Base station signaling for direct transmission by user equipment during inactivity

Abstract

Systems, methods, and circuits for direct transmission of uplink data using a contention-free random access (CFRA) procedure by an inactive UE are provided. In one example, the method includes: when a user equipment (UE) device is in a radio resource control (RRC) inactive state, receiving uplink data transmitted by the UE, wherein the UE uses a contention-free random access (CFRA) procedure to transmit the uplink data using a dedicated physical random access channel (PRACH) resource or a dedicated preamble resource (dedicated PRACH / preamble resource) assigned to the UE by a network.

Description

Background Art

[0001] The Random Access Channel (RACH) procedure is used by a User Equipment (UE) to establish synchronization with a base station and to obtain a network identifier and resources for transmission of uplink data. Summary of the invention

[0002] One aspect of the present disclosure relates to an apparatus for a base station, comprising a memory and one or more processors coupled to the memory, wherein the one or more processors are configured to cause the base station, when executing instructions stored in the memory: broadcast a message indicating that a first cell associated with the base station supports direct uplink transmission from a user equipment UE in a radio resource control (RRC) inactive state; receive a physical random access channel (PRACH) preamble on a preamble resource from the UE during a contention-free random access (CFRA) procedure with the first cell, wherein the PRACH preamble or preamble resource is assigned to the UE by a network via signaling from a second cell different from the first cell to the UE for performing direct uplink transmission without entering an RRC connected state; and receive uplink data from the UE when the UE is in an RRC inactive state during the CFRA procedure.

[0003] Another aspect of the present disclosure relates to a method for wireless communication, comprising: broadcasting a message indicating that a first cell associated with the base station supports direct uplink transmission from a user equipment UE in a radio resource control (RRC) inactive state; receiving a physical random access channel (PRACH) preamble on a preamble resource from the UE during a contention-free random access (CFRA) procedure with the first cell, wherein the PRACH preamble or preamble resource is assigned to the UE by a network via signaling from a second cell different from the first cell to the UE for performing direct uplink transmission without entering an RRC connected state; and receiving uplink data from the UE when the UE is in an RRC inactive state during the CFRA procedure. BRIEF DESCRIPTION OF THE DRAWINGS

[0004] Some examples of circuits, devices and / or methods will be described below by way of example only.In this context, reference will be made to the accompanying drawings.

[0005] Figure 1 is a state diagram of UE Radio Resource Control (RRC) states.

[0006] Figure 2 is a flow chart of an exemplary RRC recovery procedure.

[0007] Figure 3Ais a flow chart of an exemplary four-step RACH procedure employed by a UE to perform the RRC recovery procedure of FIG. 4 .

[0008] Figure 3B is a flow chart of an exemplary two-step RACH procedure employed by a UE to perform the RRC recovery procedure of FIG. 4 .

[0009] Figure 4A is a flow chart illustrating the delay between data arrival at a UE in an inactive state and data transmission by the UE after transitioning to a connected state.

[0010] Figure 4B is a flow chart illustrating reduced latency between arrival of data at a UE in an inactive state and data transmission by the UE remaining in the inactive state.

[0011] Figure 5A and Figure 5B is a flow chart illustrating direct uplink transmission via a contention-free random access (CFRA) procedure by an inactive UE in accordance with various aspects disclosed.

[0012] Figure 6 is a flow chart illustrating direct uplink transmission via CFRA using a resource availability indication identifier by an inactive UE in accordance with various aspects disclosed.

[0013] Figure 7 is a flow chart illustrating direct uplink transmissions by an inactive UE with various cells in a network in accordance with various aspects disclosed.

[0014] Figure 8 is a flow chart illustrating direct uplink transmission via CFRA using a timer by an inactive UE in accordance with various aspects disclosed.

[0015] Fig.9A and Fig. 9B is a flow chart illustrating direct uplink transmission via four-step CFRA by an inactive UE in accordance with various aspects disclosed.

[0016] Fig. 10A and Fig. 10B is a flow chart illustrating direct uplink transmission via two-step CFRA by an inactive UE in accordance with various aspects disclosed.

[0017] Fig.11 is a flow chart illustrating an example method for performing direct uplink transmission via CFRA by an inactive UE in accordance with various aspects disclosed.

[0018] Fig.12An exemplary communication network in accordance with various aspects disclosed is shown.

[0019] Fig.13 Examples of infrastructure equipment devices (e.g., BS, eNB, gNB) according to various aspects disclosed are shown.

[0020] Fig.14 An example of a user equipment device (eg, UE) in accordance with various aspects disclosed is shown. DETAILED DESCRIPTION

[0021] The present disclosure is described with reference to the accompanying drawings. The accompanying drawings are not drawn to scale, and these drawings are provided only for illustrating the present disclosure. Several aspects of the present disclosure are described below with reference to example applications for illustration. Many specific details, relationships and methods are set forth to provide an understanding of the present disclosure. The present disclosure is not limited by the order of the actions or events illustrated, because some actions can occur in different orders and / or simultaneously with other actions or events. In addition, not all illustrated actions or events are necessary to implement the method according to the selected present disclosure.

[0022] Figure 1 1 is a state diagram showing three radio resource control (RRC) states in which a UE may operate. In the idle state, the UE is disconnected from the core network (CN). When in the idle state, the UE performs cell reselection and may receive paging messages from the CN by means of the cell on which the UE is camping. To enter the connected state, the UE performs an RRC connection procedure 110, in which the UE connects to the CN and the radio access network (RAN) using a random access channel (RACH) procedure (described in more detail below). In the connected state, the UE connects to the CN and registers with it. A control and user plane connection is established between the RAN and the CN for the UE. The RAN knows which cell the UE belongs to, and all parameters required for unicast communication between the UE and the RAN are known to both the UE and the RAN. The UE context including the UE's access stratum (AS) context (e.g., the UE's cell radio network temporary identity (C-RNTI) and the cell identity of the primary cell) and the RRC configuration for the UE (e.g., radio bearers and security information) are stored in the RAN and also in the UE.

[0023] The UE may return from the connected state to the idle state by performing an RRC release procedure 120. When the UE returns to the idle state, the UE context is deleted from the UE and the RAN. The UE may also enter the idle state from the connected state or the inactive state by default when no cell can be found for camping, as indicated by 130, 160 respectively.

[0024] The inactive state is introduced in 5G to provide an intermediate state between the idle state and the connected state that will speed up the reconnection process by eliminating some of the signaling used to transition from the idle state to the connected state. The inactive state is beneficial for UEs that do not communicate with the RAN frequently, and achieves power savings compared to these UEs that remain in the connected state. To enter the inactive state, the UE performs an RRC suspend procedure 140, where the UE context is stored by both the UE and the serving gNB, and an RRC release procedure occurs subsequently. In the inactive state, the UE still has a non-access stratum (NAS) connection with the CN (i.e., still in a connection management (CM) connected state, as opposed to the idle state where the UE is not a CM connected).

[0025] When in the inactive state, the UE can move within the RAN Notification Area (RNA) without notifying the RAN, perform cell reselection, and receive paging messages from the RAN. However, the UE does not have dedicated AS resources for performing unicast communications, and therefore cannot perform any dedicated data transmission or reception. Since the UE cannot perform dedicated data reception when in the inactive state, when downlink data is to be transmitted to the UE, the RAN pages the UE to trigger the UE to enter the connected state. When the UE has uplink data to transmit, the UE first enters the connected state before transmitting the uplink data.

