload transmitted by the base station on a physical downlink control channel (PDCCH). The payload transmitted on the PDCCH may be referred to as downlink control information (DCI). In some scenarios, the PDCCH may be a group common PDCCH (GC-PDCCH) common to a group of UEs.

[0198] The base station may attach one or more cyclic redundancy check (CRC) parity bits to the DCI to facilitate 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 an identifier of the UE (or an identifier of the group of UEs). Scrambling the CRC parity bits with the identifier may include a Modulo-2 addition (or an 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).

[0199] DCI can be used for different purposes. The purpose can be indicated by the type of RNTI used to scramble the CRC parity bits. For example, a DCI with CRC parity bits scrambled with a paging RNTI (P-RNTI) can indicate paging information and / or system information change notification. The P-RNTI can be predefined as hexadecimal "FFFE". A DCI with CRC parity bits scrambled with a system information RNTI (SI-RNTI) can indicate a broadcast transmission of system information. The SI-RNTI can be predefined as hexadecimal "FFFF". A DCI with CRC parity bits scrambled with a random access RNTI (RA-RNTI) can indicate a random access response (RAR). A DCI with CRC parity bits scrambled with a cell RNTI (C-RNTI) can indicate a dynamically scheduled unicast transmission and / or the triggering of a PDCCH ordered random access. A DCI with CRC parity bits scrambled with a temporary cell RNTI (TC-RNTI) can indicate contention resolution (e.g., similar to Fig.13AThe other RNTIs configured by the base station to the UE may include: a configured scheduling RNTI (CS-RNTI), a transmission power control PUCCH RNTI (TPC-PUCCH-RNTI), a transmission power control PUSCH RNTI (TPC-PUSCH-RNTI), a transmission power control SRS RNTI (TPC-SRS-RNTI), an interruption RNTI (INT-RNTI), a slot format indication RNTI (SFI-RNTI), a semi-persistent CSI RNTI (SP-CSI-RNTI), a modulation and coding scheme cell RNTI (MCS-C-RNTI), etc.

[0200] 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 scheduling of PUSCH in a 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 scheduling of PUSCH in a cell (e.g., with a larger DCI payload than DCI format 0_0). DCI format 1_0 may be used for scheduling of PDSCH in a cell. DCI format 1_0 may be a fallback DCI format (e.g., with a compact DCI payload). DCI format 1_1 may be used for scheduling of PDSCH in a cell (e.g., with a larger DCI payload than DCI format 1_0). DCI format 2_0 may be used to provide a 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 to the UE is expected. DCI format 2_2 may be used to transmit a transmission power control (TPC) command for PUCCH or PUSCH. DCI formats 2_3 may be used to transmit a set of TPC commands for SRS transmission by one or more UEs. DCI formats for new functions may be defined in future releases. DCI formats may have different DCI sizes, or may share the same DCI size.

[0201] After scrambling the DCI with the RNTI, the base station may process the DCI with channel coding (e.g., polarity coding), rate matching, scrambling, and / or QPSK modulation. The base station may map the coded and modulated DCI on resource elements used for and / or configured for PDCCH. Based on the payload size of the DCI and / or the coverage of the base station, the base station may transmit the DCI via a PDCCH occupying multiple consecutive control channel elements (CCEs). The number of consecutive CCEs (referred to as the aggregation level) may be 1, 2, 4, 8, 16, and / or any other suitable number. CCE may include the number of resource element groups (REGs) (e.g., 6). REG may include a resource block in an OFDM symbol. The mapping of the coded and modulated DCI on the resource elements may be based on the mapping of CCEs and REGs (e.g., CCE to REG mapping).

[0202] Fig.14A An example of a CORESET configuration for a bandwidth portion is shown. A base station may transmit DCI via a PDCCH on one or more control resource sets (CORESETs). A CORESET may include time-frequency resources in which a UE attempts to decode DCI using one or more search spaces. A base station may configure a CORESET in the time-frequency domain. Fig.14A In the example of FIG. 1401 , the first CORESET 1401 and the second CORESET 1402 appear at the first symbol in the time slot. The first CORESET 1401 overlaps the second CORESET 1402 in the frequency domain. The third CORESET 1403 appears at the third symbol in the time slot. The fourth CORESET 1404 appears at the seventh symbol in the time slot. The CORESETs may have different numbers of resource blocks in the frequency domain.

[0203] Fig. 14B An example of CCE to REG mapping for DCI transmission on CORESET and PDCCH processing is shown. The CCE to REG mapping can be an interlaced mapping (e.g., for the purpose of providing frequency diversity) or a non-interlaced mapping (e.g., for the purpose of facilitating interference coordination and / or frequency selective transmission of control channels). The base station can perform different or the same CCE to REG mapping for different CORESETs. A CORESET can be associated with the CCE to REG mapping through RRC configuration. A 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) for PDCCH reception in the CORESET.

[0204] The base station may transmit an RRC message including configuration parameters of one or more CORESETs and one or more search space sets to the UE. The configuration parameters may indicate an association between a search space set and a 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 for each aggregation level; the PDCCH monitoring period and the PDCCH monitoring type; one or more DCI formats to be monitored by the UE; and / or whether the search space set is a common search space set or a UE-specific search space set. The set of CCEs in the common search space set 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 UE's identity (e.g., C-RNTI).

[0205] like Fig. 14B As 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 of the CORESET based on the configuration parameters of the CORESET (e.g., interlaced or non-interlaced and / or mapping parameters). The UE may determine the number of search space sets configured on the CORESET based on the RRC message (e.g., up to 10). The UE may monitor a set of PDCCH candidates according to the configuration parameters of the search space set. The UE may monitor a set of PDCCH candidates in one or more CORESETs for detecting one or more DCIs. Monitoring may include decoding one or more PDCCH candidates in the set of PDCCH candidates according to the monitored DCI format. Monitoring may include decoding the DCI content of one or more PDCCH candidates, which have possible (or configured) PDCCH 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. 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., scrambled bits of the CRC parity bits of the DCI matching the RNTI value). The UE may process the information contained in the DCI (e.g., scheduling assignments, uplink grants, power control, time slot format indications, downlink preemption, etc.).

[0206] The UE may transmit uplink control signaling (e.g., uplink control information (UCI)) to the base station. The uplink control signaling transmission may include a hybrid automatic repeat request (HARQ) confirmation for the received DL-SCH transport block. The UE may transmit the HARQ confirmation after receiving the DL-SCH transport block. The uplink control signaling may include channel state information (CSI) indicating the channel quality of the physical downlink channel. The UE may transmit the CSI to the base station. Based on the received CSI, the base station may determine the transmission format parameters (e.g., including multiple antennas and beamforming schemes) for downlink transmission. The uplink control signaling may include a scheduling request (SR). The UE may transmit an SR indicating that uplink data is available for transmission to the base station. The UE may transmit UCI (e.g., HARQ confirmation (HARQ-ACK), CSI report, SR, etc.) via a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH). The UE may transmit uplink control signaling via PUCCH using one of several PUCCH formats.

[0207] There may be five PUCCH formats, and the UE may determine the PUCCH format based on the size of the UCI (e.g., the number of uplink symbols for UCI transmission and the number of UCI bits). PUCCH format 0 may have a length of one or two OFDM symbols and may include two or fewer bits. If the transmission exceeds one or two symbols and the number of HARQ-ACK information bits (HARQ-ACK / SR bits) with positive or negative SR is one or two, the wireless device may use PUCCH format 0 to transmit UCI in the PUCCH resource. PUCCH format 1 may occupy between four and fourteen OFDM symbols and may include two or fewer bits. If four or more symbols are transmitted and the number of HARQ-ACK / SR bits is one or two, the UE may use PUCCH format 1. PUCCH format 2 may occupy one or two OFDM symbols and may include more than two bits. If the transmission exceeds one or two symbols and the number of UCI bits is two or more, the UE may use PUCCH format 2. PUCCH format 3 may occupy between four and fourteen OFDM symbols and may include more than two bits. If four or more symbols are transmitted, the number of UCI bits is two or more, and the PUCCH resources do not include orthogonal cover codes, the UE may use PUCCH format 3. PUCCH format 4 may occupy between four and fourteen OFDM symbols and may include more than two bits. If four or more symbols are transmitted, the number of UCI bits is two or more, and the PUCCH resources include orthogonal cover codes, the UE may use PUCCH format 4.

[0208] The base station may transmit configuration parameters of multiple PUCCH resource sets to the UE using, for example, an RRC message. The multiple PUCCH resource sets (e.g., up to four sets) may be configured on the uplink BWP of the cell. The PUCCH resource set may be configured with: a PUCCH resource set index; multiple PUCCH resources having PUCCH resources identified by a PUCCH resource identifier (e.g., pucch-Resourceid); and / or multiple (e.g., maximum number) 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 of the multiple PUCCH resource sets (e.g., HARQ-ACK, SR, and / or CSI) 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 the first PUCCH resource set with 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 the 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 the 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".

[0209] After determining a PUCCH resource set from a plurality of PUCCH resource sets, the UE may determine PUCCH resources for UCI (HARQ-ACK, CSI, and / or SR) transmission from the PUCCH resource set. The UE may determine the PUCCH resources based on a PUCCH resource indicator in a DCI (e.g., a DCI format 1_0 or a DCI for 1_1) received on the PDCCH. The three-bit PUCCH resource indicator in the DCI may indicate one PUCCH resource in eight PUCCH resources in the PUCCH resource set. Based on the PUCCH resource indicator, the UE may use the PUCCH resources indicated by the PUCCH resource indicator in the DCI to transmit UCI (HARQ-ACK, CSI, and / or SR).

[0210] Fig.15 An example of a wireless device 1502 communicating with a base station 1504 according to 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 shown or any other communication network. Fig.15 Only one wireless device 1502 and one base station 1504 are shown in FIG. 1 , 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 Fig.15 Configurations the same or similar to those shown.

[0211] The base station 1504 may connect the wireless device 1502 to a core network (not shown) by radio communication via an air interface (or radio interface) 1506. The direction of communication from the base station 1504 to the wireless device 1502 over the air interface 1506 is referred to as downlink, while the direction of communication from the wireless device 1502 to the base station 1504 over the air interface is referred to as uplink. Downlink transmissions may be separated from uplink transmissions using FDD, TDD, and / or some combination of the two duplexing techniques.

[0212] In the downlink, data to be sent from base station 1504 to wireless device 1502 may be provided to processing system 1508 of base station 1504. The data may be provided to processing system 1508 via, for example, a core network. In the uplink, data to be sent from wireless device 1502 to base station 1504 may be provided to processing system 1518 of wireless device 1502. Processing system 1508 and processing system 1518 may implement layer 3 and layer 2 OSI functions to process data for transmission. Layer 2 may include, for example, information about Figure 2A , Figure 2B , Figure 3 and Figure 4A Layer 3 may include the following: Figure 2B RRC layer.

[0213] After processing by processing system 1508, data to be transmitted to wireless device 1502 may be provided to transmission processing system 1510 of base station 1504. Similarly, after processing by processing system 1518, data to be transmitted to base station 1504 may be provided to transmission processing system 1520 of wireless device 1502. Transmission processing system 1510 and transmission processing system 1520 may implement layer 1 OSI functions. Layer 1 may include information about Figure 2A , Figure 2B , Figure 3 and Figure 4A For transmission processing, the PHY layer may perform, for example, forward error correction coding of transport channels, interleaving, rate matching, mapping of transport channels to physical channels, modulation of physical channels, multiple-input multiple-output (MIMO) or multi-antenna processing, etc.

[0214] At base station 1504, receive processing system 1512 may receive uplink transmissions from wireless device 1502. At wireless device 1502, receive processing system 1522 may receive downlink transmissions from base station 1504. Receive processing system 1512 and receive processing system 1522 may implement layer 1 OSI functions. Layer 1 may include information about Figure 2A , Figure 2B , Figure 3 and Figure 4A For reception processing, the PHY layer may perform, for example, error detection, forward error correction decoding, deinterleaving, demapping of transport channels to physical channels, demodulation of physical channels, MIMO or multi-antenna processing, etc.

[0215] like Fig.15 As shown, the wireless device 1502 and the base station 1504 may include multiple antennas. The multiple antennas may be used to perform one or more MIMO or multi-antenna techniques, such as spatial multiplexing (e.g., single-user MIMO or multi-user MIMO), transmit / receive diversity, and / or beamforming. In other examples, the wireless device 1502 and / or the base station 1504 may have a single antenna.

[0216] Processing system 1508 and processing system 1518 may be associated with memory 1514 and memory 1524, respectively. Memory 1514 and memory 1524 (e.g., one or more non-transitory computer-readable media) may store computer program instructions or codes that may be executed by processing system 1508 and / or processing system 1518 to perform one or more of the functions discussed herein. Fig.15 Not shown, transmit processing system 1510, transmit processing system 1520, receive processing system 1512, and / or receive processing system 1522 may be coupled to a memory (e.g., one or more non-transitory computer-readable media) storing computer program instructions or code that may be executed to perform one or more of their respective functions.

[0217] The processing system 1508 and / or the 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 device, discrete gate and / or transistor logic, discrete hardware components, on-board units, or any combination thereof. The processing system 1508 and / or the 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 functions that may enable the wireless device 1502 and the base station 1504 to operate in a wireless environment.

[0218] The processing system 1508 and / or the processing system 1518 may be connected to one or more peripheral devices 1516 and one or more peripheral devices 1526, respectively. The one or more peripheral devices 1516 and the one or more peripheral devices 1526 may include software and / or hardware that provides features and / or functionality, such as a speaker, a microphone, a keyboard, a display, a touch pad, a power supply, a satellite transceiver, a universal serial bus (USB) port, a hands-free headset, a frequency modulation (FM) radio unit, a media player, an Internet browser, an electronic control unit (e.g., for a motor vehicle), and / or one or more sensors (e.g., an accelerometer, a gyroscope, a temperature sensor, a radar sensor, a lidar sensor, an ultrasonic sensor, a light sensor, a camera, etc.). The processing system 1508 and / or the 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 one or more peripheral devices. The processing system 1518 in the wireless device 1502 can receive power from the power source and / or can be configured to distribute power to other components in the wireless device 1502. The power source can include one or more power sources, such as batteries, solar cells, fuel cells, or any combination thereof. The processing system 1508 and / or the processing system 1518 can be connected to the GPS chipset 1517 and the GPS chipset 1527, respectively. The GPS chipset 1517 and the GPS chipset 1527 can be configured to provide the geographical location information of the wireless device 1502 and the base station 1504, respectively.

