# US 12,010,739 B2 · Techniques for inter-gNB migration of distributed unit > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,010,739 B2 - Document ID: US12010739B2 - Status: Granted - Kind: B2 - Application number: 17/492,296 - Filed: 2021-10-01 - Published: 2022-04-14 - Granted: 2024-06-11 - Earliest claimed: 2020-10-09 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Naeem Akl; Karl Georg Hampel; Navid Abedini; Jianghong Luo; Luca Blessent; Junyi Li; Tao Luo - Web page: https://patentgrep.com/patent/US12010739B2 ## CPC - H04W 76/10: Connection setup - H04W 24/02: Arrangements for optimising operational condition - H04W 36/087: {between radio units of access points} - H04W 76/15: Setup of multiple wireless link connections - H04W 88/14: Backbone network devices - H04W 88/085: {Access point devices with remote components} - H04W 88/182: {Network node acting on behalf of an other network entity, e.g. proxy} - H04W 92/24: between backbone network devices - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract Present disclosure provides techniques for migrating integrated access and backhaul (IAB) nodes from the source centralized unit (CU) to a target IAB-donor-CU of a base station. Features of the present disclosure achieve such migration by configuring the IAB distributed unit (IAB-DU) to establish F1-connection (F1-C) with the target IAB-donor-CU via the source path before the user equipment (UE) context transfer occurs. To this end, the source IAB-donor-CU may initiate an F1-C establishment between IAB-node DU and target IAB-donor-CU. The source IAB-donor-CU may do so by acting or presenting as an IAB-node-DU proxy to the target IAB-donor-CU. At the same time, the source IAB-donor-CU may act or present as a target-IAB-donor-CU proxy to the IAB-node-DU. Thus, in some cases, the source IAB-donor-CU may present as both the IAB-node-DU proxy (to the target IAB-donor-CU) and as a target-IAB-donor-CU proxy (to the IAB-node-DU). ## Claims ### Claim 1 A method for wireless communications, comprising: establishing a first signaling connection between a source integrated access and backhaul (IAB) donor centralized unit (CU) with at least one IAB distributed unit (DU); establishing a second signaling connection between the source IAB-donor CU and a target IAB-donor CU; configuring the source IAB-donor CU to function as a first proxy for the at least one IAB-DU in order to transmit state information associated with the at least one IAB-DU to the target IAB-donor CU; receiving, at the source IAB-donor CU, a state update information from the target IAB-donor CU; and configuring the source IAB-donor CU to function as a second proxy for the target IAB-donor CU in transmitting the state update information to the at least one IAB-DU, wherein configuring the source IAB-donor CU to function as the second proxy for the target IAB-donor CU comprises: determining an identifier associated with the target IAB-donor CU; and representing the source IAB-donor CU as the target IAB-donor CU to the at least one IAB DU by adopting the identifier of the target IAB-donor CU for communications with the at least one IAB-DU. ### Claim 2 (depends on 1) The method of claim 1, wherein configuring the source IAB-donor CU to function as the first proxy for the at least one IAB-DU comprises: determining an identifier associated with at least one IAB-DU; and representing the source IAB-donor CU as the at least one IAB-DU to the target IAB-donor-CU by adopting the identifier of the at least one IAB-DU for communications with the target IAB-donor-CU. ### Claim 3 (depends on 1) The method of claim 1, wherein configuring the source IAB-donor CU to function as the first proxy for the at least one IAB-DU comprises: determining an identifier of an IAB-mobile terminal (IAB-MT) associated with the at least one IAB-DU; and transmitting the identifier of the IAB-MT to the target IAB-donor CU in order to proxy for the at least one IAB-DU. ### Claim 4 (depends on 1) The method of claim 1, wherein the state information associated with the at least one IAB-DU includes one or more of: a configuration of a cell served by the at least one IAB-DU, a context of a child connected to the at least one IAB-DU, a transport layer information for a connection between the IAB-donor-CU and the at least one IAB-DU, an identifier of a connection between the IAB-donor-CU and the at least one IAB-DU, or an identifier of one or more of the at least one IAB-DU, the IAB-donor-CU or a child connected to the at least one IAB-DU used on a connection between the IAB-donor-CU and the at least one IAB-DU. ### Claim 5 (depends on 1) The method of claim 1, wherein the state information associated with the at least one IAB-DU that is transmitted from the IAB-donor CU to the target IAB-donor comprises: forwarding a configuration information of the at least one IAB-DU that is received from the at least one IAB-DU at the source IAB-donor CU. ### Claim 6 (depends on 1) The method of claim 1, wherein the state information associated with the at least one IAB-DU that is transmitted from the IAB-donor CU to the target IAB-donor CU comprises: forwarding a configuration information associated with the at least one IAB-DU to the target IAB-donor CU that the source IAB-donor CU had previously transmitted to the at least