[0026] To enter the connected state from the inactive state, the UE performs an RRC recovery procedure 150, in which the UE context is retrieved from the UE's last serving cell and restored to the UE and the (new) serving cell. Compared to transitioning from the idle state to the connected state, the RRC recovery procedure speeds up the transition to the connected state by allowing the previous connection to be resumed without having to perform extensive NAS signaling.

[0027] Figure 2 An exemplary RRC recovery procedure 250 is outlined in FIG. 2. The UE is initially in an inactive state. At 210, the UE transmits an RRC recovery request to the gNB on which it is camping using a RACH procedure. The RRC recovery request includes an Inactive Radio Network Temporary Identity (I-RNTI) for the UE, which was assigned to the UE by the network when the UE entered the inactive state. The network uses the I-RNTI provided with the recovery request to identify the UE and the last serving cell so that the new serving cell can obtain the UE context from the last serving cell.

[0028] When a UE wishes to communicate with the network and does not have allocated UL resources, the UE uses a RACH procedure to contact the network. Therefore, the UE uses a RACH procedure to transmit a recovery request to the network. There are two types of RACH procedures, namely, contention-based RACH (CBRA) and contention-free RACH (CFRA). In CBRA, the UE randomly selects a preamble to identify the UE in the initial message with the network. In CFRA, when the UE enters a state where the UE does not have allocated UL resources, the preamble is assigned to the UE by the network. CFRA will be discussed in more detail in the context of an inactive UE performing a direct transmission using CFRA.

[0029] exist Figure 3A and Figure 3B , which may be used to transmit an RRC recovery request. Although the RACH procedures are described herein in the context of transmitting a recovery request, the RACH procedures are used by the UE any time the UE desires to achieve uplink synchronization with the gNB, enter a connected state from an idle or inactive state, or obtain resources for uplink transmission while in the connected state.

[0030] Figure 3A A 4-step contention-based RACH (CBRA) procedure is shown. At 320, the UE transmits Msg1 including a preamble identifying the UE using a predetermined PRACH opportunity. In CBRA, the preamble is randomly selected by the UE from a set of possible preambles. In another type of RACH procedure, when the UE enters an inactive state or an idle state, a contention-free RACH (CFRA), a preamble, and optionally also a dedicated PRACH resource are configured to the UE. Because in CBRA, another UE can select the same preamble via the same PRACH resource, CBRA includes a contention resolution step 350 as will be described below. In addition to the preamble, the UE also indicates a response window during which the UE expects a response from the gNB. If the UE does not receive a response within the window, the UE will retransmit the preamble and / or take other remedial measures.

[0031] At 330, the gNB transmits Msg2 containing a RACH response (RAR) including downlink control information (DCI) scrambled based on the preamble transmitted by the UE. The DCI includes information that enables the UE to decode the physical downlink shared channel (PDSCH), which conveys an identifier for the UE and an allocation of UL resources for use by the UE. At 340, the UE transmits Msg3 using the UL resources received in the RAR. In this example, Msg3 will include a recovery request. In other examples, the Msg3 may include other data.

[0032] At 350, the UE sets a contention timer when sending Msg3 and monitors the Physical Downlink Control Channel (PDCCH) for Msg4 sent by the gNB. Msg4 includes a Level 2 Medium Access Control Physical Data Unit (L2 MAC PDU) that includes a Contention Resolution MAC Control Element (CE) used by the UE to determine whether the RACH procedure was successful. When the UE does not receive Msg4 before the timer expires, it assumes that the RACH procedure was unsuccessful. At this point, the UE has successfully notified the gNB of its intent to enter the connected state (e.g., Figure 2 Step 210 is completed).

[0033] Figure 3B A two-step CBRA process 360 is shown. At 370, the UE transmits MsgA, which includes Figure 3A The information sent in Msg1 and Msg3 of the 4-step RACH procedure of the gNB. MsgA includes a randomly selected preamble transmitted on PRACH resources and an RRC recovery request transmitted using PUSCH resources. At 380, the gNB transmits MsgB, which may include a fallback RAR, which includes an uplink grant for the UE to retransmit MsgA when the gNB detects MsgA but cannot decode it. If the gNB successfully decodes MsgA, then MsgB includes a success RAR, which may include a new UL / DL grant for subsequent communication of data (not a retransmission of the RRC recovery request). At this point, the UE has successfully notified the gNB of its intention to enter the connected state (e.g., Figure 2 In CFRA, at 360, the pre-assigned preamble and dedicated PRACH resources (assigned by the gNB) may be used.

[0034] Return to Figure 2, at 220, after having received a resume request by the gNB, the gNB requests UE context information, which was stored by the last serving gNB as part of the RRC suspend procedure. At 230, the last serving gNB provides the UE context information to the new serving gNB. At 240, the gNB transmits an RRC resume message to the UE to indicate that the UE may enter the connected state. At 260, the UE indicates to the gNB that the UE has successfully entered the connected state. At 270, the gNB transmits a path switch request to update the radio bearers for the UE to the access and mobility management function (AMF), which is the gNB's interface with the CN. At 280, the AMF responds to the gNB, confirming that the path switch is complete. At 290, the gNB notifies the last serving gNB that the UE context may be deleted. After these communications have occurred, the UE may transmit data to and receive data from the gNB.

[0035] Reference Figure 4A , it can be seen that the recovery process introduces a significant delay between when the UE has data to transmit and when the UE is able to transmit the data. This document discloses systems, circuits, and techniques for enabling a UE to perform direct data transmission to a gNB using CFRA when in an inactive state without transitioning to a connected state, such as Figure 4B shown.

[0036] In CFRA, the network may identify the UE via dedicated physical random access channel (PRACH) resources (e.g., resources that may be used to transmit RACH messages or data) and / or dedicated preamble resources (e.g., preambles assigned to the UE for transmission using preamble resources). Dedicated PRACH resources and / or dedicated preamble resources are referred to herein as "dedicated PRACH / preamble resources," which are configured by the network to the UE. The dedicated PRACH / preamble configuration is configured to the UE via an RRC or physical downlink control channel (PDCCH) command and is valid within the serving cell. CFRA is triggered by the following events: uplink synchronization, downlink data arrival, handover, and beam failure recovery. This article proposes an extension of CFRA in which dedicated PRACH / preamble resources are used to identify inactive UEs so that the UEs can transmit uplink data. The UE uses dedicated PRACH / preamble resources to establish a CFRA procedure in which the UE performs direct uplink transmission when in an inactive state.

[0037] Figure 5A and Figure 5BA network is shown in which a UE roams within a radio access network (RAN) comprising five cells. The UE accesses the core network by means of one or more cells of the RAN. For the purpose of this specification, "cell" means a collection of infrastructure equipment (such as base stations, eNBs, gNBs, etc.) serving a given geographical area. When the UE is in a connected state or an inactive state, the UE selects and camps on at least one cell (e.g., a serving cell). When the UE exchanges messages or data with a base station or gNB, it should be understood that these terms are shorthand for any infrastructure equipment that constitutes a serving cell for the UE. The RAN includes a RAN notification area that includes cells 1 to 4. The UE can roam within the RAN notification area without notifying the RAN because cells 1 to 4 broadcast paging messages to any UE with a serving cell within the RAN notification area. The RAN also includes a CFRA configuration area that includes cells that support direct uplink transmissions by inactive UEs using CFRA.

