JP-2026514457-A - Beam index for Layer 1/Layer 2 trigger mobility (LTM)

Abstract

Apparatus and methods for beam indices for Layer 1/Layer 2 trigger mobility (LTM) are disclosed. Advantages of the apparatus/method include reduced cell switching latency. In one embodiment, a user apparatus (UE) receives a medium access control element (MAC-CE) from a serving cell, which includes an index for a candidate cell and the activation of one or more transmit configuration indicator (TCI) states for the candidate cell. The UE further receives a cell switching command from the serving cell via lower-layer signaling, indicating the candidate cell as the target cell. In response to the cell switching command, the UE further switches communication with the serving cell to communication with the target cell, which includes communicating with the target cell by applying at least one of one or more TCI states. [Selection Diagram] Figure 5

Inventors

• コスケラ，ティモ
• ゴヤル，サンジャイ
• ラドゥ，キース サリヤ ジャヤシンゲ

Assignees

• ノキア テクノロジーズ オサケユイチア

Dates

Publication Date

20260511

Application Date

20240207

Priority Date

20230405

Claims (20)

1. At least one processor, A user device comprising at least one memory for storing instructions, wherein the instructions are executed by at least one of the processors, at least, The steps include receiving from a serving cell an index of a candidate cell and a media access control element (MAC-CE) which includes activating one or more transmit configuration indicator (TCI) states for the candidate cell, The steps include receiving a cell switching command from the serving cell via lower-layer signaling, indicating the candidate cell as the target cell, A user device that, in response to the cell switching command, causes the user device to perform a step of switching communication with the serving cell to communication with the target cell, wherein the communication with the target cell includes communication with the target cell to which at least one of one or more TCI states is applied.
2. The user device according to claim 1, characterized in that the MAC-CE includes a first field and a second field indicating whether the information in the first field is for the serving cell or for the candidate cell.
3. The user device according to claim 1, characterized in that the MAC-CE includes a first value and a second value indicating that the first value identifies the candidate cell.
4. The user device according to claim 1, characterized in that the MAC-CE includes a list of candidate cell-specific TCI states representing one or more of the TCI states.
5. The user device according to claim 1, characterized in that the cell switching command further includes a reference to at least one of the one or more TCI states.
6. When the instruction is executed by at least one of the processors, at least, The user device according to claim 1, characterized in that the user device further causes the user device to perform the step of receiving the cell switching command by receiving downlink control information (DCI) which includes an index of the candidate cell and a TCI code point that refers to at least one of one or more TCI states.
7. When the instruction is executed by at least one of the processors, at least, The user device according to claim 1, characterized in that the user device further causes the user device to perform the step of receiving the cell switching command by receiving downlink control information (DCI) which includes an index of a candidate cell activation TCI list including the candidate cell and a TCI code point that refers to at least one of one or more TCI states.
8. When the instruction is executed by at least one of the processors, at least, The user device according to claim 1, further causing the user device to perform the step of receiving the cell switching command by receiving downlink control information (DCI) which includes a reference to at least one of the one or more TCI states and an indicator that at least one of the one or more TCI states is for the candidate cell.
9. When the instruction is executed by at least one of the processors, at least, The user equipment device according to claim 1, further characterized in that it causes the user equipment device to perform the step of performing intra-cell beam management in the target cell based on one or more of the TCI states.
10. One or more of the TCI states are associated with a plurality of physical cell identifiers (PCIs), When the instruction is executed by at least one of the processors, at least, The user equipment device according to claim 1, further characterized in that the user equipment device is made to perform the step of performing at least one of intra-cell beam management or inter-cell beam management in the target cell based on one or more TCI states.
11. When the instruction is executed by at least one of the processors, at least, The user device according to claim 1, further characterized in that the user device is made to perform the step of maintaining the TCI state list activated by the serving cell while operating in the target cell.
12. When the instruction is executed by at least one of the processors, at least, The user device is further instructed to perform the step of transmitting an indicator of the user device's capabilities. The user device according to claim 1, wherein at least one of the number of one or more TCI states activated in the MAC-CE for the candidate cell, or the number of TCI states activated across a plurality of cells in the user device, is based on the user device capability.
13. A method performed by a user device, The steps include receiving from a serving cell an index of a candidate cell and a media access control element (MAC-CE) which includes activating one or more transmit configuration indicator (TCI) states for the candidate cell, The steps include receiving a cell switching command from the serving cell via lower-layer signaling, indicating the candidate cell as the target cell, A method characterized by comprising the step of switching communication with the serving cell to communication with the target cell in response to the cell switching command, wherein the communication with the target cell includes communication with the target cell in which at least one of the one or more TCI states is applied.
14. The method according to 13, characterized in that the MAC-CE includes a first field and a second field indicating whether the information in the first field is for the serving cell or for the candidate cell.
15. The method according to 13, characterized in that the MAC-CE includes a first value and a second value indicating that the first value identifies the candidate cell.
16. The method according to 13, characterized in that the MAC-CE includes a list of candidate cell-specific TCI states representing one or more of the TCI states.
17. The method according to 13, characterized in that the cell switching command further includes a reference to at least one of the one or more TCI states.
18. One or more of the TCI states are associated with a plurality of physical cell identifiers (PCIs), The method according to 13, further comprising the step of performing at least one of intra-cell management or inter-cell management in the target cell based on one or more TCI states.
19. Further steps include sending UE capability indicators, The method according to 13, characterized in that at least one of the number of TCI states activated in the MAC-CE for the candidate cell, or the number of TCI states activated across a plurality of cells in the user equipment, is based on the UE capability.
20. At least one processor, A network device comprising at least one memory for storing instructions, wherein the instructions are executed by at least one of the processors, at least, The steps include transmitting a media access control element (MAC-CE) to a user device, which includes an index of a candidate cell and activating one or more Transmit Configuration Indicator (TCI) states for the candidate cell, The steps include sending a cell switching command indicating the candidate cell as the target cell to the user device via lower-layer signaling, A network device characterized by causing the network device to perform the steps of: responding to the cell switching command, and performing a handover of the user equipment to the target cell.