one IAB-DU. ### Claim 7 (depends on 1) The method of claim 1, wherein receiving the state update information from the target IAB-donor CU comprises: receiving, at the source IAB-CU, an updated base station-CU identifier from the target IAB-CU; reconfiguring, at the source IAB-CU, a cell identity (ID) for a cell served by the at least one IAB-DU based in part on the updated base station-CU identifier received from the target IAB-CU; and generating the state update information associated based in part on the cell-ID. ### Claim 8 (depends on 1) The method of claim 1, wherein the first signaling connection between the source IAB-donor-CU and the at least one IAB-DU is one of F1-connection (F1-C) or radio resource control (RRC) connection, and wherein the second signaling connection between the source IAB-donor-CU and the target IAB-donor-CU is the F1-connection. ### Claim 9 (depends on 1) The method of claim 1, wherein the at least one IAB-DU is one of an IAB-donor-DU or an IAB-node-DU. ### Claim 10 (depends on 1) The method of claim 1, wherein the target IAB-donor CU and the at least one IAB-DU use one or both of the state information or the state update information in order to establish a transport network layer association (TNLA) directly between the target IAB-donor-CU and the at least one IAB-DU. ### Claim 11 (depends on 1) The method of claim 1, wherein the source IAB-donor-CU indicates to the at least one IAB-DU a transport network layer (TNL) endpoint for the target IAB-donor-CU to enable the at least one IAB-DU to establish a transport network layer association (TNLA) TNLA between the target IAB-donor-CU and the at least one IAB-DU. ### Claim 12 (depends on 1) The method of claim 1, wherein the IAB-donor-CU is a base station CU. ### Claim 13 An apparatus for wireless communications, comprising: at least one processor; and memory coupled to the at least one processor, the memory including instructions executable by the at least one processor to cause the apparatus to: establish a first signaling connection between a source integrated access and backhaul (IAB) donor centralized unit (CU) with at least one IAB distributed unit (DU); establish a second signaling connection between the source IAB-donor CU and a target IAB-donor CU; configure the source IAB-donor CU to function as a first proxy for the at least one IAB-DU in order to transmit state information associated with the at least one IAB-DU to the target IAB-donor CU; receive, at the source IAB-donor CU, a state update information from the target IAB-donor CU; and configure the source IAB-donor CU to function as a second proxy for the target IAB-donor CU in transmitting the state update information to the at least one IAB-DU, wherein the instructions to configure the source IAB-donor CU to function as the second proxy for the target IAB-donor CU are further executable by the at least one processor to cause the apparatus to: determine an identifier associated with the target IAB-donor CU; and represent the source IAB-donor CU as the target IAB-donor CU to the at least one IAB DU by adopting the identifier of the target IAB-donor CU for communications with the at least one IAB-DU. ### Claim 14 (depends on 13) The apparatus of claim 13, wherein the instructions to configure the source IAB-donor CU to function as the first proxy for the at least one IAB-DU are further executable by the at least one processor to cause the apparatus to: determine an identifier associated with at least one IAB-DU; and represent the source IAB-donor CU as the at least one IAB-DU to the target IAB-donor-CU by adopting the identifier of the at least one IAB-DU for communications with the target IAB-donor-CU. ### Claim 15 (depends on 13) The apparatus of claim 13, wherein the instructions to configure the source IAB-donor CU to function as the first proxy for the at least one IAB-DU are further executable by the at least one processor to cause the apparatus to: determine an identifier of an IAB-mobile terminal (IAB-MT) associated with the at least one IAB-DU; and transmit the identifier of the IAB-MT to the target IAB-donor CU in order to proxy for the at least one IAB-DU. ### Claim 16 (depends on 13) The apparatus of claim 13, wherein the state information associated with the at least one IAB-DU includes one or more of: a configuration of a cell served by the at least one IAB-DU, a context of a child connected to the at least one IAB-DU, a transport layer information for a connection between the IAB-donor-CU and the at least one IAB-DU, an identifier of a connection between the IAB-donor-CU and the at least one IAB-DU, or an identifier of one or more of the at least one IAB-DU, the IAB-donor-CU or a child connected to the at least one IAB-DU used on a connection between the IAB-donor-CU and the at least one IAB-DU. ### Claim 17 (depends on 13) The apparatus of claim 13, wherein the state information associated with the at least one IAB-DU that is transmitted from the IAB-donor CU to the target IAB-donor comprises: forwarding a configuration information of the at least one IAB-DU that is received from the at least one IAB-DU at the source IAB-donor CU. ### Claim 18 (depends on 13) The apparatus of claim 13, wherein the state information associated with the at least one IAB-DU that is transmitted from the IAB-donor