EP-4742756-A1 - METHOD FOR EARLY CSI ACQUISITION FOR LTM SWITCHING

Abstract

A method includes receiving, by a user equipment (UE), a radio resource control (RRC) reconfiguration message from a source control unit (CU), wherein the RRC reconfiguration message includes an L1/2 Triggered Mobility (LTM) candidate configuration and/or a list of reporting configuration identifiers for early CSI acquisition; transmitting, by the UE, an RRC reconfiguration request acknowledgment to the source CU; waiting, by the UE, for a cell switch command or MAC CE; performing, by the UE, a measurement on an associated channel state information reference signal (CSI-RS); and transmitting, by the UE, a report to a target DU using the candidate configuration.

Inventors

• SELVAGANAPATHY, SRINIVASAN
• GOYAL, SANJAY
• ZHANG, XIN
• KOSKELA, TIMO

Assignees

• Nokia Technologies Oy

Dates

Publication Date

20260513

Application Date

20251014

Claims (12)

1. A method, comprising: receiving, by a user equipment (UE), a radio resource control (RRC) reconfiguration message from a source control unit (CU), wherein the RRC reconfiguration message includes an L1/2 Triggered Mobility (LTM) candidate configuration and/or a list of reporting configuration identifiers for early CSI acquisition; transmitting, by the UE, an RRC reconfiguration request acknowledgment to the source CU; waiting, by the UE, for a cell switch command or MAC CE; performing, by the UE, a measurement on an associated channel state information reference signal (CSI-RS); and transmitting, by the UE, a report to a target DU using the candidate configuration.
2. The method of claim 1, wherein the LTM candidate configuration includes a parameter that binds a candidate TCI state to an LTM CSI acquisition report identifier.
3. The method of claim 1 or claim 2, further comprising: autonomously triggering, by the UE, early measurements to the LTM candidate configuration.
4. The method of claim 1 or claim 2, further comprising: in a case where conditional LTM is configured, configuring the UE with an LTM CSI acquisition report identifier mapped to a synchronization signal block (SSB) and/or a candidate-TCI state.
5. The method of claim 4, further comprising: triggering, by the UE, on execution of conditional LTM, a corresponding report based on a beam of a candidate cell falling within the configuration of the UE.
6. The method of any of claims 1 to 5, further comprising: receiving, by the UE from a source DU, a semi-periodic report including a candidate identifier and a report identifier.
7. The method of claim 1, further comprising: receiving, by the UE from a source DU, an LTM cell switch command (CSC) MAC CE including a report identifier.
8. The method of claim 7, further comprising: decoding, by the UE, the corresponding target configuration based on receiving the report identifier in a cell switch command or MAC CE; and starting measurements, by the UE, based on a corresponding report configuration.
9. The method of claim 1, wherein the LTM candidate configuration includes: mapping between a candidate-TCI state and an early report configuration that needs to be triggered when the candidate TCI state is activated.
10. A user equipment (UE), comprising: at least one processor; and at least one memory storing instructions which, when executed by the at least one processor, causes the UE at least to: receive a radio resource control (RRC) reconfiguration message from a source control unit (CU), wherein the RRC reconfiguration message includes an L1/2 Triggered Mobility (LTM) candidate configuration and/or a list of reporting configuration identifiers for early CSI acquisition; transmit an RRC reconfiguration request acknowledgment to the source CU; wait for a cell switch command or MAC CE; performing a measurement on an associated channel state information reference signal (CSI-RS); and transmit a report to a target DU using the candidate configuration.
11. A method, comprising: receiving, at a source central unit (CU) from a target distributed unit (DU), an L1/2 Triggered Mobility (LTM) report configuration for triggering before cell-switching for early CSI acquisition for candidate cells of the target DU; and transmitting, to a source DU by the source CU, a request to provide a report configuration for triggering before cell-switching for early CSI acquisition, wherein the report configurations are a set of distinct parameters from a CSI measurement configuration of a source DU.
12. An apparatus, comprising: at least one processor; and at least one memory storing instructions which, when executed by the at least one processor, causes the apparatus at least to: receive, from a target distributed unit (DU), an L1/2 Triggered Mobility (LTM) report configuration for triggering before cell-switching for early CSI acquisition for candidate cells of the target DU; and transmit, to a source DU, a request to provide a report configuration for triggering before cell-switching for early CSI acquisition, wherein the report configurations are a set of distinct parameters from a CSI measurement configuration of a source DU.

