Network-triggered inter-cell mobility

Abstract

In wireless communication, devices may change, add, or handover between cells of network access for inter-cell mobility. This may involve Layer 1 and / or Layer 2 (L1 / L2) signaling for a user equipment (UE) moving between cells in a network. The signaling can reduce mobility interruption time and improve handover robustness. The movement may be triggered by the network or the UE. Layer 1 and / or Layer 3 (L1 / L3) measurements are utilized for inter-cell mobility. The mobility may be coordinated based on interactions between a centralized unit (CU) and a distributed unit (DU). This procedure can reduce interruption time and improve reliability.

Description

Technical Field

[0001] This specification generally relates to wireless communication. More specifically, in a mobile device communication system, improved signaling for inter-cell mobility is possible.

Background Art

[0002] Wireless communication technology is leading the world towards a more connected and networked society. Wireless communication depends on efficient network resource management and allocation between user mobile stations and wireless access network nodes (including but not limited to wireless base stations). Next-generation networks are expected to provide high-speed, low-latency, and ultra-reliable communication functions to meet the requirements from various industries and users. User mobile stations or user equipment (UE) are becoming more complex, and the amount of data to be communicated is continuously increasing. To improve communication, meet the reliability requirements of vertical industries, and support next-generation network services, communication should be improved.

Summary of the Invention

Problems to be Solved by the Invention

[0003] This specification relates to methods, systems, and apparatuses for layer 1 and / or layer 2 (L1 / L2) signaling for user equipment (UE) moving between cells within a network. The signaling can shorten the mobility interruption time and improve the robustness of handover. The movement may be triggered by the network or the UE. Layer 1 and / or layer 3 (L1 / L3) measurements are utilized for inter-cell mobility. The mobility may be coordinated based on the interaction between a centralized unit (CU) and a distributed unit (DU).

Means for Solving the Problems

[0004] In one embodiment, the wireless communication method includes receiving a configuration message that includes a plurality of candidate cells, each having settings and cell identification ("ID:identification") information; transmitting a measurement report for at least one of the candidate cells, including at least one of a Layer 1 ("L1") measurement or a Layer 3 ("L3") measurement; receiving a command that identifies at least one of the candidate cells based on the measurement report; and transmitting a communication to the identified at least one candidate cell based on the command and the settings of the identified candidate cell.

[0005] Measurement reports and communications are transmitted from the user equipment ("UE") to the base station. The UE receives configuration messages and commands from the base station. These commands are Layer 1 or Layer 2 ("L1 / L2") signaling, and communications transmitted to the identified candidate cell are L1 / L2 signaling. Here, L1 signaling includes at least one of downlink control information ("DCI"), uplink control information ("UCI"), or physical layer acknowledgment ("ACK") signaling, and L2 signaling includes a medium access control element ("MAC CE"). These commands include cell ID information of the identified candidate cell that is to be activated. Cell ID information includes at least one of the following: candidate cell configuration index, serving cell ID, physical cell identity ("PCI"), PCI and frequency, reference signal ("RS") ID associated with the candidate cell, or transmission configuration indicator ("TCI") status ID associated with the candidate cell. A candidate cell includes separate lists for any of the candidate cells configured as special cells ("SpCell") or any of the candidate cells configured as secondary cells ("SCell"), and identification is based on these separate lists. A candidate cell includes a list in which each candidate cell can be configured as a special cell ("SpCell") or a secondary cell ("SCell"). A candidate cell includes a list in which each cell can be configured as a candidate cell for both special cells ("SpCell") and secondary cells ("SCell").Measurement reports are triggered by the UE based on conditions including at least one of the following: an event met based on Layer 1 measurements of at least one candidate cell, an out-of-sync indication from a serving cell or special cell ("SpCell"), or a failure of a serving cell or SpCell. This command includes at least one of the following: the timing advance ("TA") value or compensated TA value of the identified candidate cell; the cell radio network temporary identifier ("C-RNTI") of the identified candidate cell; the activated DL / UL bandwidth part ("BWP") ID of the identified candidate cell; the initial TCI state of the identified candidate cell; the serving cell ID of the identified candidate cell; an instruction indicating whether the RACH procedure to the identified candidate cell is skipped; an instruction indicating whether the UE maintains a connection with the current serving cell; an instruction indicating whether the identified candidate cell is activated as a special cell ("SpCell"); and an instruction indicating whether PDCP duplication is activated after accessing the identified candidate cell.