[0038] The network (via serving cell 1) assigns dedicated PRACH / preamble resources to the UE as part of the RRC suspension procedure. While in the inactive state, the UE identifies uplink data to be transmitted to the network. If cell 1 is still the serving cell for the UE, the UE may perform CFRA using the dedicated PRACH / preamble resources received during the RRC suspension procedure to transmit uplink data to the network via cell 1.

[0039] However, if the UE has performed cell reselection and is now camping on cell 3 (which is within the CFRA configuration region), the question arises as to how the new serving cell allocates dedicated PRACH / preamble resources to the UE for direct uplink transmission. Figure 5A As shown, each cell in the CFRA configuration area broadcasts a message indicating that the cell supports direct uplink transmission by inactive UEs. In this example, the UE can assume that it can use the dedicated PRACH / preamble resources received during the RRC suspension process to transmit uplink data using CFRA to any cell that transmits the message.

[0040] For example, Figure 5BAs shown, the broadcast message includes which "supported" PRACH / preamble resources are configured for the cell. In this example, the UE can assume that it can use the dedicated PRACH / preamble resources received during the RRC suspension process to transmit uplink data (using CFRA) only to the cell that broadcasts the message that the supported PRACH / preamble resources match the dedicated PRACH / preamble resources. In another example not shown, the broadcast message includes which "supported" PRACH / preamble resources are configured for direct transmissions by inactive UEs to the cell. In this example, the UE can assume that it can use the dedicated PRACH / preamble resources received during the RRC suspension process to transmit uplink data (using CFRA) only to the cell that broadcasts the message that the supported PRACH / preamble resources match the dedicated PRACH / preamble resources.

[0041] As another example, the network configures dedicated preamble resources to the UE during the RRC suspension process, and the UE obtains dedicated PRACH / preamble resources from a broadcast message broadcast by each cell in which the UE is camping. The UE may use the dedicated preamble to perform direct uplink transmission (using CFRA) using any PRACH resources configured by the broadcast message of the given camped cell. Alternatively, the UE may use the dedicated preamble to perform direct uplink transmission (using CFRA) with any camped cell that broadcasts a message indicating that the cell supports direct uplink transmission using dedicated PRACH / preamble resources. Alternatively, the UE may use the dedicated preamble to perform direct uplink transmission (using CFRA) with any camped cell that broadcasts a message indicating that the cell supports direct uplink transmission.

[0042] Figure 6A message flow 610 outlining an example of a direct uplink transmission using CFRA is shown. At 620, the network (e.g., cell 1) configures a UE entering an inactive state with dedicated PRACH / preamble resources. While in the inactive state, the UE performs a direct uplink transmission using CFRA and dedicated PRACH / preamble resources. At 630, the UE transmits MsgA of a two-step RACH procedure to the cell using the dedicated PRACH / preamble resources. MsgA includes uplink data. In response, at 640, the cell transmits MsgB of a two-step RACH procedure including a CFRA resource validity indication value. When the CFRA resource validity indication value is 1, the dedicated PRACH / preamble resources remain valid for future direct uplink transmissions using CFRA. If the CFRA resource validity indication value is 0, the dedicated PRACH / preamble resources are invalid for future direct uplink transmissions using CFRA. In one example, the CFRA resource validity indication value is transmitted using an L2 control packet data unit (PDU) (e.g., a medium access control (MAC) control element (CE)). In another example, the cell provides a dedicated PRACH / preamble resource for the next direct uplink transmission using CFRA via an L2 control PDU (e.g., a MAC CE).

[0043] Figure 7 is an overview of the ways in which a UE can be configured to Figure 5A and Figure 5B Flowchart of an example of a mode of transmitting uplink data in different cells in a network of a network of RAN. Note that even though cell 2 is in the CFRA configuration area, cell 2 does not support direct uplink transmission using CFRA for the UE. The UE receives the configured dedicated PRACH / preamble resources from cell 1 during the RRC suspend procedure and enters an inactive state. While in the inactive state, the UE may perform direct uplink transmission using CFRA with both cell 1 (a serving cell configured with dedicated PRACH / preamble resources) and cell 3 (which is in the CFRA configuration area). The UE may perform direct uplink transmission using contention-based random access (CBRA) with cell 2 (which does not support direct uplink transmission using CFRA for the UE) and also with cell 4 (which is in the RAN notification area). In order to transmit uplink data to cell 5 outside the RAN notification area, the UE triggers an RRC recovery procedure to enter a connected state and transmit uplink data when connected. Alternatively, in some examples, the UE may perform direct uplink transmission with cell 5 (outside the RAN notification area) using CBRA.

[0044] Figure 8is a flow chart outlining an exemplary use of a timer for limiting the validity of dedicated PRACH / preamble resources. The UE receives dedicated PRACH / preamble resources and a time limit value during an RRC suspension procedure. At this point, the UE starts the timer. When the UE performs a direct uplink transmission using CFRA, the UE suspends the timer and restarts the time after the uplink transmission is completed. The dedicated PRACH / preamble resources are suspended or deleted by the UE upon expiration of the timer (e.g., when the timer value reaches the time limit) or upon entering a connected state.

[0045] Fig.9A A flow chart outlining a four-step CFRA process 900 is shown that can be used by a UE for direct uplink transmissions when inactive. At 910, the UE transmits a dedicated preamble in Msg1 and starts a RAR window. At 920, the network (e.g., a cell or base station) transmits Msg2 (RAR) within the RAR window including an uplink grant, which means that the CFRA process was successful. At 930, the UE transmits uplink data according to the uplink grant in Msg2 while still inactive. The network may provide a validity timer or a CFRA resource validity indication value in Msg2.

[0046] Fig. 9B A flow chart outlining a four-step process 940 that may be used by a UE for direct uplink transmissions while inactive is shown. At 910, the UE transmits a dedicated preamble to the network (e.g., a cell or base station). At 950, the network transmits a dedicated physical downlink control channel (PDCCH) schedule scrambled using an inactive radio network temporary identity (I-RNTI) assigned to the UE when it entered the inactive state. The dedicated PDCCH schedules PUSCH transmission of a Tracking Area Code (TAC) MAC CE. At 960, the UE transmits uplink data with the aid of a TAC MAC CE according to the dedicated PDCCH schedule while still inactive.

[0047] Fig. 10AA flow chart outlining a two-step CFRA process 1000 is shown that can be used by a UE for direct uplink transmissions while inactive. At 1010, the UE transmits a dedicated preamble and uplink data in a MsgA-PUSCH resource and starts an MsgB window. At 1020, the network (e.g., a cell or base station) transmits an MsgB that includes an uplink grant within the MsgB window, meaning that the network cannot decode the uplink transmission. At 1030, the UE transmits uplink data in accordance with the uplink grant in the MsgB while still inactive. If the UE receives a new uplink grant instead of the MsgB, the UE is notified that the uplink transmission was successful and that subsequent data can be transmitted with the aid of the new uplink grant. The network may provide a validity timer or a CFRA resource validity indication value in the MsgB.