Description

FIELD Various example embodiments relate generally to wireless networking and, more particularly, to configuration for conditional lower-layer triggered mobility (LTM). BACKGROUND Wireless networking provides significant advantages for user mobility. A user's ability to remain connected while on the move provides advantages not only for the user, but also provides greater efficiency and productivity for society as a whole. As user expectations for connection reliability, data speed, and device battery life become more demanding, technology for wireless networking must also keep pace with such expectations. Accordingly, there is continuing interest in improving wireless networking technology. SUMMARY In accordance with aspects of the disclosure, a method, includes receiving, by a user equipment (UE), a radio resource control (RRC) reconfiguration message from a source control unit (CU), wherein the RRC reconfiguration message includes an L1/2 Triggered Mobility (LTM) candidate configuration and/or a list of reporting configuration identifiers for early CSI acquisition; transmitting, by the UE, an RRC reconfiguration request acknowledgment to the source CU; waiting, by the UE, for a cell switch command or MAC CE; performing, by the UE, a measurement on an associated channel state information reference signal (CSI-RS); and transmitting, by the UE, a report to a target DU using the candidate configuration. In an aspect of the method, the LTM candidate configuration may include a parameter that binds the candidate TCI state to an LTM CSI acquisition report identifier. In an aspect of the method, the method may further include autonomously triggering, by the UE, early measurements to the LTM candidate configuration. In an aspect of the method, the method may further include, in a case where conditional LTM is configured, configuring the UE with an LTM CSI acquisition report identifier mapped to a synchronization signal block (SSB) and/or the candidate-TCI state. In an aspect of the method, the method may further include triggering, by the UE, on execution of conditional LTM, a corresponding report based on a beam of a candidate cell falling within the configuration of the UE. In an aspect of the method, the method may further include receiving, by the UE from a source DU, a semi-periodic report including a candidate identifier and a report identifier. In an aspect of the method, the method may further include receiving, by the UE from a source DU, an LTM cell switch command (CSC) MAC CE including a report identifier. In an aspect of the method, the method may further include decoding, by the UE, the corresponding target configuration based on receiving the report identifier in a cell switch command or MAC CE; and starting measurements, by the UE, based on a corresponding report configuration. In an aspect of the method, the LTM candidate configuration may include mapping between a candidate-TCI state and an early report configuration that needs to be triggered when the candidate TCI state is activated. In accordance with aspects of the disclosure, a user equipment (UE), includes at least one processor; and at least one memory storing instructions which, when executed by the at least one processor, causes the UE at least to perform a method as in any one of the foregoing methods. In accordance with aspects of the disclosure, processor-readable medium storing instructions which, when executed by at least one processor of an apparatus, cause the apparatus at least to perform a method as in any one of the foregoing methods. In accordance with aspects of the disclosure, a method, includes: transmitting to a source central unit (CU) by a target distributed unit (DU), an L1/2 Triggered Mobility (LTM) report configuration for triggering before cell-switching for early CSI acquisition for candidate cells of the target DU; transmitting, to a source DU by the source CU, a request to provide a report configuration for triggering before cell-switching for early CSI acquisition, wherein the report configurations are a set of distinct parameters from a CSI measurement configuration of a source DU. In an aspect of the method, the report configuration provided by the source CU may include a second report configuration of a candidate cell. In an aspect of the method, the report configuration may further include reporting resources of the candidate cell. In an aspect of the method, a complete report configuration provided by the target DU may be added to a radio resource control (RRC) reconfiguration message. In an aspect of the method, the report configuration may be provided by the target DU to the source CU, may be a complete report configuration, and wherein a radio resource control (RRC) reconfiguration message may include the complete report configuration. In an aspect of the method, the LTM configuration may include a plurality of LTM candidates, wherein each LTM candidate may include an LTM CSI acquisition report. In an asp