[0219] Fig.16AAn exemplary structure for uplink transmission is shown. The baseband signal representing the physical uplink shared channel can perform one or more functions. The one or more functions may include at least one of the following: scrambling; modulating scrambled bits to generate complex-valued symbols; mapping complex-valued modulated symbols to one or several transmission layers; transform precoding to generate complex-valued symbols; precoding of complex-valued symbols; mapping of 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 the like. In the example, when transform precoding is enabled, an SC-FDMA signal for uplink transmission can be generated. In the example, when transform precoding is not enabled, the uplink transmission can be performed by Fig.16A Generate a CP-OFDM signal for uplink transmission. These functions are shown as examples, and it is contemplated that other mechanisms may be implemented in various embodiments.

[0220] Fig. 16B An exemplary structure for modulation and up-conversion of a baseband signal to a carrier frequency is shown. The baseband signal may be a complex-valued SC-FDMA or CP-OFDM baseband signal and / or a complex-valued physical random access channel (PRACH) baseband signal for an antenna port. Filtering may be employed prior to transmission.

[0221] Fig. 16C An exemplary structure for downlink transmission is shown. A baseband signal representing a physical downlink channel may perform one or more functions. The one or more functions may include: scrambling coded bits in a codeword to be transmitted on a physical channel; modulating the scrambled bits to generate complex-valued modulation symbols; mapping the complex-valued modulation symbols onto one or several transmission layers; precoding of complex-valued modulation symbols on layers for transmission on antenna ports; mapping complex-valued modulation symbols for antenna ports to resource elements; generating complex-valued time-domain OFDM signals for antenna ports; and the like. These functions are shown as examples, and it is contemplated that other mechanisms may be implemented in various embodiments.

[0222] Fig.16D Another exemplary structure for modulation and up-conversion of a baseband signal to a carrier frequency is shown. The baseband signal may be a complex valued OFDM baseband signal at an antenna port. Filtering may be employed prior to transmission.

[0223] The wireless device may receive one or more messages (e.g., RRC messages) including configuration parameters of multiple cells (e.g., primary cells, secondary cells) from a base station. The wireless device may communicate with at least one base station (e.g., two or more base stations in dual connectivity) via the multiple cells. The one or more messages (e.g., as part of the configuration parameters) may include parameters for configuring the wireless device at the physical layer, MAC layer, RLC layer, PCDP layer, SDAP layer, and RRC layer. For example, the configuration parameters may include parameters for configuring physical layer and MAC layer channels, bearers, and the like. For example, the configuration parameters may include parameters indicating values ​​of timers for the physical layer, MAC layer, RLC layer, PCDP layer, SDAP layer, RRC layer, and / or communication channels.

[0224] Once started, a timer can start running and continue running until it stops 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., a 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 may not be updated until the timer stops or expires (e.g., due to BWP switching). The timer can be used for the time period / window of the measurement 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 of implementing the timer can be used to measure the time period / window of the 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 the start and expiration of the 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 embodiments can be provided to restart the measurement of the time window.

[0225] In an example, a small data transfer (SDT) in a wireless network (e.g., LTE, 5G, new radio, NR, etc.) may be interpreted as an early data transfer (EDT). The term SDT and the term EDT may be interchangeable with each other. Early data transfer initially performed for uplink data transmission may be referred to as mobile originated early data transfer (MO-EDT), uplink EDT, uplink SDT, mobile originated SDT (MO-SDT), etc. Early data transfer initially performed for downlink data transmission (e.g., initiated based on a paging procedure) may be referred to as mobile terminated early data transfer (MT-EDT), downlink EDT, downlink SDT, mobile terminated SDT (MT-SDT), etc.

[0226] In an example, MO-EDT may allow one uplink data transmission during and / or after a random access procedure, optionally followed by at least one downlink data transmission. MO-EDT may be triggered when upper layers request to establish or resume an RRC connection for mobile originated data (e.g., which may not be signaling or SMS) and / or the uplink data size may be less than or equal to the transport block (TB) size indicated in the system information. MO-EDT may not be used for data on the control plane when user plane Cellular Internet of Things (CIoT) EPS / 5GS optimization is used. MO-EDT may be applicable to low complexity (BL) UEs with reduced bandwidth, UEs in enhanced coverage (e.g., coverage enhancement UEs, CE UEs), narrowband IoT (NB-IoT) UEs, and / or reduced capability (RedCap) UEs.

[0227] In an example, MO-EDT for control plane CIoT EPS optimization and / or control plane CIoT 5GS optimization can be characterized as follows. Uplink user data can be transmitted in a NAS message in a UL RRC Early Data Request message attached on CCCH. Downlink user data can optionally be transmitted in a NAS message in a DL RRC Early Data Complete message attached on CCCH. The UE may not transition to an RRC connection.

[0228] Fig.17 An example of a MO-EDT procedure for control plane CIoT EPS optimization and / or control plane CIoT 5GS optimization is shown. At a connection establishment request for mobile originated (MO) data from an upper layer, the UE may initiate a MO-EDT procedure and / or may select a random access preamble configured for EDT. The UE may perform a random access procedure by sending the selected random access preamble. The UE may send an RRC early data request message for connecting user data on the CCCH. For EPS or 5GS, if enabled in the cell, the UE may instruct the AS to release assistance information (RAI). For EPS, the eNB or gNB may initiate an S1-AP initial UE message procedure to forward NAS messages and / or establish an S1 connection. For 5GS, the ng-eNB or gNB may initiate an NG-AP initial UE message procedure to forward NAS messages. The (ng-)eNB or gNB may indicate that the connection is triggered for EDT (and / or SDT).

[0229] For EPS, the MME may request the S-GW to reactivate the EPS bearer for the UE. For 5GS, the AMF may determine the PDU session contained / indicated in the NAS message from the UE. For EPS, the MME may send uplink data to the S-GW. For 5GS, the AMF may send the PDU session ID and / or uplink data to the SMF, and / or the SMF may forward the uplink data to the UPF. For EPS, if downlink data is available, the S-GW may send downlink data to the MME For 5GS, if downlink data is available, the UPF may forward the downlink data to the SMF, and / or the SMF may forward the downlink data to the AMF. If downlink data is received from the S-GW and / or SMF, the MME or AMF may forward the downlink data to the eNB / ng-eNB or gNB via the DL NAS transfer procedure, and / or may indicate whether more data is expected. In the example, the MME or AMF may trigger a connection establishment indication procedure and / or may indicate whether more data is expected. In an example, if no more data is expected, the (ng-)eNB or gNB may send an RRC Early Data Complete message on CCCH to keep the UE in RRC_IDLE or RRC_INACTIVE. If downlink data is received, the downlink data may be connected in the RRC Early Data Complete message.

[0230] For EPS, the S1 connection may be released and / or the EPS bearers may be deactivated. For 5GS, the AN release procedure is initiated. If the MME / AMF or (ng-)eNB or gNB decides to move the UE to the RRC_CONNECTED state, an RRCConnectionSetup message or an RRCResume message may be sent to fall back to the RRC connection establishment / setup / resumption procedure. The (ng-)eNB or gNB may discard a zero-length NAS PDU received in an RRCConnectionSetupComplete message. If neither RRCConnectionSetup / establishment / resume nor (in the case of fallback) is received in response to RRCArlyDataRequest, the UE may consider the UL data transmission to be unsuccessful.

[0231] In an example, MO-EDT for user plane CIoT EPS optimization and / or user plane CIoT 5GS optimization can be characterized as follows. NextHopChainingCount (NCC) can be provided to the UE in an RRCConnectionRelease message and / or an RRC release message with a pause indication. Uplink user data can be transmitted on a DTCH multiplexed with a UL RRCConnectionResumeRequest message or an RRC recovery request message on the CCCH. Downlink user data can optionally be transmitted on a DTCH multiplexed with a DL RRCConnectionRelease message or an RRC release message on the DCCH. The short resume MAC-I (shortResumeMAC-I) can be reused as an authentication token for the RRCConnectionResumeRequest message and / or the RRC recovery request message. The short resume MAC-I can be calculated using the integrity key from the previous connection. User data in the uplink and / or downlink can be encrypted. The key can be derived using the NextHopChainingCount (NCC) provided in the RRCConnectionRelease message and / or the RRC release message of the previous RRC connection. The RRCConnectionRelease message and / or the RRC Release message may be integrity protected and / or encrypted using the newly derived key.There may be no transition from the RRC Idle state and / or the RRC Inactive state to the RRC Connected state.

[0232] Fig.18An example of a MO-EDT procedure for user plane CIoT EPS optimization and / or user plane CIoT 5GS optimization is shown. At the time of a connection recovery request for mobile originated data from an upper layer, the UE may initiate a MO-EDT procedure and / or may select a random access preamble configured for EDT. The UE may send an RRCConnectionResumeRequest to the eNB and / or gNB, including a recovery ID, an establishment cause, and / or an authentication token. The UE may recover all SRBs and / or DRBs. The UE may recover some of the SRBs and / or DRBs configured in the previous RRC connection. The UE may derive new security keys using the NextHopChainingCount provided in the RRCConnectionRelease message of the previous RRC connection, and / or may reestablish AS security. User data may be encrypted and / or transmitted via a DTCH multiplexed with an RRCConnectionResumeRequest message on the CCCH. If enabled in the cell, the UE may instruct the AS to release auxiliary information (RAI). The eNB may initiate an S1-AP context recovery procedure to recover the S1 connection and / or reactivate the S1-U bearer. The MME may request the S-GW to reactivate the S1-U bearer for the UE. The MME may confirm the UE context recovery to the eNB. Uplink data may be delivered to the S-GW. If downlink data is available, the S-GW may send the downlink data to the eNB. If no more data is expected, the eNB may initiate a suspension of the S1 connection and / or deactivation of the S1-U bearer for the UE. The eNB may send an RRCConnectionRelease message and / or an RRC release message to keep the UE in an RRC_IDLE state and / or an RRC inactive state. The RRCConnectionRelease message and / or the RRC release message may include releaseCause, resumeID, NextHopChainingCount (NCC) and / or drb-ContinueROHC set to rrc-Suspend, which may be stored by the UE. If downlink data is received, the downlink data may be sent encrypted via a DTCH, which is multiplexed with the RRCConnectionRelease message and / or the RRC release message via the DCCH.

[0233] like Fig.18As shown, upon a connection resumption request for mobile originated data from an upper layer, the UE may initiate a MO-EDT procedure and / or may select a random access preamble configured for EDT. The UE may send an RRCConnectionResumeRequest and / or RRC resumption request message to the ng-eNB and / or gNB, including an I-RNTI, a resumption cause and / or an authentication token. The UE may resume all SRBs and DRBs. The UE may resume some of the SRBs and / or DRBs configured in the previous RRC connection. The UE may derive new security keys using the NextHopChainingCount (NCC) provided in the RRCConnectionRelease message and / or RRC release message of the previous connection, and / or may reestablish AS security. User data may be encrypted and / or transmitted via a DTCH multiplexed with an RRCConnectionResumeRequest message and / or an RRC resumption message on the CCCH. The UE may indicate AS release assistance information (RAI). Uplink data may be delivered to the UPF. The ng-eNB and / or gNB may send an NG-AP Context Resume Request message to the AMF to resume the connection. If the UE includes AS Release Assistance Information indicating that there are no additional UL / DL higher layer PDUs, the ng-eNB and / or gNB may request an immediate transition to RRC IDLE and / or RRC INACTIVE state with suspension. If the AMF does not receive a request for an immediate transition to RRC IDLE and / or RRC INACTIVE state with suspension, or the AMF knows that downlink data or signaling is pending, the AMF may request the SMF to resume the PDU session. The AMF may send an NG-AP Context Resume Response to the ng-eNB and / or gNB. If the AMF receives a request for an immediate transition to RRC IDLE and / or RRC INACTIVE state with suspension, and / or if there is no downlink data or signaling pending, the AMF may include a suspension indication. The AMF may keep the UE in CM-IDLE with suspension. If the AMF includes a suspension indication, the ng-eNB and / or gNB may perform an RRC release procedure with suspension. If the AMF does not include a suspension indication and / or if the UE includes AS release assistance information indicating a single downlink data transmission after an uplink transmission, the ng-eNB and / or gNB may wait for the downlink data to arrive. The ng-eNB or gNB may initiate a NG-AP UE context suspension procedure to inform the AMF that the RRC connection may be suspended. The AMF may request the SMF to suspend the PDU session. The SMF may request the UPF to release the tunnel information of the UE.The eNB / ng-eNB and / or gNB may send an RRCConnectionRelease message and / or an RRC Release message to keep the UE in the RRC_IDLE and / or RRC Inactive state. The RRCConnectionRelease message and / or the RRC Release message may include releaseCause, I-RNTI, NextHopChainingCount (NCC), and / or drb-ContinueROHC, which may be set to rrc-Suspend, and which may be stored by the UE. If downlink data (e.g., subsequent downlink data) is received, the downlink data may be sent encrypted via the DTCH, which is multiplexed with the RRCConnectionRelease message and / or the RRC Release message on the DCCH.

