JP-7855758-B2 - Method and apparatus for base station for subsequent transmission in an inactive state in wireless communication.

Inventors

• シュ ファンリ
• ヤオ チュンハイ
• チャン ダウェイ
• フ ハイジン
• シカリ ムルタザ エイ
• ヴァンガラ サルマ ヴイ
• ニマラ スリニヴァサン

Assignees

• アップル インコーポレイテッド

Dates

Publication Date

20260508

Application Date

20250402

Claims (20)

1. A base station (BS) having a processor configured to perform an operation, wherein the operation is Receiving initial data from a user device (UE) in the RRC_INACTIVE state without the UE transitioning to the RRC_CONNECTED state, While the UE is in the RRC_INACTIVE state during the active period, a physical downlink control channel (PDCCH) for UE-specific scheduling for transmitting or receiving subsequent data during the active period is transmitted. A BS comprising receiving or transmitting the subsequent data using the transmitted PDCCH based on the UE-dedicated scheduling.
2. The aforementioned processor, The BS according to claim 1, further configured to perform an operation including transmitting one or more settings for transmitting or receiving the aforementioned subsequent data.
3. The BS according to claim 2, wherein one or more of the above settings are transmitted as part of the RRC release message.
4. The BS according to claim 2, wherein one or more of the aforementioned settings are transmitted as part of a System Information Block (SIB).
5. The BS according to claim 1, wherein the UE-dedicated scheduling for the transmission or reception of the subsequent data during the active period is monitored according to a common search space.
6. The aforementioned processor, The BS according to claim 2, wherein the value of the timer for the active period is part of one or more settings, and the monitoring of the PDCCH for the transmission or reception of subsequent data is further configured to perform an operation including transmitting the value of the timer, which stops when the timer for the active period expires.
7. The aforementioned processor, Sending a radio resource control (RRC) restart message to the UE that triggers the UE to transition to the CONNECTED state, The BS according to claim 1, further configured to perform an operation including receiving an RRC restart completion message from the UE based on sending the RRC restart message.
8. The aforementioned processor, The BS according to claim 1, further configured to perform an operation including transmitting an active period start indication from the base station after the initial data transmission of the UE corresponding to the reception of the initial data from the UE, wherein the monitoring of the PDCCH for the transmission or reception of the subsequent data is stopped when the UE receives an active period stop indication.
9. The aforementioned processor, The BS according to claim 1, wherein after the initial data transmission by the UE in response to the reception of initial data from the UE, the BS is configured to perform an operation including transmitting an active period start indication to the UE, the start indication including a value for the timer of the active period, and the monitoring of the PDCCH for the transmission or reception of the subsequent data to stop when the timer of the active period expires.
10. The aforementioned processor, To send to the UE an indication to start the active period for subsequent data transmission or reception after the initial data transmission, The BS according to claim 1, further configured to perform an operation including transmitting an indication of a measurement setting associated with the UE in the RRC_INACTIVE state, which includes at least a predetermined threshold.
11. The aforementioned processor, The BS according to claim 1, wherein one or more settings for the transmission or reception of the subsequent data are further configured to perform an operation that includes transmitting one or more settings, each setting including an interruption setting for causing the UE to transition to the RRC_INACTIVE state.
12. The BS according to claim 8 or 9, wherein the initiation indication is a radio resource control (RRC) signaling, and the RRC signaling includes one or more settings for the transmission or reception of the subsequent data.
13. The aforementioned processor, The BS according to claim 1, configured to perform an operation including scrambling the PDCCH for UE-only scheduling for the transmission or reception of the subsequent data during the active period, based on the temporary cell radio network temporary identifier (TC-RNTI) type, identity RNTI (I-RNTI) type, or configured grant RNTI (CG-RNTI) type of the radio network temporary identifier (RNTI).
14. It is a method, Receiving initial data from a user device (UE) in the RRC_INACTIVE state without the UE transitioning to the RRC_CONNECTED state, While the UE is in the RRC INACTIVE state during the active period, a physical downlink control channel (PDCCH) for UE-dedicated scheduling for the transmission or reception of subsequent data during the active period is transmitted. A method comprising receiving or transmitting the subsequent data using the transmitted PDCCH based on the UE-dedicated scheduling.
15. Sending one or more settings for sending or receiving the aforementioned subsequent data, The method according to claim 14, further comprising:
16. The method according to claim 15, wherein one or more of the settings are transmitted as part of an RRC release message.
17. The method according to claim 15, wherein one or more of the settings are transmitted as part of a System Information Block (SIB).
18. The method according to claim 14, wherein the UE-dedicated scheduling for the transmission or reception of the subsequent data during the active period is monitored according to a common search space.
19. A timer value for the active period, wherein the timer value is part of one or more settings, and the monitoring of the PDCCH for the transmission or reception of subsequent data stops when the timer for the active period expires, The method according to claim 15, further comprising:
20. Sending a radio resource control (RRC) restart message to the UE that triggers the UE to transition to the CONNECTED state, Based on the transmission of the RRC restart message, the UE receives an RRC restart completion message, The method according to claim 14, further comprising:

