# US 2022/0046500 A1 · Multi-connectivity using time division multiplexing > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2022/0046500 A1 - Document ID: US20220046500A1 - Status: Published application - Kind: A1 - Application number: 17/276,091 - Filed: 2019-09-23 - Published: 2022-02-10 - Earliest claimed: 2018-09-26 - Assignees: Apple Inc. - Applicants: Apple Inc. - Inventors: Candy YIU; Yi GUO; Jaemin HAN; Oluwaseyi OMOTERE - Web page: https://patentgrep.com/patent/US20220046500A1 ## CPC - H04W 8/24: Transfer of terminal data - H04W 76/30: Connection release - H04W 36/0058: {Transmission of hand-off measurement information, e.g. measurement reports} - H04W 36/0064: {of control information between different access points} - H04W 36/0069: {in case of dual connectivity, e.g. decoupled uplink/downlink} - H04W 36/00692: {using simultaneous multiple data streams, e.g. cooperative multipoint [CoMP], carrier aggregation [CA] or multiple input multiple output [MIMO] (allocation of physical resources in CoMP or in CA H04L5/0035)} - H04W 36/00837: {Determination of triggering parameters for hand-off} - H04W 36/0085: {Hand-off measurements} - H04W 74/0841: {with collision treatment} - H04L 27/2601: {Multicarrier modulation systems} - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract Techniques to configure a UE for time-division multiplexing (TDM)-based multi-connectivity handover with a source base station (SBS) and a target base station (TBS) include encoding UE capability information for transmission to the SBS. The UE capability information indicates the UE supports the TDM-based multi-connectivity handover. A measurement report is encoded for transmission to the SBS, the measurement report triggered based on a measurement event configured by the SBS. RRC signaling from the SBS is decoded, which includes a handover command in response to the measurement report. The handover command indicates a TDM pattern for multi-connectivity with the SBS and the TBS during the handover. UL data is encoded for transmission to the SBS. Transmission of the UL data to the SBS is time-division multiplexed with communications between the UE and the TBS during the handover based on the TDM pattern. ## Claims ### Claim at position 1 1-20. (canceled) ### Claim 21 An apparatus, comprising: a processor, wherein to configure a user equipment device (UE) for time-division multiplexing (TDM)-based multi-connectivity handover with a source base station (SBS) and a target base station (TBS), the processor is configured to cause the UE to: encode a measurement report for transmission to the SBS, the measurement report triggered based on a measurement event configured by the SBS; decode radio resource control (RRC) signaling from the SBS, the RRC signaling including a handover command in response to the measurement report encode uplink (UL) data for transmission to the SBS, wherein transmission of the UL data to the SBS is time-division multiplexed with communications between the UE and the TBS during the handover; perform a random access channel (RACH) procedure with the TBS during the handover, while maintaining connectivity with the SBS; and release the SBS only after the RACH procedure with the TBS is successfully completed. ### Claim 22 (depends on 21) The apparatus of claim 21, wherein the handover command originates from the TBS. ### Claim 23 (depends on 21) The apparatus of claim 21, wherein the processor is configured to cause the UE to: maintain connectivity with the SBS during the handover based on the handover command. ### Claim 24 (depends on 21) The apparatus of claim 21, wherein the handover command further includes a RACH resource. ### Claim 25 (depends on 24) The apparatus of claim 24, wherein the RRC signaling further includes a timer to indicate how long the RACH resource is valid. ### Claim 26 (depends on 21) The apparatus of claim 21, wherein the processor is configured to cause the UE to: decode a release command from the TBS; and release the SBS, based on the release command. ### Claim 27 (depends on 21) The apparatus of claim 21, further comprising transceiver circuitry coupled to the processor; and, one or more antennas coupled to the transceiver circuitry. ### Claim 28 A source base station (SBS), comprising: a radio; and a processor operably connected to the radio and configured to cause the SBS to: decode a measurement report from the UE, the measurement report triggered based on a measurement event configured by the SBS; encode radio resource control (RRC) signaling for transmission to the UE, the RRC signaling including a handover command in response to the