[0234] In an example, if the MME / AMF or (ng-)eNB / gNB decides that the UE moves in the RRC_CONNECTED state, an RRCConnectionResume message and / or an RRC resume / setup message may be sent to fall back to the RRC connection resumption procedure. The RRCConnectionResume message and / or the RRC resume / setup message may be integrity protected and / or encrypted with a derived key. The UE may ignore the NextHopChainingCount (NCC) included in the RRCConnectionResume message and / or the RRC resume message. Downlink data may be transmitted via the DTCH multiplexed with the RRCConnectionResume message and / or the RRC resume / setup message. An RRCConnectionSetup and / or an RRC setup message may be sent to fall back to the RRC connection establishment / setup procedure. In the example, if neither an RRCConnectionRelease message (RRC release message) nor an RRCConnectionResume message (RRC resume / setup message) is received in response to an RRCConnectionResumeRequest message and / or an RRC resume request message of MO-EDT, the UE may consider that the uplink data transmission is unsuccessful.

[0235] In the example, Fig.19As shown, for MO-EDT for user plane CIoT EPS optimization and / or user plane CIoT 5GS optimization, the RRC connection can be restored in a (ng-)eNB (e.g., a new (ng-)eNB) and / or a gNB (e.g., a new gNB) that is different from the base station (old (ng-)eNB and / or old gNB) where the RRC connection is suspended. Context extraction can be used to handle inter-(ng-)eNB or inter-gNB connection restoration. The new (ng-)eNB or new gNB can retrieve the UE context from the old (ng-)eNB and / or old gNB via the X2 (Xn) interface. The new (ng-)eNB or new gNB can provide a restoration ID for EPS or an I-RNTI for 5GS, which the old (ng-)eNB or old gNB can use to identify the UE context of the UE.

[0236] Fig.19An example of a MO-EDT procedure for user plane CIoT EPS optimization and / or user plane CIoT 5GS optimization in different eNB / ng-eNB and / or different gNB (e.g., base station relocation scenario) is shown. The new (ng-)eNB or new gNB may locate / determine the old (ng-)eNB using the Resume ID (e.g., for EPS) or I-RNTI (e.g., for 5GS) and / or may retrieve the UE context by performing a Retrieve UE Context procedure via an X2-AP (for EPS) or an Xn-AP (for 5GS). The old (ng-)eNB may respond with a UE context associated with the Resume ID (e.g., for EPS) or I-RNTI (e.g., for 5GS). For EPS, the new eNB or new gNB may initiate an S1-AP path switch procedure to establish an S1UE associated signaling connection to the serving MME and / or request the MME to restore the UE context. For 5GS, the new ng-eNB or new gNB may initiate a NG-AP path switching procedure to establish an NG UE associated signaling connection to the serving AMF and / or request the AMF to restore the UE context. For EPS, the MME may request the S-GW to activate the S1-U bearer for the UE and / or may update the downlink path. For 5GS, the AMF may request the SMF to restore the PDU session. The SMF may request the UPF to create tunnel information for the UE and / or update the downlink path. For EPS, after the S1-AP path switching procedure, the new eNB and / or new gNB may trigger the release of the UE context at the old eNB or old gNB by performing the UE context release procedure via X2-AP. For 5GS, after the NG-AP path switching procedure, the new ng-eNB and / or new gNB may trigger the release of the UE context at the old ng-eNB and / or old gNB by performing the UE context release procedure via Xn-AP. Uplink data may be delivered to the S-GW and / or UPF.

[0237] In an example, MT-EDT can be used for a single downlink data transmission during a random access procedure. If the UE and / or the network supports MT-EDT and / or if there is a single DL data transmission of the UE, the MT-EDT can be initiated by the MME, AMF / SMF or gNB. MT-EDT for control plane CIoT EPS / 5GS optimization and / or for user plane CIoT EPS / 5GS optimization can be characterized as follows. The UE can report support for MT-EDT for control plane CIoT EPS / 5GS optimization and / or for user plane CIoT EPS / 5GS optimization via NAS-level signaling (e.g., via a NAS message). The downlink data size may be included / indicated in the S1-AP or NG-AP paging message of the UE. The MT-EDT indication may be included in the paging message of the UE on the Uu interface. For user plane CIoT EPS / 5GS optimization, the NextHopChainingCount (NCC) may be provided to the UE in an RRCConnectionRelease message and / or an RRC release message with a pause indication. In response to a paging message including / containing an MT-EDT indication, if the upper layer requests to establish or resume an RRC connection for a mobile terminated call, the UE may trigger a MO-EDT procedure for control plane CIoT EPS / 5GS optimization or for user plane CIoT EPS / 5GS optimization. A UE performing MT-EDT may not transition to an RRC connected state. MT-EDT may be applicable to BL UEs, UEs in enhanced coverage (e.g., CE UEs), and / or NB-IoT UEs.

[0238] In an example, small data transmission may include communication of uplink / downlink data between a wireless device and a network (e.g., a base station, a core network, a data network, etc.) without establishing / restoring an RRC connection of the wireless device and / or without transitioning the wireless device to an RRC connected state.

[0239] In an example, transmission using preconfigured uplink resources (PUR) may allow at least one uplink transmission from RRC_IDLE (RRC idle state) and / or RRC_INACTIVE (RRC inactive state) using PUR without performing a random access procedure. The (ng-)eNB and / or gNB may enable transmission using PUR if supported by the UE and / or (ng-)eNB.

[0240] In an example, when in RRC_CONNECTED mode / state, the UE may request to be configured with a PUR and / or release a PUR configuration. The (ng-)eNB / gNB may decide to configure a PUR, which may be based on the UE's request, the UE's subscription information and / or local policy. The PUR may be valid in the cell receiving the configuration.

[0241] Transmission using PUR may be triggered when the upper layers of the UE request to establish or resume an RRC connection. Transmission using PUR may be triggered when the UE has data to transmit. Transmission using PUR may be triggered when the UE has a valid PUR for transmission and / or meets the TA verification criteria. Transmission using PUR may be applicable to BL UEs, UEs in enhanced coverage and / or NB-IoT UEs. Fig.23 An example of transmission using PUR is shown.

[0242] In the example, Fig. 20 As shown, the PUR configuration request and / or PUR configuration procedure can be used for control plane CIoTEPS / 5GS optimization and / or user plane CIoT EPS / 5GS optimization. The UE can send a PUR configuration request to a base station (e.g., gNB, eNB). The base station can send an RRC connection release indication and PUR configuration parameters to the UE. The PUR configuration parameters can be based on the PUR configuration request. In the example, Fig. 20 As shown, the UE may be in RRC_CONNECTED and PUR may be enabled in the cell. The UE may indicate to the (ng-)eNB or gNB that the UE is interested in being configured with a PUR by sending a PUR Configuration Request message that provides information about the requested resources (e.g., number of occurrences, periodicity, time offset, TBS, RRCAck, etc.). The UE may indicate to the (ng-)eNB or gNB in ​​a PURConfigurationRequest message that the UE is interested in the configured PUR to be released. When the (ng-)eNB or gNB moves the UE to RRC_IDLE or RRC_INACTIVE (e.g., based on a previous UE PUR configuration request, subscription information, and / or local policy), the (ng-)eNB or gNB may decide to provide PUR resources to the UE or release existing PUR resources. The (ng-)eNB or gNB may include parameters for the PUR configuration or a PUR release indication in the RRC connection release message. For UEs optimized using the control plane CIoT EPS / 5GS, the (ng-)eNB or gNB may provide a PUR configuration ID with the PUR configuration. If available, the UE may include the PUR configuration ID in the RRC connection setup / resumption complete message when establishing / resume an RRC connection that does not use PUR resources.

[0243] In an example, when the UE accesses another cell, when the PUR is no longer enabled in the cell, and / or when the PUR resources are not used for a configured number of consecutive occasions, the PUR configuration may be released at the UE and / or (ng-)eNB / gNB. In an example, the UE and the PUR configuration may be linked based on the configured PUR resources.

[0244] In the example, Fig.21 An example of transmission using a PUR for control plane CIoT EPS optimization and / or for control plane CIoT5GS optimization is shown. Uplink user data may be transmitted using PUR resources in a NAS message in an RRC Early Data Request message attached on CCCH. If there is no downlink data, the (ng-)eNB or gNB may terminate the procedure by sending a Layer 1 acknowledgment, which optionally contains a Time Advance Command, a MAC Time Advance Command and / or an RRC Early Data Complete without user data. Downlink user data may be transmitted in a NAS message in an RRC Early Data Complete message attached on CCCH. The UE may not transition to an RRC connection.

[0245] exist Fig.21In the example, the UE may determine that PUR resources may be used (e.g., PUR is enabled in the cell, valid time alignment, etc.). The UE may transmit via PUR resources. If the uplink data is too large to be included in the RRC early data request, the UE may use PUR resources to transmit the RRC connection request. The procedure may fall back to the RRC connection establishment procedure and / or a new C-RNTI may be assigned. The (ng-)eNB or gNB may request the UE to abort transmission using PUR by sending a Layer 1 fallback indication. In the example, for EPS, the eNB or gNB may initiate an S1-AP or N2 / 3 initial UE message procedure to forward NAS messages and / or may establish an S1 or N2 / N3 connection. For 5GS, the ng-eNB or gNB may initiate an NG-AP initial UE message procedure to forward NAS messages. The (ng-)eNB or gNB may indicate that the connection is triggered for EDT. In the example, for EPS, the MME may request the S-GW to reactivate the EPS bearer for the UE. For 5GS, the AMF may determine the PDU session included in the NAS message. For EPS, the MME may send uplink data to the S-GW. For 5GS, the AMF may send the PDU session ID and / or uplink data to the SMF. The SMF may forward the uplink data to the UPF. In the example, for EPS, if downlink data is available, the S-GW may send downlink data to the MME. For 5GS, if downlink data is available, the UPF may forward the downlink data to the SMF. The SMF may forward the downlink data to the AMF. If downlink data is received from the S-GW or SMF, the MME or AMF may forward the data to the eNB / ng-eNB or gNB via the DL NAS transfer procedure and / or may indicate whether more data is expected. In the example, the MME or AMF may trigger a connection establishment indication procedure and / or may indicate whether more data is expected. If the (ng-)eNB or gNB knows that there is no further data or signaling, the (ng-)eNB or gNB may send a time advance command to update the TA and / or terminate the procedure. In an example, if additional data is expected, the (ng-)eNB or gNB may send an RRC Early Data Complete message on CCCH to keep the UE in RRC_IDLE or RRC_INACTIVE. If downlink data is received, the downlink data may be concatenated in the RRC Early Data Complete message. In an example, if the MME / AMF or (ng-)eNB / gNB decides to move the UE to RRC_CONNECTED mode, an RRC Connection Setup message may be sent to fall back to the RRC connection establishment procedure and / or a new C-RNTI may be assigned.The (ng-)eNB or gNB may discard a zero-length NAS PDU received in the RRC Connection Setup Complete message. In an example, if any of the Layer 1 Ack, MAC Timing Advance Command, RRC Early Data Complete and / or (in case of fallback) RRC Connection Setup is not received in response to an RRC Early Data Request, the UE may consider the UL data transmission to be unsuccessful.

[0246] In the example, Fig. 22 As shown, the UE can use a PUR for user plane CIoT EPS optimization and / or for user plane CIoT 5GS optimization to transmit data. The UE may be in RRC_IDLE or RRC_INACTIVE and / or have valid PUR resources. The next hop link count may be provided to the UE in an RRC connection release message with a pause indication. Uplink user data may be transmitted on a DTCH multiplexed with an RRC connection recovery request message on CCCH. Downlink user data may optionally be transmitted on a DTCH multiplexed with an RRC connection release message on DCCH. User data in the uplink and downlink may be encrypted. A key may be derived using the next hop link count provided in the RRC connection release message of the previous RRC connection. The RRC connection release message may be integrity protected and / or encrypted using a newly derived key. The UE may not transition to an RRC connection. In the example, the UE may use a PUR for user plane CIoT EPS optimization and for user plane CIoT5GS optimization to transmit data.

[0247] exist Fig. 22In the example, the UE may verify the PUR resources based on the configured criteria (e.g., TA verification, RSRP verification, etc.). In the example, the UE may transmit over the PUR resources instead of the resources allocated in the random access response. The UE may send an RRC Connection Resume Request to the eNB or gNB, including its recovery ID, establishment cause and / or authentication token. The UE may restore SRBs and DRBs. The UE may derive new security keys using the NextHopChainingCount provided in the RRC Connection Release message of the previous RRC connection, and / or may reestablish AS security. User data may be encrypted and / or transmitted on the DTCH multiplexed with the RRC Connection Resume Request message on the CCCH. If enabled in the cell, the UE may indicate AS release assistance information. The UE may send an RRCConnectionResumeRequest to the ng-eNB or gNB, including its I-RNTI, recovery cause and / or authentication token. The UE may restore SRBs and DRBs. The UE may derive new security keys using the NextHopChainingCount provided in the RRC Connection Release message of the previous connection, and reestablish AS security. User data may be encrypted and transmitted on the DTCH multiplexed with the RRC Connection Resumption Request message on the CCCH. The UE may instruct the AS to release the assistance information. If the user data is too large to be included in the transmission using the PUR, the UE may use the PUR to transmit the RRC Connection Resumption Request and a segment of the user data. The procedure may fall back to the RRC Connection Resumption procedure. A new C-RNTI may be assigned. The (ng-)eNB or gNB may request the UE to abort transmission using the PUR by sending a Layer 1 Fallback Indication.

[0248] In an example, the eNB or gNB may initiate an S1-AP context recovery procedure to restore the S1 connection and reactivate the S1-U bearers. The MME may request the S-GW to reactivate the S1-U bearers for the UE. The MME may confirm the UE context recovery to the eNB or gNB. Uplink data may be delivered to the S-GW. If downlink data is available, the S-GW may send the downlink data to the eNB or gNB. If no more data is expected, the eNB or gNB may initiate suspension of the S1 connection and / or deactivation of the S1-U bearers.