[0006] The method further includes activating a stored cell configuration of an identified candidate cell, applying a stored cell configuration of an identified candidate cell, or performing mobility from the current serving cell to the identified candidate cell. The method further includes starting a timer for activation or mobility. The timer is a media access control (MAC) layer timer or a radio resource control (RRC) layer timer. The timer is stopped based on a condition including at least one of the following: a successful transmission of communication to the identified candidate cell, a failure of the current serving cell, or information from a higher layer indicating that the timer has stopped. The method further includes determining failure for the activation or mobility based on the expiration of the timer. The method further includes reporting a failure for the activation or mobility to the base station, wherein the failure is reported via MAC CE or RRC signaling; notifying a higher layer of the failure for the activation or mobility; or selecting another cell from the candidate cells and performing another activation of the selected cell or performing another mobility to the selected cell. The method further includes activating the identified candidate cell, wherein if the identified candidate cell is activated as a primary cell ("PCell"), the serving cell identification information is set to zero; if the identified candidate cell is activated as a secondary cell ("SCell") or a primary secondary cell ("PSCell"), the serving cell identification information is set based on the received identification information for the identified candidate cell. The method further includes receiving a message from the base station and, based on the receipt of the message, removing the stored candidate cell setting.The method further includes receiving a message from the base station containing at least one indicator to remove all stored candidate cell settings or some of the candidate cells, and removing the stored candidate cell settings based on the indicator or the indicated candidate cells to be removed. The message is at least one of a handover command, a primary / secondary cell ("PSCell") add or / modify command, or a message instructing the release or suspension of a radio resource control ("RRC") connection. The method further includes receiving a message from the base station to resume a suspended radio resource control ("RRC") connection, the message containing one or more candidate cells to be resumed, activated, maintained, or restored. A candidate cell refers to a candidate cell group, where the candidate cell group is at least one of a candidate master cell group ("MCG") or a candidate secondary cell group ("SCG").

[0007] In another embodiment, the wireless communication method includes transmitting a configuration message containing a plurality of candidate cells, each having settings and cell identification (ID) information; receiving a measurement report for at least one of the candidate cells, containing at least one Layer 1 ("L1") measurement or Layer 3 ("L3") measurement; transmitting a command to identify at least one of the candidate cells based on the measurement report; and receiving a communication in the identified at least one candidate cell based on the command and the settings of the identified candidate cell. The configuration message and command are transmitted from the base station to the user equipment ("UE"), where the base station receives the measurement report and the communication from the UE. This command is Layer 1 or Layer 2 ("L1 / L2") signaling, and the communication received in the identified candidate cell is L1 / L2 signaling, where L1 signaling includes at least one of downlink control information ("DCI"), uplink control information ("UCI"), or physical layer acknowledgment ("ACK") signaling, and L2 signaling includes a medium access control element ("MAC CE"). This command includes cell ID information for the identified candidate cell that is to be activated. The cell ID information includes at least one of the candidate cell configuration index, serving cell ID, physical cell identity ("PCI"), PCI and frequency, reference signal ("RS") ID associated with the candidate cell, or transmission configuration indicator ("TCI") status ID associated with the candidate cell. Candidate cells include separate lists for any of the candidate cells to be set as special cells ("SpCell") or any of the candidate cells to be set as secondary cells ("SCell"), and identification is performed based on these separate lists.The candidate cell list contains a list in which each cell can be set as either a special cell ("SpCell") or a secondary cell ("SCell"). The candidate cell list contains a list in which each cell can be set as a candidate cell for both special cells ("SpCell") and secondary cells ("SCell"). This command includes at least one of the following: the timing advance ("TA") value or compensated TA value of the identified candidate cell; the cell radio network temporary identifier ("C-RNTI") of the identified candidate cell; the activated DL / UL bandwidth part ("BWP") ID of the identified candidate cell; the initial TCI state of the identified candidate cell; the serving cell ID of the identified candidate cell; an instruction indicating whether the RACH procedure to the identified candidate cell is skipped; an instruction indicating whether the UE maintains a connection with the current serving cell; an instruction indicating whether the identified candidate cell is activated as a SpCell; and an instruction indicating whether PDCP duplication is activated after accessing the identified candidate cell.