measurement report and a handover acknowledgment from a target base station (TBS), wherein the handover command is associated with a time-division multiplexing (TDM)-based multi-connectivity handover; decode uplink (UL) data received from the UE, wherein transmission of the UL data is time-division multiplexed with communications between the UE and the TBS during the handover; and after successful completion of a random access channel (RACH) procedure between the UE and the TBS during the handover, release the UE. ### Claim 29 (depends on 28) The SBS of claim 28, wherein the processor is further configured to cause the SBS to: encode a handover request for transmission to the TBS. ### Claim 30 (depends on 29) The SBS of claim 29, wherein the processor is further configured to cause the SBS to: decode a handover acknowledgment from the TBS, the handover acknowledgment received in response to the handover request and including the handover command for transmission to the UE. ### Claim 31 (depends on 29) The SBS of claim 29, wherein the processor is further configured to cause the SBS to: decode a handover acknowledgment from the TBS, the handover acknowledgment received in response to the handover request. ### Claim 32 (depends on 31) The SBS of claim 31, wherein the processor is further configured to cause the SBS to: encode the RRC signaling for transmission to the UE, the RRC signaling including the handover command for multi-connectivity between the UE, the SBS, and the TBS during the handover. ### Claim 33 (depends on 29) The SBS of claim 29, wherein the processor is further configured to cause the SBS to: perform an Xn Application Protocol (XnAP) class-1 procedure with the TBS to negotiate the handover; and encode the RRC signaling for transmission to the UE, the RRC signaling including the handover command for multi-connectivity between the UE, the SBS, and the TBS during the handover. ### Claim 34 (depends on 28) The SBS of claim 28, wherein the processor is further configured to cause the SBS to: encode configuration signaling for transmission to the UE, the configuration signaling to configure the measurement event and a sub-frame timing difference (SFTD) between the UE and the TBS; and determine the SFTD based on the measurement report; and perform synchronization with the TBS based on the determined SFTD. ### Claim 35 (depends on 28) The SBS of claim 28, wherein the processor is further configured to cause the SBS to: decode the UL data received from the UE, wherein transmission of the UL data is time-division multiplexed with a RACH procedure between the UE and the TBS during the handover. ### Claim 36 A user equipment device (UE) comprising: a radio; and a processor operably connected to the radio and configured to cause the UE to: encode a measurement report for transmission to a source base station (SBS), the measurement report triggered based on a measurement event configured by the SBS; decode radio resource control (RRC) signaling from the SBS, the RRC signaling including a handover command in response to the measurement report, wherein the handover command is associated with a time-division multiplexing (TDM)-based multi-connectivity handover; encode uplink (UL) data for transmission to the SBS, wherein transmission of the UL data to the SBS is time-division multiplexed with communications between the UE and a target base station (TBS) during the TDM-based multi-connectivity handover; perform a random access channel (RACH) procedure with the TBS during the TDM-based multi-connectivity handover, while maintaining connectivity with the SBS; and release the SBS only after the RACH procedure with the TBS is successfully completed. ### Claim 37 (depends on 36) The UE of claim 36, wherein the handover command originates from the TBS and wherein to maintain connectivity with the SBS during the TDM-based multi-connectivity handover is based on the handover command. ### Claim 38 (depends on 36) The UE of claim 36, wherein the handover command further includes a RACH resource, and wherein the processor is further configured to cause the UE to: perform a RACH procedure with the TBS during the TDM-based multi-connectivity handover, using the RACH resource, wherein the RACH procedure is time-division multiplexed with the UL data transmission to the SBS. ### Claim 39 (depends on 36) The UE of claim 36, wherein the processor is further configured to cause the UE to: decode a release command from the TBS; and release the SBS, based on the release command. ### Claim 40 (depends on 36) The UE of claim 36, wherein the RRC signaling indicates how long a RACH resource is valid.