[0249] In an example, uplink data may be delivered to the UPF. The ng-eNB or gNB may send an NG-AP CONTEXT RESUME REQUEST message to the AMF to resume the connection. If the UE includes AS RELEASE ASSISTANCE INFORMATION indicating that there are no additional UL / DL higher layer PDUs, the ng-eNB or gNB may request an immediate transition to RRC_IDLE with suspension and / or RRC_INACTIVE. In an example, if the AMF does not receive a request for an immediate transition to RRC IDLE with suspension, or the AMF knows that downlink data or signaling is pending, the AMF may request the SMF to resume the PDU session. The AMF may send an NG-AP CONTEXT RESUME RESPONSE to the ng-eNB or gNB. If the AMF receives a request for an immediate transition to RRC IDLE with suspension and / or there is no downlink data or signaling pending, the AMF may include a suspension indication and / or may keep the UE in CM IDLE with suspension. In an example, if the AMF does not include a suspension indication and / or the UE includes AS release assistance information indicating only a single downlink data transmission after the uplink transmission, the ng-eNB or gNB may wait for the DL data to arrive. The ng-eNB or gNB may initiate a NG-AP UE context suspension procedure to inform the AMF that the RRC connection is suspended. The AMF may request the SMF to suspend the PDU session. The SMF may request the UPF to release the tunnel information of the UE.

[0250] The eNB or gNB may send an RRCConnectionRelease message to keep the UE in RRC_IDLE. The message includes releaseCause, resumeID, I-RNTI, NextHopChainingCount, and drb-ContinueROHC set to rrc-Suspend, which are stored by the UE. If downlink data is received, the downlink data may be sent encrypted on the DTCH multiplexed with the RRCConnectionRelease message on the DCCH. In an example, the RRC connection release message may include a time advance command.

[0251] In an example, if the MME / AMF or (ng-)eNB / gNB decides to move the UE to RRC_CONNECTED mode, an RRC connection recovery message may be sent to fall back to the RRC connection recovery procedure. The RRC connection recovery message may be integrity protected and / or encrypted with a key. The UE may ignore the next hop link count included in the RRC connection recovery message. A new C-RNTI may be assigned. Downlink data may be transmitted on the DTCH multiplexed with the RRC connection recovery message. An RRC connection setup may also be sent to fall back to the RRC connection establishment procedure. If neither an RRC connection release nor an RRC connection recovery is received in the case of a fallback in response to an RRC connection recovery request using a PUR, the UE may consider the UL data transmission to be unsuccessful.

[0252] In an example, a transmission using PUR may be initiated by the RRC layer. When initiating a transmission using PUR, the RRC layer may provide at least one of the following to the MAC: PUR-RNTI, duration of the PUR response window pur-ResponseWindowSize, and / or UL grant information. In an example, if the MAC entity has a PUR-RNTI, then for a TTI for which the RRC layer provides an uplink grant for a transmission using PUR, the MAC entity may deliver the uplink grant and / or associated HARQ information to the HARQ entity of the TTI. After the transmission using PUR, the MAC entity may monitor the PDCCH identified by the PUR-RNTI in the PUR response window using the timer pur-ResponseWindowTimer. The PUR response window may start at the subframe / time slot / symbol containing the end of the corresponding PUSCH transmission plus 4 subframes / time slots / symbols. The PUR response window may have a length of pur-ResponseWindowSize. While the pur-ResponseWindowTimer is running, if a PDCCH transmission is addressed to the PUR-RNTI and contains a UL grant for a retransmission, the MAC entity may restart the PUR-ResponseWindowTimer at the last subframe / slot / symbol of the PUSCH transmission corresponding to the retransmission indicated by the UL grant plus 4 subframes / slots / symbols. The MAC entity may stop the pur-ResponseWindowTimer if an L1 ACK for a transmission using PUR is received from a lower layer and / or if the PDCCH transmission is addressed to the PUR-RNTI and the MAC PDU is successfully decoded. If an L1 ACK for a transmission using PUR is received from a lower layer and / or the MAC PDU contains only a timing advance command MAC control element, the MAC entity may indicate to the upper layer that the transmission using PUR is successful and / or the PUR-RNTI may be discarded. If a repetition adjustment for a transmission using PUR is received from a lower layer, the MAC entity may indicate to the upper layer the value of the repetition adjustment. In an example, if a fallback indication for a PUR is received from a lower layer, the MAC entity may stop the pur-ResponseWindowTimer and / or may indicate to the upper layer that a PUR fallback indication is received and / or may discard the PUR-RNTI. If a repetition adjustment for transmission using the PUR is received from a lower layer, the MAC entity may indicate to the upper layer the value of the repetition adjustment. If the pur-ResponseWindowTimer expires, the MAC entity may indicate to the upper layer that the transmission using the PUR has failed and / or discard the PUR-RNTI.

[0253] In an example, the MAC entity may maintain the timer pur-TimeAlignmentTimer by an upper layer (e.g., an RRC layer). In an example, the MAC entity may start the pur-TimeAlignmentTimer when the pur-TimeAlignmentTimer configuration is received from the upper layer. In an example, the MAC entity may stop the pur-TimeAlignmentTimer when the upper layer releases the pur-TimeAlignmentTimer. In an example, when a timing advance command MAC control element is received or a PDCCH indicates a timing advance adjustment, the MAC entity may apply the timing advance command or timing advance adjustment and / or may start / restart the pur-TimeAlignmentTimer. In an example, based on a request from an upper layer, the MAC entity may indicate whether the pur-TimeAlignmentTimer is running.

[0254] In the example, if pur-TimeAlignmentTimer is configured, the UE can consider the timing alignment value for transmission using PUR to be valid when the lower layer confirms that pur-TimeAlignmentTimer is running. In the example, if pur-RSRP-ChangeThreshold (pur-NRSRP-ChangeThreshold in NB-IoT) is configured, the UE can consider the timing alignment value for transmission using PUR to be valid when the serving cell RSRP has not increased by more than increaseThresh and / or the serving cell RSRP has not decreased by more than decreaseThresh since the last TA verification.

[0255] In the example, a UE configured with pur-Config may consider the first PUR opportunity to occur at the H-SFN / SFN / subframe given by H-SFN and / or SFN and the subframe indicated by startSFN and startSubframe. The H-SFN may be determined based on (H-SFNRef+offset) mod 1024 that occurs after FLOOR(offset / 1024) H-SFN cycles. The offset may be given by periodicityAndOffset. Taking into account the hsfn-LSB-Info, the H-SFNRef may correspond to the last subframe of the first transmission of the RRC connection release message containing the pur-Config. The H-SFN cycle may correspond to the duration of 1024 H-SFNs.

[0256] In an example, when pur-NumOccasions is set to one, for the first PUR opportunity, if transmission using PUR has not been initiated or if transmission using PUR has been initiated, after transmission using PUR is completed, the UE may release the pur-Config, may discard the previously stored pur-Config, and / or may indicate to the lower layers that the pur-TimeAlignmentTimer is released (e.g., if pur-TimeAlignmentTimer is configured).

[0257] In the example, Fig.23 In the case where pur-NumOccasions is not set to one (e.g., periodic PUR is configured), the UE may consider that subsequent PUR opportunities occur periodically after the first PUR opportunity at the SFN / subframe indicated by startSubframe and startSFN, and the periodicity is given by periodicityAndOffset. In the case where pur-ImplicitReleaseAfter is configured, for a PUR opportunity that occurs when the UE is in RRC_IDLE or RRC_INACTIVE, the UE may consider that the PUR opportunity is skipped if no transmission using the PUR is initiated or if a PUR failure indication is received from a lower layer. If a pur-ImplicitReleaseAfter number of consecutive PUR opportunities have been skipped, the UE may release the pur-Config, may discard the previously stored pur-Config, and / or may indicate to the lower layers that the pur-TimeAlignmentTimer is released if it is configured.

[0258] In the prior art, a base station (e.g., gNB, eNB) may receive an RRC request message with uplink data for small data transmission from a wireless device. The base station may retrieve the context of the wireless device and use the context to process the uplink data. In a base station functional split architecture, a base station distributed unit (DU) may release the context (e.g., RLC configuration, uplink tunnel information, etc.) of a wireless device that is in an RRC inactive state or an RRC idle state. If the base station DU receives uplink data for small data transmission from a wireless device that is in an RRC inactive state or an RRC idle state, the base station DU may need to receive the context of the wireless device from a base station central unit (CU). Depending on the network status, the base station CU may perform the small data transmission of the wireless device by initiating an RRC release procedure for the wireless device, or may transition the wireless device to an RRC connected state. In the example, as Fig.26As shown, when the base station DU receives the context of the wireless device and the base station CU intends to perform the RRC release procedure of the wireless device, the base station DU may misunderstand and may configure the configuration parameters of the RRC connection of the wireless device. Reserving configuration and resources for the wireless device that performs the RRC release procedure may increase resource waste and signaling complexity. In the example, when the base station DU receives the context of the wireless device and the base station CU intends to transition the wireless device to the RRC connection state, the base station DU may misunderstand and may not configure the configuration parameters of the RRC connection of the wireless device. The base station CU may need to perform another configuration procedure of the RRC connection of the wireless device with the base station DU. Performing multiple configuration procedures for the wireless device may increase signaling complexity and configuration latency. Existing protocols may increase the inefficiency of configuration signaling for wireless devices.

[0259] The exemplary embodiment can support the base station CU to send a message including the context of the wireless device to the base station DU, the message having a first indication indicating that the message is used for small data transmission or for the RRC connection of the wireless device and / or a second indication indicating that the context is used for uplink data associated with small data transmission. The first indication can be a field indicating small data transmission or RRC connection. The first indication can be the message itself (e.g., small data transmission request / response / configuration message or UE context establishment / modification message) of the small data transmission or RRC connection. Based on the first indication that the message is used for small data transmission or for the RRC connection of the wireless device, the base station DU may or may not configure the configuration parameters of the RRC connection of the wireless device. The second indication can indicate a separate configuration parameter of the uplink data associated with small data transmission. For example, the message can include a first configuration parameter of the context (e.g., the old context of the wireless device) containing uplink data and a second configuration parameter of the RRC connection of the wireless device. Based on the second indication that the context is used for uplink data associated with small data transmission and / or based on the separate configuration of uplink data and RRC connection, the base station DU can be configured for uplink data and RRC connection through a signal configuration program. The exemplary embodiment can increase signaling efficiency and reduce configuration waiting time.

[0260] The exemplary embodiment may support the base station CU to send a UE context release message including the context of the wireless device for small data transmission and an RRC release message of the wireless device to the base station DU. The base station DU may send uplink data associated with the small data transmission to the base station CU and based on the context, and transmit an RRC release message to the wireless device. The UE context release message including the context of the wireless device for small data transmission and the RRC release message may reduce the signaling of the configuration of the small data transmission. The exemplary embodiment may increase the signaling efficiency and reduce the configuration waiting time.

[0261] In the example, Fig.25 As shown, a wireless device (UE) can communicate with a base station (gNB) including a base station CU (gNB-CU) and / or one or more base station DUs. The one or more base station DUs may include a base station DU (gNB-DU). The base station CU may include a base station CU-CP (gNB-CU-CP) and a base station CU-UP (gNB-CU-UP). The wireless device may communicate directly with the base station DU via a wireless channel of one or more cells including a cell (cell 1). The wireless device may communicate with a base station CU (e.g., a base station CU-CP and / or a base station CU-UP) via one or more base station DUs including the base station DU.

[0262] In the example, the base station DU and the base station CU may be connected to each other via at least one F1 interface including an F1 control plane interface (F1-C) and / or an F1 user plane interface (F1-U). The base station DU may communicate with the base station CU-CP via the F1 control plane interface (F1-C). The base station DU may communicate with the base station CU-UP via the F1 user plane interface (F1-U). The base station CU-CP may communicate with the base station CU-UP via the E1 interface. In the example, the base station may include a plurality of base station DUs, the plurality of base station DUs including the base station DU and / or the second base station DU. The base station CU may communicate with the plurality of base station DUs via a plurality of F1 interfaces. The wireless device may communicate with the plurality of base station DUs. The wireless device may communicate with the base station CU via one or more base station DUs in the plurality of base station DUs. In the example, the base station DU or the second base station DU may provide a primary cell and / or a primary cell group for the wireless device. In an example, a base station (e.g., a base station CU, a base station CU-CP, and / or a base station CU-UP) may be connected to a core network node / device (e.g., a core network control plane: access and mobility management function (AMF), session management function (SMF), mobility management entity (MME); and / or a core network user plane: user plane function (UPF), serving gateway (S-GW)). In an example, a base station (e.g., a base station CU, a base station CU-CP, and / or a base station CU-UP) may be connected to at least one neighboring base station including a second base station (gNB2), for example, via an Xn interface or an X2 interface.

[0263] In the example, Fig.24 A flowchart showing an exemplary procedure of small data transmission (e.g., early data transmission) of a wireless device when a base station includes a base station DU and a base station CU, the base station CU may include a base station CU-CP and a base station CU-UP. Small data transmission (SDT) may be interpreted as at least one of EDT, MT-EDT, MO-EDT, uplink SDT, downlink SDT, etc.

[0264] In the example, Fig.28As shown, the base station DU may receive an RRC request message for a small data transmission (SDT) and uplink data associated with the small data transmission from the wireless device. The base station DU may send an RRC request message to the base station CU. Based on the RRC request message, the base station CU may retrieve a first context of the wireless device. Based on the RRC request message, the base station CU may determine to perform small data transmission of the wireless device. The base station DU may receive a configuration message from the base station CU, the configuration message including a first context of the wireless device and a first field indicating small data transmission. The base station DU may process / decode uplink data using the first context of the wireless device based on the first field. The base station DU may send the processed uplink data to the base station CU (e.g., the base station CU-UP). The base station DU may send a configuration response message in response to the configuration message to the base station CU (e.g., the base station CU-CP). The base station DU may receive an RRC response message (e.g., an RRC release message, an RRC early data completion message, etc.) from the base station CU for placing the wireless device in an RRC inactive state or an RRC idle state. The RRC response message may indicate that the wireless device is transitioning to an RC inactive state or an RRC idle state. The base station DU may send / forward / transmit an RRC response message. In an example, the base station DU may receive downlink data associated with a small data transmission from the base station CU. The base station DU may process the downlink data using the first context of the wireless device. The base station DU may send the processed downlink data to the wireless device.