CU to the target IAB-donor CU comprises: forwarding a configuration information associated with the at least one IAB-DU to the target IAB-donor CU that the source IAB-donor CU had previously transmitted to the at least one IAB-DU. ### Claim 19 (depends on 13) The apparatus of claim 13, wherein the instructions to receive the state update information from the target IAB-donor CU are further executable by the at least one processor to cause the apparatus to: receive, at the source IAB-CU, an updated base station-CU identifier from the target IAB-CU; reconfigure, at the source IAB-CU, a cell identity (ID) for a cell served by the at least one IAB-DU based in part on the updated base station-CU identifier received from the target IAB-CU; and generate the state update information associated based in part on the cell-ID. ### Claim 20 (depends on 13) The apparatus of claim 13, wherein the first signaling connection between the source IAB-donor-CU and the at least one IAB-DU is one of F1-connection (F1-C) or radio resource control (RRC) connection, and wherein the second signaling connection between the source IAB-donor-CU and the target IAB-donor-CU is the F1-connection. ### Claim 21 (depends on 13) The apparatus of claim 13, wherein the at least one IAB-DU is one of an IAB-donor-DU or an IAB-node-DU. ### Claim 22 (depends on 13) The apparatus of claim 13, wherein the target IAB-donor CU and the at least one IAB-DU use one or both of the state information or the state update information in order to establish a transport network layer association (TNLA) directly between the target IAB-donor-CU and the at least one IAB-DU. ### Claim 23 (depends on 13) The apparatus of claim 13, wherein the source IAB-donor-CU indicates to the at least one IAB-DU a transport network layer (TNL) endpoint for the target IAB-donor-CU to enable the at least one IAB-DU to establish a transport network layer association (TNLA) TNLA between the target IAB-donor-CU and the at least one IAB-DU. ### Claim 24 (depends on 13) The apparatus of claim 13, wherein the IAB-donor-CU is a base station CU. ### Claim 25 A non-transitory computer readable medium storing instructions, executable by a processor, for wireless communications, comprising instructions for: establishing a first signaling connection between a source integrated access and backhaul (IAB) donor centralized unit (CU) of a base station with at least one IAB distributed unit (DU); establishing a first signaling connection between a source integrated access and backhaul (IAB) donor centralized unit (CU) with at least one IAB distributed unit (DU); establishing a second signaling connection between the source IAB-donor CU and a target IAB-donor CU; configuring the source IAB-donor CU to function as a first proxy for the at least one IAB-DU in order to transmit state information associated with the at least one IAB-DU to the target IAB-donor CU; receiving, at the source IAB-donor CU, a state update information from the target IAB-donor CU; and configuring the source IAB-donor CU to function as a second proxy for the target IAB-donor CU in transmitting the state update information to the at least one IAB-DU, wherein configuring the source IAB-donor CU to function as the second proxy for the target IAB-donor CU further include instructions for: determining an identifier associated with the target IAB-donor CU; and representing the source IAB-donor CU as the target IAB-donor CU to the at least one IAB DU by adopting the identifier of the target IAB-donor CU for communications with the at least one IAB-DU. ### Claim 26 (depends on 25) The non-transitory computer readable medium of claim 25, wherein configuring the source IAB-donor CU to function as the first proxy for the at least one IAB-DU further include instructions for: determining an identifier associated with at least one IAB-DU; and representing the source IAB-donor CU as the at least one IAB-DU to the target IAB-donor-CU by adopting the identifier of the at least one IAB-DU for communications with the target IAB-donor-CU. ### Claim 27 An apparatus for wireless communications, comprising: means for establishing a first signaling connection between a source integrated access and backhaul (IAB) donor centralized unit (CU) with at least one IAB distributed unit (DU); means for establishing a second signaling connection between the source IAB-donor CU and a target IAB-donor CU; means for configuring the source IAB-donor CU to function as a first proxy for the at least one IAB-DU in order to transmit state information associated with the at least one IAB-DU to the target IAB-donor CU; means for receiving, at the source IAB-donor CU, a state update information from the target IAB-donor CU; and means for configuring the source IAB-donor CU to function as a second proxy for the target IAB-donor CU in transmitting the state update information to the at least one IAB-DU, wherein means for configuring the source IAB-donor CU to function as the second proxy for the target IAB-donor CU comprises: means for determining an identifier associated with the target IAB-donor CU; and means for representing the source IAB-donor CU as the target IAB-donor CU to the at least one IAB DU by adopting the identifier of the target IAB-donor CU for communications with the at least one IAB-DU.