[0008] The method further includes sending a message to the UE that includes at least one of an indicator to remove all stored candidate cell settings, or a group of candidate cells to be removed. The UE removes the stored candidate cell settings based on the indicator or the group of candidate cells to be removed. The message is at least one of a handover command, a primary / secondary cell ("PSCell") add or / modify command, or a message instructing the release or suspension of a radio resource control ("RRC") connection. The method further includes sending a message to the UE to resume a suspended RRC connection, where the message includes at least one of a candidate cell to be resumed, activated, maintained, or restored. A candidate cell refers to a candidate cell group, where a candidate cell group is at least one of a candidate master cell group ("MCG") or a candidate secondary cell group ("SCG").

[0009] In another embodiment, a wireless communication method includes receiving a configuration message containing a plurality of candidate cells having configuration, cell identification ("ID") information and one or more execution conditions; evaluating the execution conditions for the candidate cells to identify at least one of the candidate cells; and transmitting a communication to the identified at least one candidate cell based on the configuration of that candidate cell. The communication is transmitted from a user device ("UE") to a base station, where the UE receives a configuration message from the base station and evaluates the execution conditions. The communication to the identified at least one candidate cell is Layer 1 or Layer 2 ("L1 / L2") signaling, where L1 signaling includes at least one of downlink control information ("DCI"), uplink control information ("UCI"), and physical layer acknowledgment ("ACK") signaling, and L2 signaling further includes a medium access control element ("MAC CE"). The evaluation includes comparing the measurement results of candidate cells with the execution conditions, wherein at least one identified candidate cell satisfies the execution conditions. The execution conditions include at least one of the following: a list of measurement setting identifier information indicating the execution conditions, a measurement event based on an L1 measurement for the candidate cell, or a measurement event based on an L3 measurement for the candidate cell. The setting message includes at least one of the following: information indicating that multiple candidate cells can be identified together, or at least one execution condition for identifying multiple candidate cells together. The communication includes cell ID information of at least one identified candidate cell, or information indicating which of the candidate cells have already been identified together.Cell ID information includes at least one of the following: candidate cell configuration index, serving cell ID, physical cell identity ("PCI"), PCI and frequency, reference signal ("RS") ID associated with the candidate cell, or transmission configuration indicator ("TCI") status ID associated with the candidate cell. Transmission of communications to at least one identified candidate cell is based on conditions including at least one of the following: a desynchronization instruction from a serving cell or special cell ("SpCell"), or a failure of a serving cell or SpCell. Candidate cells include separate lists for any of the candidate cells configured as special cells ("SpCell") and any of the candidate cells configured as secondary cells ("SCell"), and identification is based on these separate lists. Candidate cells include a list in which each candidate cell can be configured as a special cell ("SpCell") or a secondary cell ("SCell"). The candidate cell contains a list in which each candidate cell can be set as a candidate cell for both a special cell ("SpCell") and a secondary cell ("SCell").