[0265] In the example, Fig.29 As shown, based on receiving the RRC request message, the base station CU can determine to convert the wireless device to the RRC connection state and / or can determine to restore / set the RRC connection of the wireless device. For the RRC connection of the wireless device, the base station CU can send a configuration message to the base station DU, which includes a first context of the wireless device for uplink data and a second context of the RRC connection of the wireless device. The base station DU can use the first context to process the uplink data. The base station DU can use the first context to send uplink data (e.g., processed uplink data) to the base station CU (e.g., base station CU-UP). The base station DU can determine the configuration parameters of the RRC connection of the wireless device based on the second context. The base station DU can send a configuration response message including the configuration parameters determined based on the second context to the base station CU (e.g., base station CU-CP). The base station DU can receive an RRC message (e.g., an RRC recovery message, an RRC setting message, etc.) for the RRC connection from the base station CU. The RRC message may include the configuration parameters. The base station DU can send an RRC message to the wireless device. Based on the RRC message, the wireless device can be converted to the RRC connection state. The base station DU can communicate with the wireless device based on the configuration parameters.

[0266] In an example, a base station DU (e.g., a gNB-DU) may receive an RRC request message for a small data transmission (SDT) (e.g., early data transmission) and uplink data associated with the small data transmission from a wireless device.

[0267] In an example, the RRC request message may include at least one of the following: an RRC early data request message, an RRC recovery request message, an RRC setup request message, etc. In an example, the base station DU receiving the RRC request message from the wireless device may include at least one of the following: receiving the RRC request message based on a random access procedure of the wireless device; receiving the RRC request message via at least one preconfigured uplink resource (PUR), etc. In an example, the base station DU may receive at least one random access preamble of the random access procedure from the wireless device. The base station DU may send at least one random access response to the at least one random access preamble to the wireless device. The RRC request message may be based on at least one random access response. At least one random access preamble may be configured for small data transmission. In an example, the base station DU may receive an RRC request message with at least one random access preamble from the wireless device (e.g., for a 2-step random access procedure).

[0268] In an example, the base station DU may receive an RRC request message, uplink data, and / or at least one auxiliary parameter (e.g., release assistance information, RAI) indicating whether at least one subsequent data transmission is expected, etc. from the wireless device. The wireless device may send an RRC request message to the base station and / or the base station DU of the base station. The uplink data and / or at least one auxiliary parameter may be multiplexed and / or concatenated with the RRC request message. In an example, the wireless device may receive a paging message indicating a mobile terminated early data transmission (MT-EDT; e.g., mobile terminated small data transmission) from the base station DU. The wireless device may send an RRC request message for a small data transmission based on the paging message, for example, to receive downlink data associated with the MT-EDT.

[0269] In an example, the RRC request message may include at least one of the following: an RRC early data transfer request message, an RRC resume request message, an RRC setup request message, etc. In an example, the RRC request message may include at least one of a resume identifier (e.g., resumeIdentity, I-RNTI, shortI-RNTI), a resume MAC-I (e.g., resumeMAC-I, shortResumeMAC-I), a resume reason, an S-TMSI (e.g., a UE identifier, a NG-5G-S-TMSI), an establishment reason, NAS layer information (e.g., NAS PDU, DedicatedInfoNAS), etc. In an example, the resume identifier may include a UE identity to facilitate UE context retrieval for the wireless device at the base station. In an example, the resume MAC-I may include an authentication token to facilitate authentication of the wireless device at the base station (e.g., the 16 least significant bits of the MAC-I may be calculated based on the AS security configuration). In an example, the resume cause may include at least one of emergency, high priority access, mobile terminated access (mt-access), mobile originated signaling (mo-signaling), mobile originated data (mo-data), delay tolerant access, mobile originated voice call (mo-voice call), mobile terminated early data transfer (mt-EDT, MT SDT), mobile originated early data transfer (mo-EDT, MO SDT), RAN notification area update (ran-update), etc. The resume cause may provide the reason for the RRC resume request provided by the upper layer or the RRC layer. The network may not reject the RRCResumeRequest because the wireless device is using an unknown cause value. In an example, the establishment cause may include at least one of mobile originated data (mo-data), delay tolerant access, mobile terminated access (mt-access), etc. The establishment cause may provide the reason for the RRC early data request provided by the upper layer. The network may not reject the RRCEarlyDataRequest because the wireless device is using an unknown cause value.

[0270] In an example, a small data transmission may include data communication between a wireless device and a base station (e.g., and / or a core network, a data network, etc.) without converting the wireless device to an RRC connected state. In an example, a small data transmission may include transmission of at least one of the following: initial uplink data (e.g., uplink data), initial downlink data (e.g., downlink data associated with MT-EDT), at least one subsequent data of at least one subsequent data transmission indicated in at least one auxiliary parameter, at least one subsequent uplink data, at least one subsequent downlink data, etc. In an example, at least one subsequent data transmission may be associated with a small data transmission. At least one subsequent data transmission may include at least one subsequent uplink data transmission, at least one subsequent downlink data transmission, etc.

[0271] In an example, receiving the RRC request message by the base station DU may include receiving the RRC request message based on a random access procedure of the wireless device. In an example, the base station DU may receive at least one random access preamble of the random access procedure from the wireless device. The base station DU may send at least one random access response to the wireless device in response to the at least one random access preamble. The RRC request message may be based on the at least one random access response. The wireless device may transmit the RRC request message based on the at least one random access response.

[0272] In an example, at least one random access preamble of a random access process associated with the reception of an RRC request message may be configured for small data transmission. In an example, a base station DU may receive a configuration message from a base station CU (e.g., a base station CU-CP), the configuration message including at least one RA parameter indicating at least one random access preamble for small data transmission. The base station DU may transmit / broadcast a system information block indicating at least one random access preamble for small data transmission to multiple wireless devices including a wireless device via a cell of the base station DU. The system information block may include at least one RA parameter indicating at least one random access preamble for small data transmission. Receiving at least one random access preamble by the base station DU may be based on a system information block. The wireless device may receive at least one information block and / or may transmit at least one random access preamble based on a system information block. In an example, the wireless device may receive at least one RA parameter indicating at least one random access preamble via an RRC release message received by the wireless device when releasing / suspending a previous RRC connection. The wireless device may receive an RRC release message including at least one RA parameter from a base station and / or a base station DU of a base station.

[0273] In an example, receiving the RRC request message by the base station DU may include receiving the RRC request message via at least one preconfigured uplink resource (PUR). The wireless device may receive PUR configuration parameters of the at least one PUR via a system information block and / or a downlink RRC message (e.g., an RRC release message) from the base station and / or the base station DU of the base station. During the period when the wireless device is in an RRC idle state or an RRC inactive state, the wireless device may transmit the RRC request message, uplink data, and / or at least one auxiliary parameter via at least one PUR. The at least one PUR may include one or more periodic radio resources and / or a single time resource.

[0274] In an example, receiving at least one auxiliary parameter may include receiving at least one auxiliary parameter via at least one of: at least one medium access control control element (MAC CE), a physical uplink channel (e.g., PUSCH, PUCCH, uplink control information, UCI), at least one radio link control (RLC) packet header, etc. In an example, the wireless device may transmit the at least one auxiliary parameter to the base station DU via at least one MAC CE multiplexed and / or connected with an RRC message and / or uplink data.

[0275] In an example, at least one auxiliary parameter may include at least one of the following: a parameter indicating that no auxiliary information is released (e.g., no RAI); a parameter indicating that no subsequent downlink data transmission is expected; a parameter indicating that no subsequent uplink data transmission is expected; a parameter indicating that a single subsequent downlink data transmission is expected; a parameter indicating that a single subsequent uplink data transmission is expected; a first number of expected subsequent downlink data transmissions; a second number of expected subsequent uplink data transmissions; and the like.

[0276] In an example, at least one auxiliary parameter may include a buffer status report of the wireless device. The buffer status report may indicate the size of the data to be transmitted. The buffer status report may indicate the size of the data associated with the small data transmission, which may be buffered in at least one queue (e.g., MAC layer) of the wireless device. The buffer status report may include at least one logical channel identifier (LCID) of at least one logical channel and / or at least one logical channel group identifier (LCG ID) of at least one logical channel group. At least one logical channel and / or at least one logical channel group may be configured for data of the small data transmission. In an example, at least one auxiliary parameter may include at least one of the following: a bearer identifier of a bearer, a logical channel identifier of a logical channel, a logical channel group identifier of a logical channel group, a QoS flow identifier of a QoS flow, a session identifier of a PDU session, etc. Bearers, logical channels, logical channel groups, QoS flows, and PDU sessions may be configured for data associated with the small data transmission.

[0277] In an example, the base station DU may construct / determine at least one first information element (IE) of the auxiliary information based on at least one auxiliary parameter. The at least one first information element may indicate whether the wireless device expects at least one subsequent data transmission. The at least one first information element may be an information element of the F1 message. The at least one first information element may be at least one parameter of the GTP protocol layer. In an example, the at least one first information element may include at least one of the following: a parameter indicating that no auxiliary information is released; a parameter indicating that no subsequent downlink data transmission is expected; a parameter indicating that no subsequent uplink data transmission is expected; a parameter indicating that a single subsequent downlink data transmission is expected; a parameter indicating that a single subsequent uplink data transmission is expected; a first number of expected subsequent downlink data transmissions; a second number of expected subsequent uplink data transmissions, etc.

[0278] In an example, the base station DU may determine whether to initiate / request an RRC release procedure of the wireless device (e.g., to the base station CU) based on at least one auxiliary parameter. The base station DU may determine at least one second information element of the auxiliary information. The at least one second information element may indicate / request (e.g., to the base station CU) whether to initiate an RRC release procedure of the wireless device.

[0279] In an example, the base station DU may determine at least one second information element based on at least one auxiliary parameter received from the wireless device. In an example, if the at least one auxiliary parameter indicates one or more of no release auxiliary information, no subsequent downlink data transmission, no subsequent uplink data transmission, a single subsequent downlink data transmission, a single subsequent uplink data transmission, etc., the base station DU may determine to request / initiate an RRC release procedure for the wireless device, and / or the at least one second information element may indicate / request to perform an RRC release procedure for the wireless device. In an example, if the first number of subsequent downlink data transmissions and / or the second number of subsequent uplink data transmissions in the at least one auxiliary parameter is equal to or less than at least one threshold, the base station DU may determine to request / initiate an RRC release procedure for the wireless device, and / or the at least one second information element may indicate / request to perform an RRC release procedure for the wireless device. In an example, if the buffer status report in the at least one auxiliary parameter indicates that the data size is equal to or less than the threshold size value, the base station DU may determine to request / initiate an RRC release procedure for the wireless device, and / or the at least one second information element may indicate / request to perform an RRC release procedure for the wireless device.

[0280] In an example, the base station DU may determine at least one second information element based on at least one auxiliary parameter received from the wireless device. In an example, if the at least one auxiliary parameter indicates one or more of no release of auxiliary information, a single subsequent downlink data transmission, a single subsequent uplink data transmission, etc., the base station DU may determine to request / initiate a transition of the wireless device to an RRC connected state (e.g., not initiating an RRC release procedure of the wireless device) and / or the at least one second information element may indicate / request to transition the wireless device to an RRC connected state (e.g., not initiating an RRC release procedure of the wireless device). In an example, if the first number of subsequent downlink data transmissions and / or the second number of subsequent uplink data transmissions in the at least one auxiliary parameter is equal to or greater than at least one threshold, the base station DU may determine to request / initiate a transition of the wireless device to an RRC connected state (e.g., not initiating an RRC release procedure of the wireless device) and / or the at least one second information element may indicate / request to transition the wireless device to an RRC connected state (e.g., not initiating an RRC release procedure of the wireless device). In an example, the buffer status report in the at least one auxiliary parameter indicates that the data size is equal to or greater than the threshold size value, the base station DU can determine to request / initiate a transition of the wireless device to the RRC connected state (e.g., without initiating an RRC release procedure for the wireless device) and / or the at least one second information element can indicate / request to transition the wireless device to the RRC connected state (e.g., without initiating an RRC release procedure for the wireless device).

[0281] In an example, the base station DU may further determine at least one second information element based on a resource status of the base station DU and / or a cell of the base station DU. In an example, if the resource status of the base station DU and / or the cell (e.g., radio resource block usage rate, radio resource overload status, hardware overload status, etc.) is equal to or greater than a resource threshold, the base station DU may determine to request / initiate an RRC release procedure of the wireless device, and / or the at least one second information element may indicate / request to perform an RRC release procedure of the wireless device.

[0282] In an example, if the resource status of the base station DU and / or the cell (e.g., radio resource block usage rate, radio resource overload status, hardware overload status, etc.) is equal to or less than the resource threshold, the base station DU may determine to recommend / initiate a transition of the wireless device to the RRC connected state (e.g., without initiating an RRC release procedure for the wireless device) and / or at least one second information element may indicate / recommend transitioning the wireless device to the RRC connected state (e.g., without initiating an RRC release procedure for the wireless device) or may indicate an availability indication of a transition of the wireless device to the RRC connected state.

[0283] In an example, the base station DU may send an RRC request message to the base station CU (gNB-CU). In an example, sending the RRC request message by the base station DU to the base station CU may include sending the RRC request message to the base station CU-CP. In an example, the base station DU may send at least one message to the base station CU, the message including an RRC request message for small data transmission and / or auxiliary information for initiating an RRC release procedure for the wireless device. The base station CU may receive at least one message including an RRC request message for small data transmission from the wireless device and / or auxiliary information from the base station DU. The auxiliary information may be based on at least one auxiliary parameter. The auxiliary information may include at least one first information element indicating whether at least one subsequent data transmission is expected. The auxiliary information may include at least one second information element indicating / requesting / recommending whether to initiate an RRC release procedure for the wireless device (e.g., or whether to transition the wireless device to an RRC connected state).