[0048] Fig. 10B A flow chart outlining a two-step process 1040 is shown that can be used by a UE for direct uplink transmission while inactive. At 1010, the UE transmits a dedicated preamble and uplink data in a PUSCH resource. At 1050, when the UE enters an inactive state, the network transmits a dedicated PDCCH schedule scrambled using the I-RNTI assigned to the UE. The dedicated PDCCH schedules the PUSCH transmission of a TAC MAC CE by the UE transmitting uplink data. At 1060, the UE transmits uplink data with the aid of a TAC MAC CE according to the dedicated PDCCH schedule while still inactive.

[0049] Below are several flow charts outlining example methods. In this specification and the appended claims, the use of the term "determine" in describing method steps or functions with reference to some entity (e.g., parameter, variable, etc.) is to be interpreted broadly. For example, "determine" is interpreted to cover communications such as receiving and parsing an encoded entity or value of an entity. "Determine" should be interpreted to cover accessing and reading a memory (e.g., a lookup table, register, device memory, remote memory, etc.) storing an entity or value for an entity. "Determine" should be interpreted to cover calculating or deriving an entity or value of an entity based on other quantities or entities. "Determine" should be interpreted to cover any way of inferring or identifying an entity or value of an entity.

[0050] As used herein, the term "identify" when used with reference to an entity or a value of an entity is to be broadly interpreted to encompass any manner of determining an entity or a value of an entity. For example, the term "identify" is to be interpreted to encompass, for example, receiving and parsing communications encoding an entity or a value of an entity. The term "identify" should be interpreted to encompass accessing and reading a memory storing an entity or a value for an entity (e.g., a device queue, a lookup table, a register, a device memory, a remote memory, etc.).

[0051] As used herein, the term "select" when used with reference to an entity or value of an entity is to be interpreted broadly to encompass any manner of determining an entity or value of an entity from a plurality or a range of possible choices. For example, the term "select" is interpreted to encompass accessing and reading a memory (e.g., a lookup table, register, device memory, remote memory, etc.) storing an entity or value for an entity and returning an entity or entity value from those stored. The term "select" is interpreted to be applying one or more constraints or rules to a set of input parameters to determine an appropriate entity or entity value. The term "select" is interpreted to broadly encompass any manner of selecting an entity based on one or more parameters or conditions.

[0052] As used herein, the term "derive" is to be interpreted broadly when used with reference to an entity or a value of an entity. "Derivation" should be interpreted to encompass accessing and reading a memory (e.g., a lookup table, a register, a device memory, a remote memory, etc.) that stores some initial or underlying values, and performing processing and / or logical / mathematical operations on one or more values ​​to generate a derived entity or a value for an entity. "Derivation" should be interpreted to encompass calculating or measuring an entity or a value of an entity based on other quantities or entities. "Derivation" should be interpreted to encompass any way of inferring or identifying an entity or a value of an entity.

[0053] Fig.11 A flow chart outlining a method 1100 to be performed by a BS is shown. The method optionally includes, at 1110, transmitting to a user equipment (UE) device a configured dedicated PRACH / preamble resource assigned to the UE by the network during an RRC suspension procedure. At 1120, the method includes receiving uplink data transmitted by the user equipment (UE) device when the UE is in a radio resource control (RRC) inactive state. The UE uses a contention-free random access (CFRA) procedure to transmit the uplink data using the dedicated PRACH / preamble resource. The functions performed at 1110 are optional because the BS receiving the uplink data may be different from the BS that transmitted the configuration of the dedicated PRACH / preamble resource.

[0054] Fig.12 An exemplary architecture of a system 1200 of a communication network according to various aspects is shown. The following description is provided for an exemplary system 1200 operating in conjunction with LTE system standards and 5G or NR system standards provided by 3GPP technical specifications. However, the exemplary aspects are not limited in this regard, and the described aspects may be applied to other networks that benefit from the principles described herein, such as future 3GPP systems (e.g., sixth generation (6G)) systems, IEEE 702.16 protocols (e.g., WLAN, WiMAX, etc.), and the like.

[0055] like Fig.12 As shown, system 1200 includes UE 1201a and UE 1201b (collectively referred to as "UE 1201"). In this example, multiple UEs 1201 are shown as smart phones (e.g., handheld touch screen mobile computing devices that can connect to one or more cellular networks), but may also include any mobile or non-mobile computing devices, such as consumer electronic devices, mobile phones, smart phones, feature phones, tablet computers, wearable computer devices, personal digital assistants (PDAs), pagers, wireless handheld devices, desktop computers, laptop computers, in-vehicle infotainment (IVI), in-vehicle entertainment (ICE) devices, instrument panels (ICs), head-up display (HUD) devices, on-board diagnostic (OBD) devices, dashtop mobile equipment (DME), mobile data terminals (MDTs), electronic engine management systems (EEMS), electronic / engine electronic control units (ECUs), electronic / engine electronic control modules (ECMs), embedded systems, microcontrollers, control modules, engine management systems (EMS), networked or "smart" appliances, MTC devices, M2M, IoT devices, etc.

[0056] In some aspects, any of the UEs 1201 may be an IoT UE, which may include a network access layer designed for low-power IoT applications that utilize short-term UE connections. The IoT UE may utilize technologies such as M2M or MTC to exchange data with an MTC server or device via PLMN, ProSe or D2D communications, sensor networks, or IoT networks. The M2M or MTC data exchange may be a machine-initiated data exchange. The IoT network describes interconnected IoT UEs, which may include uniquely identifiable embedded computing devices (within the Internet infrastructure) with short-lived connections. The IoT UE may execute background applications (e.g., keep-alive messages, status updates, etc.) to facilitate connectivity to the IoT network.

[0057] UE 1201 may be configured to connect, e.g., be communicatively coupled, to RAN 1210. In aspects, RAN 1210 may be an NG RAN or 5G RAN, E-UTRAN, or a legacy RAN, such as UTRAN or GERAN. As used herein, the term "NG RAN" or the like may refer to RAN 1210 operating in NR or 5G system 1200, while the term "E-UTRAN" or the like may refer to RAN 1210 operating in LTE or 4G system 1200. UE 1201 utilizes connections (or channels) 1203 and 1204, respectively, each connection comprising a physical communication interface or layer (discussed in further detail below).

[0058] In this example, connections 1203 and 1204 are shown as air interfaces to achieve communication coupling, and may be consistent with a cellular communication protocol, such as a GSM protocol, a CDMA network protocol, a PTT protocol, a POC protocol, a UMTS protocol, a 3GPP LTE protocol, a 5G protocol, a NR protocol, and / or any other communication protocol discussed herein. In an aspect, the UE 1201 may directly exchange communication data via a ProSe interface 1205. The ProSe interface 1205 may alternatively be referred to as a SL interface 1205, and may include one or more logical channels, including but not limited to a PSCCH, a PSSCH, a PSDCH, and a PSBCH.