Description

This invention relates generally to wireless technology, and more particularly to a method and apparatus for transmitting subsequent data from a base station (BS) while user equipment (UE) is in an inactive state. In wireless communication networks, 5G New Radio (NR) provides a higher capacity and faster network that can facilitate the control of Internet of Things (IoT) devices, such as remote devices, in applications where real-time network performance is critical. As the demand for faster data exchange and seamless communication increases, reducing latency and battery consumption has become crucial in supporting such demands while maintaining the performance of 5G NR technology. 5G NR supports three RRC states, including RRC CONNECTED, RRC INACTIVE, and RRC IDLE. The 5G NR protocol stack includes a control plane and a user plane, providing connectivity between the UE and the gNB or core network (CN). Regarding the control plane for the Release-15 INACTIVE state, the UE has an on-access stratum (NAS) connection to the CN. In addition, the UE does not have dedicated access stratum (AS) resources, and the UE maintains the RRC settings before entering the INACTIVE state. Regarding the user plane for the Release-15 INACTIVE state, the UE cannot perform any dedicated data transmission/reception. If the UE has dedicated data transmission/reception, the UE should enter the CONNECTED state. Specifically, in the case of DL data transmission, gNodeB pages the UE via the RAN paging mechanism, triggering the UE to enter the CONNECTED state. In the case of uplink (UL) data transmission, the UE triggers the RACH procedure to enter the CONNECTED state. Release-15 In terms of mobility for the INACTIVE state, an INACTIVE UE can move within the RNA (i.e., the RAN notification area) without notifying the NG-RAN. The cell selection/re-selection procedure is the same as for the RRC_IDLE state. There are three common state transition scenarios between the INACTIVE state and the CONNECTED state. First, the state transition from the CONNECTED state to the INACTIVE state involves RRC release with suspend information. The state transition from the INACTIVE state to the CONNECTED state involves an RRC restart procedure. The state transition from the INACTIVE state to the IDLE state involves (1) RRC release and (2) an abnormal case (inability to find a cell for camping). UEs with small and infrequent data transmissions are generally kept in the RRC_INACTIVE state by the network. Traffic from instant messaging services and smartphone applications such as push notifications from mobile applications are some examples of small and infrequent data traffic. Connection setup and subsequent release to the INACTIVE state occur for each data transmission, resulting in unnecessary power consumption and signaling overhead. Typically, uplink or downlink (downlink, DL) transmissions are accompanied by feedback transmissions in DL/UL (e.g., TCP ACK or RLC status reporting). If the UE performs the initial UL transmission and then directly returns to the INACTIVE state, the NW must perform RAN paging to trigger the UE to return to the CONNECTED state for feedback reception when the NW transmits feedback in the downlink direction. Such a procedure may negate the advantages of direct transmission in the INACTIVE state. Therefore, an extended mechanism is needed to allow the UE to continuously monitor potential network scheduling after the initial data transmission in the INACTIVE state, thereby reducing the amount of data transmission latency and signaling overhead incurred during state transitions. This extended mechanism can therefore leverage the advantages of direct transmission in the INACTIVE state. A method and apparatus from the perspective of a base station are described. In an exemplary embodiment, a base station having a processor configured to perform an operation including receiving initial data from a UE is in the RRC_INACTIVE state while the UE does not transition from the RRC_INACTIVE state to the RRC_CONNECTED state. The operation further includes transmitting a physical downlink control channel (PDCCH) for UE-dedicated scheduling for the transmission or reception of subsequent data during the active period while the UE is in the RRC_INACTIVE state. Furthermore, the operation includes receiving or transmitting the transmission of subsequent data based on the dedicated scheduling. In some embodiments, the processor is further configured to perform operations including transmitting one or more settings for the transmission or reception of subsequent data. In some embodiments, one or more settings are transmitted as part of an RRC release message. In some other embodiments, one or more settings are transmitted as part of a System Information Block (SIB). In some embodiments, the processor is further configured to perform an operation that includes sending an instruction indicating which of the settings to use for sending or receiving sub