[0284] In an example, receiving at least one message from the base station DU by the base station CU may include receiving at least one message via the F1 interface. The at least one message may include at least one of the following: an initial UL RRC message delivery message, a UL RRC message delivery message, a UE context modification / setting required message, a UE context setting / modification message, a notification message, an access success message, etc.

[0285] In an example, the at least one message may include at least one of the following: a wireless device identifier of the wireless device (e.g., gNB-DU UE F1AP ID, gNB-CU UE F1AP ID, TMSI, S-TMSI, C-RNTI, PUR-RNTI, IMSI, etc.), a cell identifier of a cell accessed by the wireless device for small data transmission (e.g., NR CGI, cell global identifier, physical cell identifier, etc.), an RRC container including an RRC request message, a DU to CU RRC container including cell configuration parameters and / or SRB / DRB configuration parameters configured for the wireless device, a supplementary uplink (SUL) access indication indicating whether the wireless device uses a supplementary uplink or a normal uplink to access the cell, a transaction identifier (e.g., transaction ID), a RAN UE ID, a second RRC container including an RRC setup / recovery complete message and / or an RRC release message (e.g., RRC-Container-RRCSetupComplete, RRC-Container-RRCResumeComplete, RRC-Container-RRCRelease), an SRB identifier of an SRB (e.g., SRB1 / 2 / 3), a PLMN identifier (e.g., a selected PLMN identifier), etc.

[0286] In an example, the auxiliary information of at least one message may include a buffer status report from a wireless device. The buffer status report may indicate the size of the data to be transmitted. The auxiliary information of at least one message may include an information element (e.g., SDT indication, EDT indication) indicating a small data transmission (e.g., MO-SDT, MO-EDT, MT-SDT, MT-EDT, etc.). The auxiliary information of at least one message may include a bearer identifier of a bearer (e.g., a logical channel, a QoS flow, a PDU session) associated with the small data transmission. In an example, the auxiliary information of at least one message may include at least one of the following: a bearer identifier of a bearer, a logical channel identifier of a logical channel, a logical channel group identifier of a logical channel group, a QoS flow identifier of a QoS flow, a session identifier of a PDU session, etc. The bearer, logical channel, logical channel group, QoS flow, PDU session may be configured for data associated with a small data transmission.

[0287] In an example, based on the RRC request message, the base station CU may retrieve the first context of the wireless device. The base station CU may retrieve the first context of the wireless device based on at least one identifier (e.g., in the RRC request message), the at least one identifier including at least one of a resume identifier (e.g., resumeIdentity, I-RNTI, shortI-RNTI), a resume MAC-I (e.g., resumeMAC-I, shortResumeMAC-I), an S-TMSI (e.g., a UE identifier, NG-5G-S-TMSI), etc. In an example, the base station CU may determine / identify an old base station of the wireless device (e.g., an anchor base station; a base station to which the wired device was previously connected). The base station CU may send a retrieve UE context request message including at least one identifier (e.g., resume identifier, resume MAC-I, S-TMSI, etc.) to the old base station. The old base station may retrieve the first context of the wireless device based on the retrieve UE context request message. The base station CU may receive a retrieve UE context response message (e.g., or a retrieve UE context failure message) including the first context of the wireless device from the old base station. In the example, based on the bearer identifier of the auxiliary information (e.g., and / or logical channel identifier, logical channel group identifier, QoS flow identifier, session identifier), the base station CU (e.g., and / or the old base station) can resume / establish / set the bearer of the wireless device (e.g., only the bearer among multiple suspended bearers of the wireless device; only the logical channel / logical channel group / QoS flow / PDU session among multiple logical channels, logical channel groups, QoS flows and / or PDU sessions of the wireless device).

[0288] In an example, based on the RRC request message, the base station CU may determine to perform a small data transmission of the wireless device. Determining to perform a small data transmission of the wireless device may be interpreted as determining to perform data reception and / or transmission with the wireless device without transitioning the wireless device to an RRC connected state. Determining to perform a small data transmission of the wireless device may be interpreted as determining to perform an RRC release procedure of the wireless device that sent the RRC request message.

[0289] In an example, the base station CU may determine whether to initiate an RRC release procedure of the wireless device (e.g., and / or whether to perform a small data transmission without transitioning the wireless device to an RRC connected state) based on at least one message (e.g., an RRC request message). In an example, based on the reception / transmission of uplink data, at least one subsequent uplink data, and / or at least one subsequent downlink data, the base station CU may determine whether to initiate an RRC release procedure of the wireless device. In an example, determining whether to initiate an RRC release procedure of the wireless device (e.g., whether to transition the wireless device to an RRC connected state; whether to perform an RRC connection recovery / setup procedure) may include determining based on the completion of a small data transmission (e.g., based on the completion of the transmission / reception of uplink data, at least one subsequent uplink data, and / or at least one subsequent downlink data). In an example, determining whether to initiate an RRC release procedure of the wireless device may include determining whether to transition the wireless device to an RRC connected state and / or determining whether to perform at least one of an RRC connection recovery / setup procedure of the wireless device. In an example, determining to initiate an RRC release procedure of the wireless device may include determining to transition the wireless device to an RRC inactive state or an RRC idle state. In an example, determining not to initiate an RRC release procedure for the wireless device may include determining to transition the wireless device to an RRC connected state and / or determining to perform an RRC connection recovery / setup procedure for the wireless device (e.g., by sending / transmitting an RRC recovery message and / or an RRC setup message to the wireless device).

[0290] In an example, determining whether to initiate an RRC release procedure for a wireless device may include at least one of the following: determining to initiate / execute an RRC release procedure based on auxiliary information indicating that subsequent downlink or uplink data transmission is not expected; determining to initiate an RRC release procedure based on auxiliary information indicating that a single subsequent downlink or uplink data transmission is expected; determining to transition the wireless device to an RRC connected state based on auxiliary information indicating that one or more subsequent downlink or uplink data transmissions are expected; and the like.

[0291] In an example, the base station CU may determine whether to initiate / perform an RRC release procedure of the wireless device (e.g., and / or whether to perform a small data transmission without transitioning the wireless device to an RRC connected state) based on auxiliary information (e.g., at least one first information element, at least one second information element, a buffer status report, etc.) received from the base station DU. In an example, if the at least one first information element indicates one or more of no release auxiliary information, no subsequent downlink data transmission, no subsequent uplink data transmission, a single subsequent downlink data transmission, a single subsequent uplink data transmission, etc., the base station CU may determine to initiate / perform an RRC release procedure of the wireless device and / or send / transmit an RRC release message to the wireless device for the RRC release procedure. In an example, if the first number of subsequent downlink data transmissions and / or the second number of subsequent uplink data transmissions in the at least one first information element is equal to or less than at least one threshold, the base station CU may determine to initiate / perform an RRC release procedure of the wireless device and / or send / transmit an RRC release message to the wireless device for the RRC release procedure. In an example, the buffer status report in the auxiliary information indicates that the data size is equal to or less than the threshold size value, and the base station CU may determine to initiate / perform the RRC release procedure of the wireless device and / or send / transmit an RRC release message to the wireless device for the RRC release procedure. In an example, if the at least one second information element indicates / requests to perform the RRC release procedure of the wireless device (e.g., and / or not to transition the wireless device to the RRC connected state), the base station CU may determine to initiate / perform the RRC release procedure of the wireless device and / or send / transmit an RRC release message to the wireless device for the RRC release procedure. In an example, the at least one second information element indicates that transitioning the wireless device to the RRC connected state is not available, and the base station CU may determine to initiate / perform the RRC release procedure of the wireless device and / or send / transmit an RRC release message to the wireless device for the RRC release procedure.

[0292] In an example, the base station CU may determine whether to initiate an RRC release procedure of the wireless device (e.g., and / or whether to perform a small data transmission without transitioning the wireless device to an RRC connected state) based on auxiliary information (e.g., at least one first information element, at least one second information element, a buffer status report, etc.) received from the base station DU. In an example, if the at least one first information element indicates one or more of no release of auxiliary information, a single subsequent downlink data transmission, a single subsequent uplink data transmission, etc., the base station CU may determine to transition the wireless device to an RRC connected state (e.g., not to initiate an RRC release procedure of the wireless device) and / or send / transmit an RRC recovery / setup message to the wireless device to transition the wireless device to an RRC connected state. In an example, if the first number of subsequent downlink data transmissions and / or the second number of subsequent uplink data transmissions in the at least one first information element is equal to or greater than at least one threshold, the base station CU may determine to transition the wireless device to an RRC connected state (e.g., not to initiate an RRC release procedure of the wireless device) and / or send / transmit an RRC recovery / setup message to the wireless device to transition the wireless device to an RRC connected state. In an example, the buffer status report in the assistance information indicates that the data size is equal to or greater than the threshold size value, and the base station CU may determine to transition the wireless device to the RRC connected state (e.g., without initiating an RRC release procedure of the wireless device) and / or send / transmit an RRC resume / setup message to the wireless device to transition the wireless device to the RRC connected state. In an example, if the at least one second information element indicates / requests not to perform the RRC release procedure of the wireless device (e.g., and / or transition the wireless device to the RRC connected state), the base station CU may determine to transition the wireless device to the RRC connected state (e.g., without initiating an RRC release procedure of the wireless device) and / or send / transmit an RRC resume / setup message to the wireless device to transition the wireless device to the RRC connected state. In an example, the at least one second information element indicates that transitioning the wireless device to the RRC connected state is available, and the base station CU may determine to transition the wireless device to the RRC connected state (e.g., without initiating an RRC release procedure of the wireless device) and / or send / transmit an RRC resume / setup message to the wireless device to transition the wireless device to the RRC connected state.

[0293] In an example, the base station CU may further determine whether to initiate / execute the RRC release procedure of the wireless device (e.g., and / or whether to perform small data transmission without transitioning the wireless device to an RRC connected state) based on the resource status of the base station CU, the base station DU, and / or the cell of the base station associated with the base station CU. In an example, if the resource status of the base station CU, the base station DU, and / or the cell of the base station associated with the base station CU (e.g., radio resource block usage rate, radio resource overload status, hardware overload status, etc.) is equal to or greater than the resource threshold, the base station CU may determine to initiate / execute the RRC release procedure of the wireless device and / or send / transmit an RRC release message to the wireless device for the RRC release procedure.

[0294] In an example, if the resource status of the cell of the base station CU, the base station DU and / or the base station associated with the base station CU (e.g., radio resource block utilization rate, radio resource overload status, hardware overload status, etc.) is equal to or less than the resource threshold, the base station CU can determine to transition the wireless device to the RRC connected state (e.g., without initiating the RRC release procedure of the wireless device) and / or send / transmit an RRC recovery / setup message to the wireless device to transition the wireless device to the RRC connected state.

[0295] In an example, the base station CU may send a configuration message to the base station DU, the configuration message including a first context of the wireless device and a first field indicating small data transmission. The base station DU may receive the configuration message from the base station CU. Based on a determination to perform a small data transmission of the wireless device (e.g., without transitioning the wireless device to an RRC connected state) and / or based on a determination to perform an RRC release procedure of the wireless device, the base station CU may send a configuration message including a first context of the wireless device and a first field indicating small data transmission to the base station DU.

[0296] In an example, in order to restore / establish a bearer (e.g., a logical channel, a logical channel group, a QoS flow, a PDU session), the base station CU may perform a UE context setup / modification procedure of the wireless device with the base station DU. For the UE context setup / modification procedure, the base station CU may send a context setup / modification request message including a bearer identifier of the bearer (e.g., and / or a logical channel identifier, a logical channel group identifier, a QoS flow identifier, a session identifier) ​​to the base station DU. In an example, the bearer and / or a logical channel associated with the bearer may be configured for small data transmission. Uplink data (e.g., data for small data transmission, subsequent uplink / downlink data) may be data of the bearer and / or the logical channel. In an example, the configuration message may include a context setup / modification request message.

[0297] In an example, a configuration message (e.g., a context setup / modification request message) may include at least one of the following: a wireless device identifier of the wireless device (e.g., gNB-DU UE F1AP ID, gNB-CU UE F1AP ID, TMSI, S-TMSI, C-RNTI, PUR-RNTI, IMSI, etc.), a cause parameter, an RRC container, a CU-to-DU RRC container including cell configuration parameters and / or SRB / DRB configuration parameters configured for the wireless device (e.g., QoS parameters, QoS flow identifier, S-NSSAI, network slice information, tunnel information, bearer identifier, etc.), a transaction identifier (e.g., transaction ID), a RAN UE ID, an SRB identifier of an SRB (e.g., SRB1 / 2 / 3), a PLMN identifier (e.g., a selected PLMN identifier), a list of candidate cells to be cancelled of the wireless device, an SpCell identifier of an SpCell of the wireless device, a serving cell identifier of the wireless device, DRX cycle information, a secondary cell identifier of a secondary cell of the wireless device, etc.

[0298] In an example, a first field of a configuration message may indicate that the configuration message (e.g., a context configuration / setting / modification procedure between a base station DU and a base station CU of a wireless device) is for small data transmission. The first field may indicate that the wireless device has not transitioned to an RRC connected state. The first field may indicate that the wireless device may perform an RRC release procedure. The base station DU may determine based on the first field that small data transmission is allowed / performed for the wireless device. The base station DU may determine based on the first field that the wireless device performs an RRC release procedure. Based on the first field indicating small data transmission, the base station DU may not configure the configuration parameters of the RRC connection of the wireless device. Based on the first field, the base station DU may use the first context of the wireless device to process uplink data.

[0299] In an example, the configuration message may include a second field indicating at least one of the following: the first context is used for uplink data (e.g., small data transmission, subsequent uplink / downlink data of the small data transmission); the first context is an old context of the wireless device, etc. The old context of the wireless device may be a context used by the wireless device and / or the network (e.g., an old base station) in previous communications with each other (e.g., when the wireless device was in a previous RRC connection state and / or when the wireless device performed a previous small data transmission, etc.). Based on the second field, the base station DU may use the first context of the wireless device to process the uplink data (e.g., and / or subsequent uplink / downlink data associated with the small data transmission) without modification.