[0059] UE 1201b is shown as being configured to access AP 1206 (also referred to as "WLAN node 1206," "WLAN 1206," "WLAN terminal 1206," "WT 1206," etc.) via connection 1207. Connection 1207 may include a local wireless connection, such as a connection consistent with any IEEE 702.11 protocol, where AP 1206 would include Wireless Fidelity (Wi-Fi ® ) router. In this example, AP 1206 is shown connected to the Internet without being connected to the core network of the wireless system (described in further detail below). In various aspects, UE 1201b, RAN 1210, and AP 1206 can be configured to utilize LWA operation and / or LWIP operation. LWA operation may involve UE 1201b in RRC_CONNECTED state configured by RAN nodes 1211a-b to utilize radio resources of LTE and WLAN. LWIP operation may involve UE 1201b using WLAN radio resources (e.g., connection 1207) via an IPsec protocol tunnel to authenticate and encrypt packets (e.g., IP packets) sent through connection 1207. IPsec tunneling may include encapsulating the entire original IP packet and adding a new packet header, thereby protecting the original header of the IP packet.

[0060] The RAN 1210 includes one or more AN nodes or RAN nodes 1211a and 1211b (collectively referred to as "RAN nodes 1211") that enable connections 1203 and 1204. As used herein, the terms "access node", "access point", etc. may describe equipment that provides radio baseband functions for data and / or voice connections between a network and one or more users. These access nodes may be referred to as BS, gNB, RAN node, eNB, NodeB, RSU, TRxP or TRP, etc., and may include ground stations (e.g., terrestrial access points) or satellite stations that provide coverage within a geographic area (e.g., a cell). As used herein, the terms "NG RAN node" and the like may refer to a RAN node 1211 (e.g., a gNB) operating in an NR or 5G system 1200, while the terms "E-UTRAN node" and the like may refer to a RAN node 1211 (e.g., an eNB) operating in an LTE or 4G system 1200. According to various aspects, the RAN node 1211 may be implemented as one or more of a dedicated physical device such as a macrocell base station and / or a low power (LP) base station for providing a femtocell, picocell or other similar cell with a smaller coverage area, smaller user capacity or higher bandwidth than a macrocell.

[0061] According to various aspects, UE 1201 and RAN node 1211 communicate data (e.g., transmit data and receive data) through a licensed medium (also referred to as a "licensed spectrum" and / or a "licensed band") and an unlicensed shared medium (also referred to as an "unlicensed spectrum" and / or an "unlicensed band"). The licensed spectrum may include channels operating in a frequency range of approximately 400 MHz to approximately 3.8 GHz, and the unlicensed spectrum may include a 5 GHz band.

[0062] To operate in the unlicensed spectrum, the UE 1201 and the RAN node 1211 may operate using LAA, eLAA, and / or feLAA mechanisms. In these implementations, the UE 1201 and the RAN node 1211 may perform one or more known medium sensing operations and / or carrier sensing operations to determine whether one or more channels in the unlicensed spectrum are unavailable or otherwise occupied before transmitting in the unlicensed spectrum. The medium / carrier sensing operations may be performed according to a listen-before-talk (LBT) protocol.

[0063] LBT is a mechanism by which equipment (e.g., UE 1201, RAN node 1211, etc.) senses the medium (e.g., a channel or carrier frequency) and transmits when the medium is sensed to be idle (or when a particular channel in the medium is sensed to be unoccupied). The medium sensing operation may include a CCA that utilizes at least an ED to determine whether other signals are present on the channel in order to determine whether the channel is occupied or idle. The LBT mechanism allows cellular / LAA networks to coexist with existing systems in unlicensed spectrum and with other LAA networks. ED may include sensing RF energy on an expected transmission band over a period of time and comparing the sensed RF energy to a predefined or configured threshold.

[0064] Typically, existing systems in the 5 GHz band are WLANs based on IEEE 702.11 technology. WLANs use a contention-based channel access mechanism called CSMA / CA. Here, when a WLAN node (e.g., a mobile station (MS) such as UE 1201, AP 1206, etc.) intends to transmit, the WLAN node may first perform CCA before transmission. In addition, in the case where more than one WLAN node senses the channel as idle and transmits at the same time, a backoff mechanism is used to avoid conflicts. The backoff mechanism may be a counter randomly introduced within the CWS that increases exponentially when a conflict occurs and is reset to a minimum value when the transmission is successful. The LBT mechanism designed for LAA is somewhat similar to CSMA / CA for WLAN. In some specific implementations, the LBT process for a DL or UL transmission burst (including PDSCH or PUSCH transmission) may have a LAA contention window of variable length between X and Y ECCA slots, where X and Y are the minimum and maximum values ​​of the CWS for LAA. In one example, the minimum CWS for LAA transmissions may be 8 microseconds (µs); however, the size of the CWS and MCOT (eg, transmission burst) may be based on government regulatory requirements.

[0065] The LAA mechanism is built on the CA technology of the LTE-Advanced system. In CA, each aggregated carrier is called a CC. A CC can have a bandwidth of 1.4, 3, 5, 10, 15, or 20 MHz, and up to five CCs can be aggregated, so the maximum aggregated bandwidth is 100 MHz. In an FDD system, the number of aggregated carriers can be different for DL ​​and UL, where the number of UL CCs is equal to or lower than the number of DL component carriers. In some cases, each CC may have a different bandwidth from other CCs. In a TDD system, the number of CCs and the bandwidth of each CC are typically the same for DL ​​and UL.

[0066] CA also includes individual serving cells to provide individual CCs. The coverage of the serving cells may be different, for example, because CCs on different frequency bands will experience different path losses. The primary serving cell or PCell may provide the PCC for both UL and DL, and may handle activities related to RRC and NAS. Other serving cells are called SCells, and each SCell may provide individual SCCs for both UL and DL. SCCs may be added and removed as needed, and changing PCCs may require UE 1201 to undergo a handover. In LAA, eLAA, and feLAA, some or all of the SCells may operate in an unlicensed spectrum (referred to as "LAA SCells"), and the LAA SCells are assisted by the PCells operating in the licensed spectrum. When a UE is configured with more than one LAA SCell, the UE may receive UL grants on the configured LAA SCells, indicating different PUSCH start positions within the same subframe.

[0067] The PDSCH carries user data and higher layer signaling to the UE 1201. The PDCCH carries, among other information, information about the transport format and resource allocation related to the PDSCH channel. It may also inform the UE 1201 about the transport format, resource allocation, and HARQ information related to the uplink shared channel. Typically, downlink scheduling (allocation of control and shared channel resource blocks to UE 1201b within a cell) may be performed at any of the RAN nodes 1211 based on channel quality information fed back from any of the UEs 1201. Downlink resource allocation information may be sent on the PDCCH for (e.g., allocated to) each of the UEs 1201.

[0068] RAN 1210 is shown as being communicatively coupled to a core network—in this aspect, to a core network (CN) 1220. CN 1220 may include a plurality of network elements 1222 configured to provide various data and telecommunication services to customers / subscribers (e.g., users of UE 1201) connected to CN 1220 via RAN 1210. Components of CN 1220 may be implemented in one physical node or separate physical nodes, including components for reading and executing instructions from a machine-readable or computer-readable medium (e.g., a non-transitory machine-readable storage medium). In some aspects, NFV may be used to virtualize any or all of the above-described network node functions via executable instructions stored in one or more computer-readable storage media (described in further detail below). A logical instance of CN 1220 may be referred to as a network slice, and a logical instance of a portion of CN 1220 may be referred to as a network sub-slice. NFV architecture and infrastructure may be used to virtualize one or more network functions onto physical resources comprising a combination of industry-standard server hardware, storage hardware, or switches (alternatively performed by proprietary hardware). In other words, the NFV system may be used to perform a virtual or reconfigurable implementation of one or more EPC components / functions.

