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EP-4218294-B1 - MANAGING UE INFORMATION AFTER PREPARING A CONDITIONAL MOBILITY PROCEDURE

EP4218294B1EP 4218294 B1EP4218294 B1EP 4218294B1EP-4218294-B1

Inventors

  • WU, CHIH-HSIANG

Dates

Publication Date
20260513
Application Date
20211019

Claims (15)

  1. A method (600) in a user equipment, UE (102), communicating with a radio access network, RAN (105), the method (600) comprising: receiving (602), from the RAN (105), a conditional configuration and a corresponding condition for a conditional procedure, wherein the corresponding condition is to be satisfied before the UE (102) can communicate with a candidate node of the RAN (105) using the conditional configuration; determining (604), by the UE (102), that an other condition is satisfied; after receiving (602) the conditional configuration and the corresponding condition, and in response to determining (604) that the other condition is satisfied, sending (606) UE information to the RAN (105), the UE information including one of: preferred configurations, in-device coexistence, IDC, assistance information, sidelink information, or multicast and/or broadcast service, MBS, interest information; after sending (606) the UE information to the RAN (105), determining (608), by the UE (102), that the corresponding condition is satisfied; again determining (612), by the UE (102), that the other condition is satisfied; and after determining that the corresponding condition is satisfied, and in response to again determining (612) that the other condition is satisfied, again sending (614) the UE information to the RAN (105).
  2. The method (600) of claim 1, wherein: the conditional procedure is a conditional handover; the candidate node is a candidate base station; receiving the conditional configuration and the corresponding condition includes receiving the conditional configuration and the corresponding condition from a source base station; sending the UE information to the RAN (105) includes sending the UE information to the source base station; and again sending the UE information to the RAN (105) includes sending the UE information to the candidate base station.
  3. The method (600) of claim 1, wherein: the conditional procedure is a conditional handover between distributed units, DUs (174), of a distributed base station; the candidate node is a candidate DU of the distributed base station; receiving the conditional configuration and the corresponding condition includes receiving the conditional configuration and the corresponding condition from a source DU of the distributed base station; sending the UE information to the RAN (105) includes sending the UE information to the source DU; and again sending the UE information to the RAN (105) includes sending the UE information to the candidate DU.
  4. The method (600) of claim 1, wherein: the conditional procedure is a conditional secondary node, SN, addition or change procedure; the candidate node is a candidate SN; receiving the conditional configuration and the corresponding condition includes receiving the conditional configuration and the corresponding condition from a master node, MN; sending the UE information to the RAN (105) includes sending the UE information to the MN; and again sending the UE information to the RAN (105) includes sending the UE information to the MN for forwarding to the candidate SN.
  5. The method (600) of claim 1, wherein: the conditional procedure is a conditional secondary node, SN, change procedure; the candidate node is a candidate SN; receiving the conditional configuration and the corresponding condition includes receiving the conditional configuration and the corresponding condition from a master node, MN; sending the UE information to the RAN (105) includes sending the UE information to a source SN of the RAN; and again sending the UE information to the RAN (105) includes sending the UE information to the candidate SN.
  6. The method of any one of claims 1-5, wherein the UE information includes the preferred configurations.
  7. The method of any one of claims 1-5, wherein the UE information includes the IDC assistance information.
  8. The method of claim 7, wherein the IDC assistance information indicates another communication technology that the UE is using, resources that the UE is using for the other communication technology, and/or resources that are affected by the other communication technology.
  9. The method of any one of claims 1-5, wherein the UE information includes the MBS interest information.
  10. The method of claim 9, wherein the MBS interest information indicates a service that is preferred or being used by the UE.
  11. The method of any one of claims 1-5, wherein the UE information includes the sidelink information.
  12. The method of claim 11, wherein the other condition is a condition relating to interest in sidelink communication, a request for sidelink resources, or provision of sidelink assistance information.
  13. The method of claim 12, wherein the sidelink information includes frequency information of one or more frequencies, sidelink transmission resources request information, or sidelink assistance information.
  14. The method of claim 11, wherein the other condition is a condition relating to a request to release sidelink communication, a lack of interest in sidelink communication, or a change of sidelink assistance information.
  15. A user equipment, UE, comprising hardware and configured to implement the method of any one of claims 1-14.