[0300] In an example, the first context of the wireless device may include at least one of the following: RLC layer configuration parameters, uplink user plane transport layer information, etc. The uplink user plane transport layer information may include at least one of the following: a transport layer address (e.g., an IP address of a base station CU and / or a base station CU-UP), an uplink general packet radio service (GPRS) tunnel protocol (GTP) tunnel identifier, etc. The uplink user plane transport layer information may be configured for a bearer and / or logical channel associated with a small data transmission (e.g., uplink data and / or subsequent uplink / downlink data). The RLC configuration parameters may include parameters for at least one RLC mode in the RLC mode, the RLC mode including at least one of a transparent mode (TM) for uplink or downlink, an unacknowledged mode (UM) for uplink or downlink, an acknowledged mode (AM) for uplink or downlink, etc. The RLC configuration parameters may include sequence number configuration parameters. The RLC configuration parameters may be configured for a bearer and / or logical channel configuration associated with a small data transmission (e.g., uplink data and / or subsequent uplink / downlink data). In an example, sending the processed uplink data to the base station CU (eg, base station CU-UP) may include sending the processed uplink data to a transport layer address.

[0301] In an example, the base station DU may process / decode uplink data (e.g., and / or subsequent uplink / downlink data) using a first context of the wireless device based on the first field (e.g., and / or the second field). Processing / decoding uplink and / or subsequent uplink / downlink data may include decoding uplink data and / or subsequent uplink / downlink data using RLC configuration parameters. Processing / decoding uplink and / or subsequent uplink / downlink data may include decoding / converting at least one RLC PDU (e.g., MAC SDU) of uplink data and / or subsequent uplink / downlink data to at least one RLC SDU (e.g., PDCP PDU) of uplink data. Processing / decoding uplink and / or subsequent uplink / downlink data may include performing combination (e.g., desegmentation and / or reverse packet segmentation) of packets of uplink data and / or subsequent uplink / downlink data using RLC configuration parameters to produce / generate at least one PDCP PDU.

[0302] In an example, the base station DU may send processed uplink data (e.g., processed subsequent uplink data) to the base station CU (e.g., the base station CU-UP). Sending the processed uplink data by the base station DU to the base station CU may include sending the processed uplink data to the base station CU-UP. In an example, the base station DU may send the processed subsequent downlink data to the wireless device. Sending the processed subsequent downlink data by the base station DU to the wireless device may include sending the processed subsequent downlink data using a small data transmission. The base station DU may receive the subsequent downlink data from the base station CU and / or the base station CU-UP. The subsequent downlink data may be in response to the uplink data being sent by the wireless device.

[0303] In an example, the base station CU may receive and / or forward uplink data (e.g., processed uplink data) and / or subsequent uplink or downlink data (e.g., processed subsequent uplink data). In an example, the base station CU may receive uplink data associated with small data transmission from the wireless device and via the base station DU. The base station CU may transmit uplink data to a core network node (e.g., UPF, S-GW; in the case where the base station CU is an anchor base station of the wireless device and / or a central unit of an old base station) or a second base station (e.g., an anchor base station of the wireless device and / or an old base station).

[0304] In the example, the base station CU may receive subsequent downlink data associated with small data transmission from a core network node or a second base station. The base station CU may transmit subsequent downlink data to the wireless device via the base station DU. In the example, the subsequent downlink data may be response data for uplink data (e.g., from a device communicating with the wireless device). In the example, the base station CU may receive subsequent uplink data associated with small data transmission from the wireless device and via the base station DU (e.g., processed subsequent uplink data). The base station CU may transmit subsequent uplink data to the core network node or the second base station. In the example, the subsequent uplink data may be response data to subsequent downlink data (e.g., from a device communicating with the wireless device).

[0305] In an example, the base station CU may receive / transmit uplink data, subsequent uplink data, and / or subsequent downlink data from / to the base station DU via at least one tunnel between the base station CU and the base station DU (e.g., based on an uplink / downlink tunnel identifier). The base station CU may receive / transmit uplink data, subsequent uplink data, and / or subsequent downlink data from / to the core network node and / or the second base station via at least one tunnel between the base station CU and the core network node and / or between the base station CU and the second base station (e.g., based on an uplink / downlink tunnel identifier).

[0306] In an example, the base station DU may send a configuration response message in response to the configuration message to the base station CU (e.g., the base station CU-CP). Sending processed uplink data to the base station CU (e.g., the base station CU-CP) may include sending a configuration response message including processed uplink data via the F1 interface between the base station DU and the base station CU (e.g., the F1-C interface between the base station DU and the base station CU-CP). The configuration response message may include processed uplink data. The base station CU-CP may forward / send the processed uplink data to the base station CU-UP via one or more messages of the E1 interface between the base station CU-CP and the base station CU-UP. In an example, the base station CU (e.g., the base station CU-CP) may receive a confirmation message from the base station DU and in response to the context setup / modification request message, which indicates the completion of the restoration / establishment of the bearer (e.g., logical channel, logical channel group, QoS flow, PDU session). The configuration response message in response to the configuration may include a confirmation message.

[0307] In an example, the base station DU may determine / update the suspension configuration parameters of the wireless device based on the first field of the configuration message indicating the small data transmission. The suspension configuration parameters may be used by the wireless device in an RRC inactive state or an RRC idle state. In an example, the configuration response message may include the suspension configuration parameters. The suspension configuration parameters may include at least one of the following: parameters of a preconfigured uplink resource (PUR), random access parameters for small data transmission, etc. The PUR may be interpreted as a configured grant (CG) used by the wireless device in an RRC inactive state and / or an RRC idle state. The PUR (e.g., CG) may be configured for a bearer and / or logical channel associated with small data transmission (e.g., allowed to use small data transmission). The suspension configuration parameters may include one or more cell identifiers of one or more cells configured with the PUR (e.g., CG). The parameters of the PUR may include at least one of the following: periodicity, timing offset, size, etc. The random access parameters may include at least one of the following: parameters indicating a preamble, resource parameters for transmission of the preamble, etc.

[0308] In an example, the base station CU may construct an RRC response message (e.g., an RRC release message, an RRC early data complete message, etc.) of the wireless device. The RRC response message may be used for an RRC release procedure of the wireless device. The RRC response message may indicate that the wireless device stays in an RRC inactive state or an RRC idle state. The RRC response message may indicate that the wireless device transitions to an RC inactive state or an RRC idle state. The RRC response message may include a suspension configuration parameter.

[0309] In an example, the base station DU may receive an RRC response message from the base station CU that the wireless device is in an RRC inactive state or an RRC idle state. In an example, based on determining to initiate an RRC release procedure, the base station CU may send an RRC response message to the wireless device (e.g., an RRC release message of the RRC release procedure and / or an RRC early data completion message of completion of a small data transmission). The base station CU may send / transmit a context message to the base station DU, the context message including an RRC response message for placing the wireless device in an RRC inactive state and / or an RRC idle state. The base station DU may receive a context message including an RRC response message of the wireless device from the base station CU. In an example, if the base station CU determines to initiate an RRC release procedure (e.g., without transitioning the wireless device to an RRC connected state), the base station CU may transmit / send an RRC release message to the wireless device via a context message and / or via the base station DU.

[0310] In an example, sending / transmitting a context message by the base station CU to the base station DU may include sending / transmitting a context message via an F1 interface. In an example, the context message may include at least one of the following: a UE context release command message, a DL RRC message transfer message, a UE context modification / setting request message, a UE context setting / modification completion message, a notification message, an access success message, etc.

[0311] In an example, the context message may include at least one of the following: a wireless device identifier of the wireless device (e.g., gNB-DU UE F1AP ID, gNB-CU UE F1AP ID, TMSI, S-TMSI, C-RNTI, PUR-RNTI, IMSI, etc.), a cause parameter (e.g., a reason for performing an RRC release procedure), an RRC container including an RRC response message (e.g., an RRC release message of an RRC release procedure and / or an RRC early data complete message of completion of a small data transfer), a CU to DU RRC container including cell configuration parameters and / or SRB / DRB configuration parameters configured for the wireless device (e.g., QoS parameters, QoS flow identifier, S-NSSAI, network slice information, tunnel information, bearer identifier, etc.), a transaction identifier (e.g., transaction ID), a RAN UE The context message may include a UE context release command message, an RRC response message, an RRC response message, and a UE context release command message. The context message may include an RRC response message, an RRC response message, and a UE context release command message. The context message may include an RRC response message, an RRC response message, and a UE context release command message. The context message may include an RRC response message, an RRC response message, and a UE context release command message.

[0312] In an example, the RRC release message may include a list of at least one bearer (e.g., SRB, DRB) that may be allowed to use a procedure for small data transmission (e.g., early data transmission). Based on the list of at least one bearer, if the wireless device has data associated with the at least one bearer when the wireless device is in the RRC inactive state or the RRC idle state, the wireless device may perform the small data transmission.

[0313] In an example, the base station DU may send / forward / transmit an RRC response message to the wireless device. In an example, based on receiving an RRC release message from the base station DU and / or the base station CU, the wireless device may be in an RRC idle state or an RRC inactive state.

[0314] In an example, the base station DU may transmit / send the initial downlink data and / or at least one subsequent downlink data to the wireless device by multiplexing and / or connecting the initial downlink data and / or at least one subsequent downlink data with an RRC release message or an RRC message.

[0315] In an example, the base station DU may receive downlink data associated with a small data transmission from the base station CU. The base station DU may process the downlink data using the first context of the wireless device. The base station DU may send the processed downlink data to the wireless device.

[0316] In an example, based on receiving the RRC request message, the base station CU may determine to transition the wireless device to the RRC connection state and / or may determine to restore / set the RRC connection of the wireless device. The base station CU may determine to transition the wireless device to the RRC connection state based on the auxiliary information and / or one or more reasons. The one or more reasons may include at least one of the following: reconfiguring the wireless device (e.g., NAS layer reconfiguration, RRC layer reconfiguration, security reconfiguration, etc.), the size of the uplink data and / or at least one subsequent data is greater than a threshold size value, the resources of the base station are not congested, the remaining battery of the wireless device is greater than a threshold (e.g., the RRC request message may include an indication field indicating the remaining battery, such as low / medium / high and / or full), etc. The base station CU may determine to transition the wireless device to the RRC connection state based on uncertainty not to perform / initiate the RRC release procedure of the wireless device.

[0317] In an example, for the RRC connection of the wireless device, the base station CU may send a second configuration message to the base station DU, the second configuration message including a first context of the wireless device for uplink data and a second context of the RRC connection of the wireless device. The base station DU may receive the second configuration message including the first context and the second context.

[0318] In an example, the second configuration message may include a field indicating at least one of the following: small data transmission is not performed; the wireless device transitions to an RRC connected state, etc. In an example, the second configuration message may include a second field indicating at least one of the following: the first context is used for uplink data; the first context is an old context of the wireless device, etc. The field indicating that the wireless device transitions to an RRC connected state may be a first field indicating small data transmission (e.g., a first field with a value of "0" may indicate that the wireless device transitions to an RRC connected state; a first field with a value of "0" may indicate small data transmission). The second configuration message may be a configuration message that may be used to indicate small data transmission of the wireless device.

[0319] In an example, the first context of the wireless device may include at least one of the following: RLC layer configuration parameters, uplink user plane transport layer information, etc. The RLC configuration parameters may include parameters for at least one of the RLC modes, the RLC mode including at least one of a transparent mode (TM) for uplink or downlink, an unacknowledged mode (UM) for uplink or downlink, an acknowledged mode (AM) for uplink or downlink, etc. The RLC configuration parameters may include sequence number configuration parameters. The uplink user plane transport layer information may include at least one of the following: a transport layer address, an uplink GTP tunnel identifier, etc.

[0320] In an example, the second context of the RRC connection of the wireless device may include updated configuration parameters of the first context of the wireless device. The base station DU may use the second context to communicate with the wireless device in the RRC connected state (e.g., after the wireless device transitions to the RRC connected state).

[0321] In an example, the base station DU may use the first context to process uplink data (e.g., and / or at least one subsequent data, at least one subsequent uplink data, etc.). In an example, the base station DU may use the first context to send uplink data (e.g., processed uplink data) to the base station CU (e.g., base station CU-UP). Sending uplink data by the base station DU to the base station CU may include sending processed uplink data. In an example, sending uplink data by the base station DU to the base station CU may include sending uplink data to a transport layer address (e.g., uplink user plane transport layer information in the first context of the configuration message). The base station DU may use the first context to send at least one subsequent data (e.g., at least one downlink data) received from the base station CU (e.g., base station CU-UP) to the wireless device. The base station DU may process at least one subsequent data (e.g., at least one downlink data) based on the first context. Sending at least one subsequent data by the base station DU to the wireless device may include sending at least one processed subsequent data.

[0322] In an example, the base station DU may determine configuration parameters of the RRC connection of the wireless device based on the second context. The wireless device may use the configuration parameters after transitioning to the RRC connected state. In an example, the base station DU may send a configuration response message including the configuration parameters determined based on the second context to the base station CU (e.g., base station CU-CP).

[0323] In an example, the base station DU may receive an RRC message (e.g., an RRC resume message, an RRC setup message, etc.) of an RRC connection of the wireless device from the base station CU. The base station CU may construct the RRC message based on the configuration parameters in the configuration response message. The RRC message may include the configuration parameters. In an example, if the base station CU determines not to initiate an RRC release procedure (e.g., transitioning the wireless device to an RRC connected state), the base station CU may transmit / send an RRC release message (e.g., an RRC resume message, an RRC setup message, etc.) to the wireless device via a context message and / or via the base station DU.

[0324] In an example, the base station DU may send an RRC message to the wireless device. In an example, based on the RRC message, the wireless device may transition to an RRC connected state. In an example, in response to receiving an RRC message from the base station DU and / or the base station CU, the wireless device may send / transmit an RRC complete message. The wireless device may transition to an RRC connected state (e.g., establish / restore / set an RRC connection with a base station) based on an RRC message from the base station DU and / or the base station CU. The RRC complete message may include at least one of an RRC setup complete message, an RRC recovery complete message, and the like.