[0069] Fig.13 An example of infrastructure equipment 1300 according to various aspects is shown. Infrastructure equipment 1300 (or "system 1300") can be implemented as a base station, a radio head, a RAN node (such as the RAN node 1211 and / or AP 1206 shown and described previously), an application server 1230, and / or any other element / device discussed herein. In other examples, system 1300 can be implemented in or by a UE.

[0070] System 1300 includes: application circuit 1305, baseband circuit 1310, one or more radio front end modules (RFEM) 1315, memory circuit 1320, power management integrated circuit (PMIC) 1325, power tee circuit 1330, network controller circuit 1335, network interface connector 1340, satellite positioning circuit 1345 and user interface 1350. In some aspects, device 1300 may include additional elements such as, for example, memory / storage, display, camera, sensor or input / output (I / O) interface. In other aspects, the following components may be included in more than one device. For example, the circuit may be separately included in more than one device for CRAN, vBBU or other similar implementations.

[0071] The application circuit 1305 may include circuits such as, but not limited to, one or more processors (or processor cores), cache memory, and one or more of the following: a low dropout regulator (LDO), an interrupt controller, a serial interface such as SPI, I2C or a general programmable serial interface module, a real-time clock (RTC), a timer-counter (including an interval timer and a watchdog timer), a general input / output (I / O or IO), a memory card controller such as a secure digital (SD) multimedia card (MMC) or similar products, a universal serial bus (USB) interface, a mobile industry processor interface (MIPI) interface, and a joint test access group (JTAG) test access port. The processor (or core) of the application circuit 1305 may be coupled to or may include a memory / storage element, and may be configured to execute instructions stored in the memory / storage device to enable various applications or operating systems to run on the system 1300. In some implementations, the memory / storage element can be an on-chip memory circuit that can include any suitable volatile and / or non-volatile memory, such as DRAM, SRAM, EPROM, EEPROM, flash memory, solid-state memory, and / or any other type of memory device technology, such as those discussed herein.

[0072] The processor of application circuit 1305 may include, for example, one or more processor cores (CPUs), one or more application processors, one or more graphics processing units (GPUs), one or more reduced instruction set computing (RISC) processors, one or more Acorn RISC Machine (ARM) processors, one or more complex instruction set computing (CISC) processors, one or more digital signal processors (DSPs), one or more FPGAs, one or more PLDs, one or more ASICs, one or more microprocessors or controllers, or any suitable combination thereof. In some aspects, application circuit 1305 may include or may be a dedicated processor / controller for operating in accordance with various aspects of the present disclosure. As an example, the processor of application circuit 1305 may include one or more Apple ® Processor, Intel ® Processor: Advanced Micro Devices (AMD) Ryzen ® Processor, Accelerated Processing Unit (APU) or Epyc ® Processors; ARM-based processors licensed from ARM Holdings, Ltd., such as the ARM Cortex-A series processors and ThunderX2 provided by Cavium(TM), Inc. ®; MIPS-based designs from MIPS Technologies, Inc., such as the MIPS Warrior P-class processor; etc. In some aspects, system 1300 may not utilize application circuit 1305, and may instead include a dedicated processor / controller for processing IP data received, for example, from an EPC or 5GC.

[0073] The user interface circuit 1350 may include one or more user interfaces designed to enable a user to interact with the system 1300 or a peripheral component interface designed to enable a peripheral component to interact with the system 1300. The user interface may include, but is not limited to, one or more physical or virtual buttons (e.g., a reset button), one or more indicators (e.g., a light emitting diode (LED)), a physical keyboard or keypad, a mouse, a touch pad, a touch screen, a speaker or other audio transmitting device, a microphone, a printer, a scanner, a headset, a display screen or display device, etc. The peripheral component interface may include, but is not limited to, a non-volatile memory port, a universal serial bus (USB) port, an audio jack, a power interface, etc.

[0074] Fig.13 The components shown can communicate with each other using interface circuits that can include any number of bus and / or interconnect (IX) technologies, such as industry standard architecture (ISA), extended ISA (EISA), peripheral component interconnect (PCI), peripheral component interconnect extended (PCIx), PCI express (PCIe), or any number of other technologies. The bus / IX can be a proprietary bus, for example, used in a SoC-based system. Other bus / IX systems can be included, such as an I2C interface, an SPI interface, a point-to-point interface, and a power bus, etc.

[0075] Fig.14 An example of a platform 1400 (or "device 1400") according to various aspects is shown. In aspects, the computer platform 1400 can be suitable for use as a UE 1201, an application server 1230, and / or any other element / device discussed herein. The platform 1400 may include any combination of the components shown in the example. The components of the platform 1400 may be implemented as integrated circuits (ICs), portions of ICs, discrete electronic devices, or other modules, logic, hardware, software, firmware, or combinations thereof adapted in the computer platform 1400, or as components otherwise incorporated within a chassis of a larger system. Fig.14 The block diagram is intended to show a high-level view of the components of computer platform 1400. However, some of the components shown may be omitted, additional components may be present, and different arrangements of the components shown may occur in other implementations.

[0076] The application circuit 1405 includes circuits such as, but not limited to, one or more processors (or processor cores), cache memory, and one or more of an LDO, an interrupt controller, a serial interface (such as SPI), I2C or a general programmable serial interface module, an RTC, a timer-counter (including an interval timer and a watchdog timer), a general I / O, a memory card controller (such as an SD MMC or similar controller), a USB interface, a MIPI interface, and a JTAG test access port. The processor (or core) of the application circuit 1405 may be coupled to or may include a memory / storage element and may be configured to execute instructions stored in the memory / storage device to enable various applications or operating systems to run on the system 1400. In some specific implementations, the memory / storage element may be an on-chip memory circuit that may include any suitable volatile and / or non-volatile memory, such as DRAM, SRAM, EPROM, EEPROM, flash memory, solid-state memory, and / or any other type of memory device technology, such as those discussed herein.

[0077] For example, the processor of application circuit 1405 may include a general purpose or special purpose processor, such as a processor available from Apple ® Inc., Cupertino, CA's A-series processor (e.g., A13 Bionic) or any other such processor. The processor of the application circuit 1405 may also be one or more of the following: Advanced Micro Devices (AMD) Ryzen ® Processor or Accelerated Processing Unit (APU); from Intel ® Inc.'s core processor, from Qualcomm ® Snapdragon by Technologies, Inc. ™ Processors, Texas Instruments, Inc. ® Open Multimedia ApplicationsPlatform (OMAP) ™processors; MIPS-based designs from MIPS Technologies, Inc., such as the MIPS Warrior M-class, Warrior I-class, and Warrior P-class processors; ARM-based designs licensed from ARM Holdings, Ltd., such as the ARM Cortex-A, Cortex-R, and Cortex-M series processors; etc. In some implementations, the application circuit 1405 can be part of a system on a chip (SoC), in which the application circuit 1405 and other components are formed as a single integrated circuit or a single package.