[0010] The method further includes activating a stored cell configuration of at least one identified candidate cell, applying a stored cell configuration of at least one identified candidate cell, or performing mobility from the current serving cell to at least one identified candidate cell. The method further includes starting a timer for activation or mobility, the timer being a media access control (MAC) layer timer or a radio resource control (RRC) layer timer. The timer is stopped based on a condition including at least one of the following: a successful transmission of communication to at least one identified candidate cell, a failure of the current serving cell, or information from a higher layer indicating the timer has stopped. The method further includes determining failure for the activation or mobility based on the expiration of the timer. The method further includes reporting a failure for the activation or mobility to the base station, wherein the failure is reported via MAC CE or RRC signaling; notifying a higher layer of the failure for the activation or mobility; or selecting another cell from among the stored candidate cells and performing another activation of the selected cell or performing another mobility to the selected cell. The method further includes activating the identified at least one candidate cell, wherein if the identified at least one candidate cell is activated as a primary cell ("PCell"), the serving cell identification information is set to zero; if the identified at least one candidate cell is activated as a secondary cell ("SCell") or a primary secondary cell ("PSCell"), the serving cell identification information is set based on the received identification information for the identified at least one candidate cell. The method further includes receiving a message from the base station and, based on the receipt of the message, removing the stored candidate cell settings.The method further includes receiving a message from a base station that includes at least one of an indicator to remove all stored candidate cell settings, or a plurality of candidate cells to be removed, and removing the stored candidate cell settings based on the indicator, or the indicated candidate cell to be removed. The message is at least one of a handover command, a primary / secondary cell ("PSCell") add or / modify command, or a message instructing the release or suspension of a radio resource control ("RRC") connection. The method further includes receiving a message from the base station to resume a suspended RRC connection, wherein the message includes at least one of a candidate cell to be resumed, activated, maintained, or restored. The candidate cell includes a candidate cell group that is at least one of a candidate master cell group ("MCG") or a candidate secondary cell group ("SCG").

[0011] In another embodiment, the wireless communication method includes transmitting a configuration message containing a plurality of candidate cells having settings, cell identification ("ID") information, and one or more execution conditions, and receiving the communication in one identified candidate cell among the candidate cells, which is identified based on an evaluation of the candidate cells and their configurations. The configuration message is transmitted from the base station to the user equipment ("UE"), where the communication is received from the UE in the identified candidate cell of the base station. The communication is Layer 1 or Layer 2 ("L1 / L2") signaling, where the L1 signaling includes at least one of downlink control information ("DCI"), uplink control information ("UCI"), and physical layer acknowledgment ("ACK") signaling, and the L2 signaling further includes a medium access control element ("MAC CE"). Communication is received in an identified candidate cell based on conditions including at least one of the following: the identified candidate cell satisfies a trigger condition, an event triggered by a desynchronization instruction from a serving cell or special cell ("SpCell"), or a failure of the serving cell or SpCell. The execution condition includes at least one of the following: a list of measurement setting identifier information indicating the execution condition, a measurement event based on an L1 measurement for the candidate cell, or a measurement event based on an L3 measurement for the candidate cell. The configuration message includes at least one of the following: information indicating that multiple candidate cells can be identified together, or the execution condition for identifying multiple candidate cells together. Communication includes cell ID information of the identified candidate cell, or information indicating that multiple candidate cells have already been identified together.Cell ID information includes at least one of the following: candidate cell configuration index, serving cell ID, physical cell identity ("PCI"), PCI and frequency, reference signal ("RS") ID associated with the candidate cell, or transmission configuration indicator ("TCI") status ID associated with the candidate cell. A candidate cell includes separate lists for any of the candidate cells to be configured as special cells ("SpCell") or as secondary cells ("SCell"), and identification is based on these separate lists. A candidate cell includes a list in which each cell can be configured as a candidate special cell (SpCell) or a candidate secondary cell (SCell). A candidate cell includes a list in which each candidate cell can be configured as a candidate cell for both special cells (SpCell) and secondary cells (SCell).

[0012] The method further includes sending a message to the UE that includes at least one of an indicator to remove all stored candidate cell settings, or a list of candidate cells to be removed, the UE then removes the stored candidate cell settings based on the indicator or the indicated list of candidate cells to be removed. The message is at least one of a handover command, a primary / secondary cell ("PSCell") add or / modify command, or a message instructing the release or suspension of an RRC connection. The method further includes sending a message to the UE to resume a suspended RRC connection, the message including one or a list of candidate cells to be resumed, activated, maintained, or restored. A candidate cell refers to a candidate cell group, where the candidate cell group is at least one of a candidate master cell group ("MCG") or a candidate secondary cell group ("SCG").