[0325] In an example, the base station DU may communicate with the wireless device based on the configuration parameters. The base station DU may transmit a transport block to the wireless device in the RRC connected state based on the configuration parameters. The base station DU may receive a transport block from the wireless device in the RRC connected state based on the configuration parameters.

[0326] In the example, Fig.30 As shown, the base station DU may receive an RRC request message for a small data transmission and uplink data associated with the small data transmission from the wireless device. The base station DU may send an RRC request message to the base station CU. The base station DU may receive a message including an RRC response message of the wireless device and a first context of the wireless device from the base station CU. The base station DU may send uplink data based on the first context of the wireless device to the base station CU. The base station DU may send an RRC response message to the wireless device. In the example, the message including the RRC response message and the first context may include a configuration message from the base station CU to the base station DU via the F1 interface.

[0327] In an example, the RRC response message may include at least one of the following: an RRC release message, an RRC early data complete message, etc. The RRC response message may indicate that the wireless device transitions to an RC inactive state or an RRC idle state. The RRC response message may indicate that the wireless device stays / maintains in an RRC inactive state or an RRC idle state. In an example, the base station DU may transmit subsequent uplink or downlink data associated with a small data transmission with the wireless device and / or the base station CU based on the first context of the wireless device.

[0328] In an example, the first context of the wireless device may include at least one of the following: RLC layer configuration parameters, uplink user plane transport layer information, etc. The RLC configuration parameters may include parameters for at least one of the RLC modes, the RLC mode including at least one of a transparent mode (TM) for uplink or downlink, an unacknowledged mode (UM) for uplink or downlink, an acknowledged mode (AM) for uplink or downlink, etc. The RLC configuration parameters may include sequence number configuration parameters. The uplink user plane transport layer information may include at least one of the following: a transport layer address, an uplink GTP tunnel identifier, etc.

[0329] In the example, Fig.28 , Fig.31 and / or Fig.32 As shown, the base station DU can receive an RRC request message for a small data transmission (SDT) and uplink data associated with the small data transmission from the wireless device. The base station DU can send an RRC request message to the base station CU. The base station DU can receive a configuration message from the base station CU, the configuration message including a first context of the wireless device and a first field indicating the small data transmission. The base station DU can process / decode the uplink data using the first context of the wireless device based on the first field. The base station DU can send the processed uplink data to the base station CU.

[0330] In an example, the first field may indicate that the configuration message is for small data transmission. The first field may indicate that the wireless device has not transitioned to an RRC connected state. The base station DU may determine based on the first field that small data transmission is allowed / performed for the wireless device. The base station DU may determine based on the first field that the wireless device performs an RRC release procedure. Based on the first field indicating small data transmission, the base station DU may not configure configuration parameters for the RRC connection of the wireless device.

[0331] In an example, the configuration message may include a second field indicating at least one of the following: the first context is used for uplink data; the first context is an old context of the wireless device. Based on the second field, the base station DU may use the first context of the wireless device to process the uplink data without modification.

[0332] In an example, the base station DU may send a configuration response message in response to the configuration message to the base station CU. Sending the processed uplink data to the base station CU may include sending a configuration response message including the processed uplink data. In an example, the configuration response message may include a pause configuration parameter based on the first field. The pause configuration parameter may be used by the wireless device in an RRC inactive state or an RRC idle state. The pause configuration parameter may include at least one of the following: parameters of a preconfigured uplink resource (PUR), random access parameters for small data transmission, etc. The parameters of the PUR may include at least one of the following: periodicity, timing offset, size, etc. The random access parameter may include at least one of the following: parameters indicating a preamble, resource parameters for transmission of the preamble, etc.

[0333] In an example, the first context of the wireless device may include at least one of the following: a radio link control (RLC) layer configuration parameter, an uplink user plane transport layer information, etc. The uplink user plane transport layer information may include at least one of the following: a transport layer address (e.g., an IP address of a base station CU and / or a base station CU-UP), an uplink general packet radio service (GPRS) tunneling protocol (GTP) tunnel identifier, etc. The RLC configuration parameter may include a parameter for at least one of the RLC modes, the RLC mode including at least one of a transparent mode (TM) for uplink or downlink, an unacknowledged mode (UM) for uplink or downlink, an acknowledged mode (AM) for uplink or downlink, etc. The RLC configuration parameter may include a sequence number configuration parameter. In an example, sending the processed uplink data to the base station CU may include sending the processed uplink data to the transport layer address.

[0334] In an example, the base station DU may receive an RRC response message from the base station CU that the wireless device is in an RRC inactive state or an RRC idle state. The RRC response message may indicate that the wireless device is transitioning to an RC inactive state or an RRC idle state. The base station DU may send / forward / transmit the RRC response message. The RRC response message may include a suspension configuration parameter used by the wireless device in the RRC inactive state or the RRC idle state. The RRC response message may include at least one of the following: an RRC release message, an RRC early data completion message, etc.

[0335] In an example, the base station DU may receive downlink data associated with a small data transmission from the base station CU. The base station DU may process the downlink data using the first context of the wireless device. The base station DU may send the processed downlink data to the wireless device.

[0336] In an example, the RRC request message may include at least one of the following: an RRC early data request message, an RRC recovery request message, an RRC setup request message, etc. In an example, the base station DU receiving the RRC request message from the wireless device may include at least one of the following: receiving the RRC request message based on a random access procedure of the wireless device; receiving the RRC request message via at least one preconfigured uplink resource (PUR), etc. In an example, the base station DU may receive at least one random access preamble of the random access procedure from the wireless device. The base station DU may send at least one random access response to the at least one random access preamble to the wireless device. The RRC request message may be based on at least one random access response. At least one random access preamble may be configured for small data transmission. In an example, the base station DU may receive an RRC request message with at least one random access preamble from the wireless device (e.g., for a 2-step random access procedure).

[0337] In an example, sending an RRC request message by the base station DU to the base station CU may include sending an RRC request message to the base station CU-CP. Sending processed uplink data by the base station DU to the base station CU may include sending processed uplink data to the base station CU-UP. The base station CU may include a base station CU-CP and a base station CU-UP. The base station may include a base station DU and a base station CU. In an example, the small data transmission may include data communication between a wireless device and a base station (e.g., and / or a core network, a data network, etc.) without converting the wireless device to an RRC connected state.

[0338] In the example, Fig.29 , Fig.31 and / or Fig.32 As shown, the base station DU can receive an RRC request message for small data transmission and uplink data associated with the small data transmission from the wireless device. The base station DU can send an RRC request message to the base station CU. The base station DU can receive a configuration message from the base station CU, which includes a first context of the wireless device for uplink data and a second context of the RRC connection of the wireless device. The base station DU can use the first context to send uplink data to the base station CU, and can send a configuration response message including configuration parameters determined based on the second context to the base station CU.

[0339] In an example, the base station DU may process the uplink data using the first context. Sending the uplink data by the base station DU to the base station CU may include sending the processed uplink data. The base station DU may determine the configuration parameter based on the second context.

[0340] In an example, the base station DU may receive an RRC response message of the RRC connection from the base station CU. The RRC response message may include configuration parameters. The base station DU may send an RRC response message to the wireless device. The RRC response message may include at least one of the following: an RRC recovery message, an RRC setup message, etc.

[0341] In an example, the configuration message may include a first field indicating at least one of the following: small data transmission is not performed; the wireless device transitions to an RRC connected state, etc. In an example, the configuration message may include a second field indicating at least one of the following: the first context is used for uplink data; the first context is an old context of the wireless device, etc.

[0342] In an example, the first context of the wireless device may include at least one of the following: RLC layer configuration parameters, uplink user plane transport layer information, etc. The RLC configuration parameters may include parameters for at least one of the RLC modes, the RLC mode including at least one of a transparent mode (TM) for uplink or downlink, an unacknowledged mode (UM) for uplink or downlink, an acknowledged mode (AM) for uplink or downlink, etc. The RLC configuration parameters may include sequence number configuration parameters. The uplink user plane transport layer information may include at least one of the following: a transport layer address, an uplink GTP tunnel identifier, etc.

[0343] In an example, sending the uplink data by the base station DU to the base station CU may include sending the uplink data to a transport layer address.

[0344] In the example, Fig.30 As shown, the base station DU may receive an RRC request message for small data transmission and uplink data associated with the small data transmission from the wireless device. The base station DU may send an RRC request message to the base station CU. The base station DU may receive an RRC response message including an RRC response message of the wireless device and a message of the first context of the wireless device from the base station CU. The base station DU may send uplink data based on the first context of the wireless device to the base station CU. The base station DU may send an RRC response message to the wireless device.

[0345] In an example, the first context of the wireless device may include at least one of the following: RLC layer configuration parameters, uplink user plane transport layer information, etc. The RLC configuration parameters may include parameters for at least one of the RLC modes, the RLC mode including at least one of a transparent mode (TM) for uplink or downlink, an unacknowledged mode (UM) for uplink or downlink, an acknowledged mode (AM) for uplink or downlink, etc. The RLC configuration parameters may include sequence number configuration parameters. The uplink user plane transport layer information may include at least one of the following: a transport layer address, an uplink GTP tunnel identifier, etc.

[0346] In an example, the RRC response message may include at least one of the following: an RRC release message, an RRC early data complete message, etc. The RRC response message may indicate that the wireless device transitions to an RC inactive state or an RRC idle state. In an example, the base station DU may transmit subsequent uplink or downlink data associated with the small data transmission with the wireless device and / or the base station CU based on the first context of the wireless device.

Claims

1. A base station distributed unit, comprising: one or more processors; as well as A memory storing a computer program, when the computer program is executed by the one or more processors, causes the base station distributed unit to perform operations including the following: Received from a wireless device that is not in a Radio Resource Control (RRC) Connected state: RRC request message for small data transmission SDT procedure; as well as Uplink data associated with SDT procedures; Sending an RRC request message of the SDT procedure to a base station central unit; Receive a message from the base station central unit, the message comprising: Radio Link Control (RLC) configuration parameters of the SDT procedure; as well as A field indicating that the RLC configuration parameter is used for the SDT procedure; as well as The uplink data is sent to the base station central unit according to the field.

2. The base station distributed unit of claim 1, wherein sending the RRC request message to the base station central unit is based on receiving the RRC request message from the wireless device.

3. The base station distributed unit according to claim 1, wherein: The RRC request message is sent via an uplink F1 message, and the uplink F1 message includes an initial uplink UL RRC message delivery message or a user equipment UE context modification required message.

4. The base station distributed unit according to claim 1, wherein the field indicates: The wireless device does not transition to an RRC connected state; allowing the SDT procedure for the wireless device; and The wireless device performs an RRC release procedure.

5. The base station distributed unit of claim 1, the operations further comprising determining, based on a field indicating the SDT procedure, that the wireless device uses the SDT procedure and transmits the uplink data.

6. The base station distributed unit according to claim 1, wherein: The SDT procedure includes communicating data with the wireless device without transitioning the wireless device to the RRC connected state.

7. The base station distributed unit of claim 1, wherein the operation further comprises sending, by the base station distributed unit, an RRC response message to the wireless device indicating that the wireless device is not in the RRC connected state.

8. The base station distributed unit according to claim 7, wherein: The RRC response message includes suspension configuration parameters that are not used by the wireless device in the RRC connected state.

9. The base station distributed unit according to claim 7, wherein the RRC response message comprises an RRC release message or an RRC early data complete message.

10. The base station distributed unit according to claim 1, wherein: The message including a field indicating that the RLC configuration parameter is for the SDT procedure also includes a context of the wireless device.

11. A base station central unit, comprising: one or more processors; as well as a memory storing a computer program which, when executed by the one or more processors, causes the base station central unit to perform operations comprising: receiving a radio resource control RRC request message of a small data transmission SDT procedure from a base station distributed unit; The base station central unit sends a message to the base station distributed unit, the message including: Radio Link Control RLC configuration parameters for SDT procedures; as well as A field indicating that RLC configuration parameters are used for the SDT procedure; as well as Uplink data associated with the SDT procedure is received by the base station central unit from the base station distributed unit.

12. The base station central unit of claim 11, wherein receiving the RRC request message precedes sending by the base station central unit a message indicating the SDT procedure.

13. The base station central unit of claim 11, wherein receiving the RRC request message is performed via an uplink F1 message, the uplink F1 message comprising an initial uplink (UL) RRC messaging message or a user equipment (UE) context modification required message.

14. The base station central unit of claim 11, wherein said field indicates: The wireless device does not transition to the RRC connected state; allowing the SDT procedure for the wireless device; and The wireless device performs an RRC release procedure.

15. The base station central unit of claim 11, further comprising determining, based on a field indicating the SDT procedure, that the wireless device uses the SDT procedure and transmits the uplink data.

16. The base station central unit according to claim 11, wherein: The SDT procedure includes communicating data with a wireless device without transitioning the wireless device to an RRC connected state.

17. The base station central unit of claim 11, wherein the SDT procedure is an SDT procedure of a wireless device.

18. The base station central unit according to claim 11, wherein: The message including a field indicating that RLC configuration parameters are used for the SDT procedure also includes a context of the wireless device.

19. The base station central unit of claim 11, wherein the field indicates that an SDT procedure is allowed for the wireless device.

20. A non-transitory computer readable medium comprising a computer program, which, when executed by one or more processors, causes one or more processors of a base station distributed unit to perform operations comprising: Received from a wireless device that is not in a Radio Resource Control (RRC) Connected state: RRC request message for small data transmission SDT procedure; as well as Uplink data associated with SDT procedures; Sending an RRC request message of the SDT procedure to a base station central unit; Receive a message from the base station central unit, the message comprising: Radio Link Control RLC configuration parameters of the SDT procedure; as well as A field indicating that RLC configuration parameters are used for the SDT procedure; as well as The uplink data is sent to the base station central unit based on the field.

Images