Description

Various exemplary embodiments relate generally to wireless networking, and more specifically to beam indices for Layer 1/Layer 2 trigger mobility (LTM) in wireless networking. Wireless networking offers significant advantages to user mobility. The ability for users to stay connected while on the move not only benefits the user but also contributes to greater efficiency and productivity for society as a whole. As user expectations for connection reliability, data speed, and device battery life become more stringent, wireless networking technologies must also meet those expectations. Therefore, there remains considerable interest in improving wireless networking technologies. According to aspects of this disclosure, the user device includes at least one processor and at least one memory. The at least one memory, which stores instructions, causes the user device to perform at least the following steps when an instruction is executed by at least one processor: receiving a media access control element (MAC-CE) from a serving cell, which includes an indicator of a candidate cell and the activation of one or more transmit configuration indicator (TCI) states for the candidate cell; receiving a cell switching command from the serving cell via lower-layer signaling, indicating the candidate cell as the target cell; and, in response to the cell switching command, switching communication with the serving cell to communication with the target cell, wherein communication with the target cell includes communicating with the target cell by applying at least one of one or more TCI states. In some aspects of this disclosure, the MAC-CE may include a first field and a second field indicating whether the information in the first field is for a serving cell or a candidate cell. In some aspects of this disclosure, MAC-CE may include a first value and a second value indicating that the first value identifies a candidate cell. In some aspects of this disclosure, MAC-CE may include a candidate cell-specific TCI state list containing one or more TCI states. In some aspects of this disclosure, a cell switching command may further include a reference to at least one of one or more TCI states. In one aspect of this disclosure, when an instruction is executed by at least one processor, the user device may further perform the step of receiving at least a cell switching command by receiving downlink control information (DCI) which includes at least an index of a candidate cell and a TCI code point that refers to at least one of one or more TCI states. In one aspect of this disclosure, when an instruction is executed by at least one processor, the user device may further perform the step of receiving a cell switching command by receiving downlink control information (DCI) which includes at least an index of a candidate cell activation TCI list containing candidate cells and a TCI code point referencing at least one of one or more TCI states. In one aspect of this disclosure, the instruction may, when executed by at least one processor, cause a user device to further perform the step of receiving a cell switching command by receiving downlink control information (DCI) which includes at least a reference to at least one of one or more TCI states and an indicator that at least one of one or more TCI states is for a candidate cell. In one aspect of this disclosure, the instruction may, when executed by at least one processor, cause a user equipment to further perform at least intra-cell beam management in a target cell based on one or more TCI states. In one aspect of this disclosure, one or more TCI states are associated with a plurality of physical cell identifiers (PCIs), and the instruction, when executed by at least one processor, can cause a user equipment to further perform the step of performing at least one of intra-cell beam management or inter-cell beam management in a target cell based on one or more TCI states. In one aspect of this disclosure, an instruction, once executed by at least one processor, may cause a user device to further perform the step of maintaining a TCI state list activated by the serving cell, at least while operating in the target cell. In one aspect of this disclosure, when an instruction is executed by at least one processor, the instruction includes at least the step of transmitting an indicator of user device capability, wherein at least one of one or more TCI states activated in the MAC-CE for a candidate cell or a number of TCI states activated across multiple cells in the user device may cause the user device to further perform steps based on user device capability. A method is provided, according to aspects of this disclosure, that can be performed by a user device. The method includes: receiving a media access control element (MAC-CE) from a serving cell, which includes an index of a candidate cell and the activation of one or more transmit configuration indicator (TCI) states for the candidate cell;