Description

This disclosure relates generally to wireless communications and, more particularly, to managing user equipment (UE) information (e.g., preferred configuration information) after a conditional mobility procedure (e.g., after a radio access network (RAN) has prepared a conditional handover or conditional addition/change procedure, and/or after the conditional handover or conditional addition/change procedure is triggered and/or executed). BACKGROUND This background description is provided for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure. In telecommunication systems, the Packet Data Convergence Protocol (PDCP) sublayer of the radio protocol stack provides services such as transfer of user-plane data, ciphering, integrity protection, etc. For example, the PDCP layer defined for the Evolved Universal Terrestrial Radio Access (EUTRA) radio interface (see 3GPP specification TS 36.323) and New Radio (NR) (see 3GPP specification TS 38.323) provides sequencing of protocol data units (PDUs) in the uplink direction (from a user device, also known as a user equipment (UE), to a base station) as well as in the downlink direction (from the base station to the UE). Further, the PDCP sublayer provides signaling radio bearers (SRBs) and data radio bearers (DRBs) to the Radio Resource Control (RRC) sublayer. Generally speaking, the UE and a base station can use SRBs to exchange RRC messages as well as non-access stratum (NAS) messages, and can use DRBs to transport data on a user plane. UEs can use several types of SRBs and DRBs. When operating in dual connectivity (DC), the cells associated with the base station operating as the master node (MN) define a master cell group (MCG), and the cells associated with the base station operating as the secondary node (SN) define the secondary cell group (SCG). So-called SRB1 resources carry RRC messages, which in some cases include NAS messages over the dedicated control channel (DCCH), and SRB2 resources support RRC messages that include logged measurement information or NAS messages, also over the DCCH but with lower priority than SRB 1 resources. More generally, SRB 1 and SRB2 resources allow the UE and the MN to exchange RRC messages related to the MN and embed RRC messages related to the SN, and also can be referred to as MCG SRBs. SRB3 resources allow the UE and the SN to exchange RRC messages related to the SN, and can be referred to as SCG SRBs. Split SRBs allow the UE to exchange RRC messages directly with the MN via lower layer resources of the MN and the SN. MCG DRBs use the lower-layer resources of only the MN, SCG DRBs use the lower-layer resources of only the SN, and split DRBs use the lower-layer resources of both the MCG and the SCG. DRBs terminated at the MN but using the lower-layer resources of only the SN can be referred to as MN-terminated SCG DRBs. DRBs terminated at the SN but using the lower-layer resources of only the MN can be referred to as SN-terminated MCG DRBs. As noted above, a UE in some scenarios can operate in DC by concurrently utilizing resources of multiple RAN nodes (e.g., multiple base stations or components of a distributed base station), which are interconnected by a backhaul. When these RAN nodes support different radio access technologies (RATs), this type of connectivity is referred to as Multi-Radio Dual Connectivity (MR-DC). When a UE operates in MR-DC, one base station operates as an MN that covers a primary cell (PCell), and the other base station operates as a secondary node (SN) that covers a primary secondary cell (PSCell). The UE communicates with the MN via the PCell, and with the SN via the PSCell. In other scenarios, the UE utilizes resources of only one base station at a time. One base station and/or the UE may then determine that the UE should establish a radio connection with another base station. For example, one base station can determine to hand the UE over to the second base station, and initiate a handover procedure. The 3GPP specifications TS 36.300 and TS 38.300 describe procedures for handover (also called "reconfiguration with sync") scenarios. These procedures involve messaging (e.g., RRC signaling and preparation) between RAN nodes that generally causes latency, which in turn increases the probability of failure for handover procedures. Some handover procedures do not involve triggering conditions associated with the UE, and can be referred to as "immediate" handover procedures. 3GPP specification TS 37.340 v15.7.0 describes procedures for a UE to add or change an SN in DC scenarios. These procedures involve messaging (e.g., RRC signaling and preparation) between RAN nodes. This messaging generally causes lat