[0078] Baseband circuit 1410 may be implemented, for example, as a solder-in substrate including one or more integrated circuits, a single packaged integrated circuit soldered to a main circuit board, or a multi-chip module containing two or more integrated circuits.

[0079] The platform 1400 may further include an interface circuit (not shown) for connecting external devices to the platform 1400. External devices connected to the platform 1400 via the interface circuit include a sensor circuit 1421 and an electromechanical component (EMC) 1422, and a removable memory device coupled to a removable memory circuit 1423.

[0080] The battery 1430 can power the platform 1400, but in some examples, the platform 1400 can be mounted in a fixed location and can have a power source coupled to a power grid. The battery 1430 can be a lithium-ion battery, a metal-air battery such as a zinc-air battery, an aluminum-air battery, a lithium-air battery, etc. In some implementations, such as in V2X applications, the battery 1430 can be a typical lead-acid car battery.

[0081] Although the method is shown above and described as a series of actions or events, it should be understood that the order of such actions or events shown should not be interpreted as having a limiting meaning. For example, some actions can occur simultaneously with other actions or events other than those shown and / or described herein in different orders. In addition, all the actions shown may not be required to implement one or more aspects or embodiments disclosed herein. In addition, one or more actions in the actions shown herein may be performed in one or more separate actions and / or stages. In some embodiments, the method shown above can be implemented in a computer-readable medium using instructions stored in a memory. Many other embodiments and variations are possible within the scope of the present disclosure protected by the claims. Example

[0082] Embodiment 1 is a device comprising one or more processors configured to receive uplink data from a user equipment (UE) when the UE is in a radio resource control (RRC) inactive state, wherein the UE uses a contention-free random access (CFRA) procedure to transmit the uplink data using dedicated physical random access channel (PRACH) resources or dedicated preamble resources (dedicated PRACH / preamble resources) assigned to the UE by a network.

[0083] Embodiment 2 includes the subject matter described in embodiment 1, including or omitting the optional subject matter, wherein the one or more processors are configured to transmit the configuration of dedicated PRACH / preamble resources to the UE during the RRC suspension procedure.

[0084] Embodiment 3 includes the subject matter described in embodiment 2, including or omitting optional subject matter, wherein the one or more processors are configured to receive Msg1 of a random access control channel (RACH) process from a UE, the Msg1 including a preamble indicated by a dedicated PRACH / preamble resource; allocate a physical uplink shared channel (PUSCH) resource to the UE in Msg2 of the random access control channel (RACH) process; and receive uplink data from the UE on the PUSCH resource.

[0085] Embodiment 4 includes the subject matter described in embodiment 2, including or omitting optional subject matter, wherein the one or more processors are configured to transmit an indication of PUSCH resources assigned to the UE by the network during an RRC suspension procedure; receive a preamble indicated in a dedicated PRACH / preamble resource on the PRACH resources indicated in the dedicated PRACH / preamble resource; and receive uplink data from the UE on the indicated PUSCH resources in a MsgA of a random access control channel (RACH) procedure.

[0086] Embodiment 5 includes the subject matter described in embodiment 1, including or omitting optional subject matter, wherein the one or more processors are configured to determine that uplink data transmitted by the UE in MsgA of the RACH process cannot be decoded; in response, assign PUSCH resources to the UE; transmit an indication of the PUSCH resources in MsgB of the RACH process; and receive uplink data on the PUSCH resources.

[0087] Embodiment 6 includes the subject matter described in Embodiment 1, including or omitting the optional subject matter, wherein the one or more processors are configured to broadcast a message indicating that the cell on which the UE is camping supports direct uplink transmissions from inactive UEs.

[0088] Embodiment 7 includes the subject matter described in embodiment 1, including or omitting optional subject matter, wherein the one or more processors are configured to broadcast a message indicating that the cell on which the UE is residing supports direct uplink transmissions from inactive UEs and identifies supported PRACH / preamble resources.

[0089] Embodiment 8 includes the subject matter described in embodiment 1, including or omitting optional subject matter, wherein the one or more processors are configured to broadcast a message indicating that the cell on which the UE is residing supports direct uplink transmissions from inactive UEs and identifying supported PRACH / preamble resources for direct uplink transmissions from inactive UEs.

[0090] Embodiment 9 includes the subject matter of embodiment 1, including or omitting the optional subject matter, wherein the one or more processors are configured to broadcast a message indicating a dedicated PRACH / preamble resource for a cell on which the UE is camping.

[0091] Embodiment 10 includes the subject matter described in embodiment 1, including or omitting optional subject matter, wherein the one or more processors are configured to transmit a validity indication flag in Msg3 of the RACH process, wherein the validity indication flag indicates whether the dedicated PRACH / preamble code resource is valid or invalid.

[0092] Embodiment 11 includes the subject matter described in embodiment 1, including or omitting optional subject matter, wherein the one or more processors are configured to transmit a validity indication flag in MsgB of the RACH process, wherein the validity indication flag indicates whether the dedicated PRACH / preamble code resource is valid or invalid.

[0093] Embodiment 12 includes the subject matter of Embodiments 10 to 11, including or omitting the optional subject matter, wherein the one or more processors are configured to transmit a validity indicator in an L2 control packet data unit (PDU).

[0094] Embodiment 13 includes the subject matter described in Embodiment 1, including or omitting optional subject matter, wherein the one or more processors are configured to transmit subsequent dedicated PRACH / preamble resources to the UE in the L2 control PDU, wherein the UE uses the CFRA process to use the subsequent PRACH / preamble resources to transmit subsequent uplink data.

[0095] Embodiment 14 is a method, comprising: when a user equipment (UE) is in a radio resource control (RRC) inactive state, receiving uplink data from the UE, wherein the UE uses a contention-free random access (CFRA) procedure to transmit the uplink data using dedicated physical random access channel (PRACH) resources or dedicated preamble resources (dedicated PRACH / preamble resources) assigned to the UE by a network.

[0096] Embodiment 15 includes the subject matter of embodiment 14, including or omitting the optional subject matter, the method further comprising: transmitting the configuration of the dedicated PRACH / preamble resources to a user equipment (UE) device during an RRC suspension procedure.

[0097] Embodiment 16 includes the subject matter described in embodiment 15, including or omitting optional subjects, and the method further includes: receiving Msg1 of a random access control channel (RACH) process from the UE, the Msg1 including a preamble indicated by a dedicated PRACH / preamble resource; allocating a physical uplink shared channel (PUSCH) resource to the UE in Msg2 of the random access control channel (RACH) process; and receiving uplink data from the UE on the PUSCH resource.

[0098] Embodiment 17 includes the subject matter described in embodiment 15, including or omitting optional subject matter, the method further comprising: transmitting an indication of PUSCH resources assigned to the UE by the network during an RRC suspension procedure; receiving a preamble indicated in a dedicated PRACH / preamble resource on the PRACH resources indicated in the dedicated PRACH / preamble resource; and receiving uplink data from the UE on the indicated PUSCH resources in MsgA of a random access control channel (RACH) procedure.

[0099] Embodiment 18 includes the subject matter described in embodiment 14, including or omitting optional subject matter, the method further comprising: determining that uplink data transmitted by the UE in MsgA of the RACH process cannot be decoded; in response, assigning PUSCH resources to the UE; transmitting an indication of the PUSCH resources in MsgB of the RACH process; and receiving uplink data on the PUSCH resources.

[0100] Embodiment 19 includes the subject matter described in embodiment 14, including or omitting the optional subject matter, and the method further includes: broadcasting a message indicating that the cell on which the UE is camping supports direct uplink transmission from the inactive UE.

[0101] Embodiment 20 includes the subject matter described in embodiment 14, including or omitting optional subject matter, the method further comprising: broadcasting a message indicating that the cell on which the UE is residing supports direct uplink transmission from inactive UEs and identifying supported PRACH / preamble resources.

[0102] Embodiment 21 includes the subject matter described in embodiment 14, including or omitting optional subject matter, the method further comprising: broadcasting a message indicating that the cell on which the UE is residing supports direct uplink transmission from inactive UEs, and identifying supported PRACH / preamble resources for direct uplink transmission from inactive UEs.

[0103] Embodiment 22 includes the subject matter of embodiment 14, including or omitting the optional subject matter, the method further comprising: broadcasting a message indicating a dedicated PRACH / preamble resource for the cell on which the UE is camping.

[0104] Embodiment 23 includes the subject matter described in Embodiment 14, including or omitting optional subjects, and the method further includes: transmitting a validity indication identifier in Msg3 of the RACH process, wherein the validity indication identifier indicates whether the dedicated PRACH / preamble code resource is valid or invalid.

[0105] Embodiment 24 includes the subject matter described in Embodiment 14, including or omitting optional subject matter, and the method further includes: transmitting a validity indication identifier in MsgB of the RACH process, wherein the validity indication identifier indicates whether the dedicated PRACH / preamble code resource is valid or invalid.

[0106] Embodiment 25 includes the subject matter described in Embodiments 23 to 24, including or omitting the optional subject matter, and the method further includes: transmitting a validity indication identifier in an L2 control packet data unit (PDU).

[0107] Embodiment 26 includes the subject matter described in Embodiment 14, including or omitting optional subject matter, the method further comprising: transmitting subsequent dedicated PRACH / preamble resources to the UE in an L2 control PDU, wherein the UE uses a CFRA process to use subsequent PRACH / preamble resources to transmit subsequent uplink data.

[0108] The term "coupled" is used throughout the specification. The term can cover connections, communications, or signal paths that enable a functional relationship consistent with the description of the present disclosure. For example, if device A generates a signal to control device B to perform an action, then in the first example, device A is coupled to device B, or in the second example, if the intermediate component C does not substantially change the functional relationship between device A and device B so that device B is controlled by device A via the control signal generated by the device, then device A is coupled to device B through the intermediate component C.

[0109] It is understood that the use of personally identifiable information should be subject to privacy policies and practices that are generally recognized to meet or exceed industry or government requirements for maintaining user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of unintentional or unauthorized access or use, and the nature of the authorized use should be clearly stated to users.

Claims

1. A device for a base station, comprising: Memory; and one or more processors coupled to the memory, the one or more processors being configured to, when executing instructions stored in the memory, cause the base station to: broadcasting a message indicating that a first cell associated with the base station supports direct uplink transmission from a user equipment UE in a radio resource control RRC inactive state; receiving, from the UE, a physical random access channel (PRACH) preamble on a preamble resource during a contention-free random access (CFRA) procedure with a first cell, wherein the PRACH preamble or preamble resource is assigned to the UE by a network through signaling from a second cell different from the first cell to the UE for performing direct uplink transmission without entering an RRC connected state; and During the CFRA procedure, uplink data is received from the UE while the UE is in an RRC inactive state.

2. The apparatus of claim 1 , wherein the one or more processors are configured to cause the base station to: Determining that uplink data transmitted by the UE in MsgA of the RACH procedure cannot be decoded; In response, assigning PUSCH resources to the UE; Transmitting an indication of the PUSCH resource in MsgB of the RACH procedure; as well as The uplink data is received on the PUSCH resource.

3. The apparatus of claim 1 , wherein the one or more processors are configured to cause the base station to: A validity indication flag is transmitted in Msg2 of the RACH process, wherein the validity indication flag indicates whether the PRACH preamble or preamble resource is valid or invalid.

4. The apparatus of claim 1 , wherein the one or more processors are configured to cause the base station to: A validity indication flag is transmitted in MsgB of the RACH process, wherein the validity indication flag indicates whether the PRACH preamble or preamble resource is valid or invalid.

5. The apparatus according to any one of claims 3 to 4, wherein the one or more processors are configured to cause the base station to: The validity indicator is transmitted in an L2 control packet data unit (PDU), wherein the validity indicator indicates whether the PRACH preamble or preamble resource is valid or invalid.

6. The apparatus of claim 1, wherein the one or more processors are configured to cause the base station to: Broadcasting a message indicating that a first cell supports one or more supported PRACH preambles or supported preamble resources for direct uplink transmission from a UE in an RRC inactive state, wherein a PRACH preamble received from the UE matches one of the supported PRACH preambles or a preamble resource from which the PRACH preamble is received from the UE matches one of the supported preamble resources.

7. A method for wireless communication, comprising: broadcasting a message indicating that the first cell supports direct uplink transmission from a user equipment UE in a radio resource control RRC inactive state; receiving, from the UE, a physical random access channel (PRACH) preamble on a preamble resource during a contention-free random access (CFRA) procedure with a first cell, wherein the PRACH preamble or preamble resource is assigned to the UE by a network through signaling from a second cell different from the first cell to the UE for performing direct uplink transmission without entering an RRC connected state; and During the CFRA procedure, uplink data is received from the UE while the UE is in an RRC inactive state.

8. The method according to claim 7, further comprising: Broadcasting a message indicating that a first cell supports one or more supported PRACH preambles or supported preamble resources for direct uplink transmission from a UE in an RRC inactive state, wherein a PRACH preamble received from the UE matches one of the supported PRACH preambles or a preamble resource from which the PRACH preamble is received from the UE matches one of the supported preamble resources.

9. The method according to claim 7, further comprising: Determining that uplink data transmitted by the UE in MsgA of the RACH procedure cannot be decoded; In response, assigning PUSCH resources to the UE; Transmitting an indication of the PUSCH resource in MsgB of the RACH procedure; as well as The uplink data is received on the PUSCH resource.

10. The method according to claim 7, further comprising: A validity indication flag is transmitted in Msg2 of the RACH process, wherein the validity indication flag indicates whether the PRACH preamble or preamble resource is valid or invalid.

11. The method according to claim 7, further comprising: A validity indication flag is transmitted in MsgB of the RACH process, wherein the validity indication flag indicates whether the PRACH preamble or preamble resource is valid or invalid.

12. The method according to any one of claims 10 to 11, further comprising: The validity indication flag is transmitted in an L2 control packet data unit (PDU).

13. The method according to claim 7, further comprising: A subsequent PRACH preamble or preamble resource is transmitted to the UE in an L2 control PDU, wherein the UE uses the CFRA procedure to transmit subsequent uplink data using the subsequent PRACH preamble or preamble resource.

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