[0013] In another embodiment, a wireless communication method includes sending a request message from a centralized unit ("CU") to a distributed unit ("DU"), including a plurality of candidate cells, requesting the DU to configure at least one of the candidate cells for mobility based on Layer 1 or Layer 2 ("L1 / L2") signaling ("L1 / L2 mobility"), and the CU receiving a response message from the DU, including a list of already configured candidate cells used to identify at least one of the candidate cells, and a configuration for each of the candidate cells. The request message includes at least one of the following: an instruction that a procedure is initiated for L1 / L2 mobility, or an instruction that a procedure is initiated for a type of L1 / L2 mobility of a certain type. The type of L1 / L2 mobility includes at least one of network-triggered mobility, CU-triggered mobility, DU-triggered mobility, or user equipment ("UE")-triggered mobility.

[0014] The method further includes the CU sending one or more trigger events to the DU that can trigger the L1 / L2 mobility. The method further includes the CU receiving one or more trigger events from the DU that can trigger the L1 / L2 mobility. The method further includes the CU sending the configuration message to the DU to be sent to the UE, the configuration message comprising at least one of the following: a list of candidate cells, at least one identified from the candidate cells, a setting for each of the candidate cells, or one or more execution conditions for each of the candidate cells; and receiving confirmation of the configuration message from the UE via the DU. The method further includes the CU sending at least one of the candidate cells to the DU to request the DU to activate the candidate cell via the L1 / L2 mobility. The DU transmits L1 / L2 signaling to the UE to indicate at least one of the candidate cells to be activated via the L1 / L2 mobility.

[0015] The method further includes receiving at least one of the candidate cells from the DU at the CU to identify the at least one of the candidate cells that has already been successfully activated via the L1 / L2 mobility. The DU receives L1 / L2 signaling from the UE to identify that at least one of the candidate cells has already been successfully activated via the L1 / L2 mobility. The method further includes sending an instruction from the CU to the DU to indicate to the DU to stop transmitting L1 / L2 signaling to trigger the L1 / L2 mobility. The method further includes sending an instruction from the CU to the DU to indicate to the DU to restart transmitting L1 / L2 signaling to trigger the L1 / L2 mobility. The CU and DU are part of a base station for communicating with user equipment ("UE"), and the L1 / L2 signaling is communicated with the UE. The CU provides upper-layer support including the PDCP and RRC layers, and the DU provides lower-layer support including the RLC, MAC and physical layers, with one or more DUs configured to link with one shared CU.

[0016] In another embodiment, a wireless communication method includes receiving a request message from a centralized unit ("CU") in a distributed unit ("DU") that includes a plurality of candidate cells, requesting the DU to configure at least one of the candidate cells for mobility based on Layer 1 or Layer 2 ("L1 / L2") signaling ("L1 / L2 mobility"), and the DU sending a response message to the CU that includes a list of candidate cells used to identify at least one of the candidate cells that has already been configured, and the configuration for each of the candidate cells. The request message includes at least one of the following: an instruction that a procedure is initiated for L1 / L2 mobility, or an instruction that a procedure is initiated for a type of L1 / L2 mobility of a certain type. The type of L1 / L2 mobility includes at least one of the following: mobility triggered by a network ("NW"), mobility triggered by a CU, mobility triggered by a DU, or mobility triggered by a user device ("UE").

[0017] The method further includes the DU receiving from the CU one or more trigger events that can trigger the L1 / L2 mobility. The method further includes the DU transmitting from the CU one or more trigger events that can trigger the L1 / L2 mobility. The method further includes the DU receiving from the CU a setup message for the L1 / L2 mobility, the setup message comprising at least one of the following: a list of candidate cells, at least one identified from the candidate cells, a setting for each of the candidate cells, or one or more execution conditions for each of the candidate cells; transmitting the setup message for the L1 / L2 mobility from the DU to the UE; the DU receiving an acknowledgment of the setup message from the UE; and transmitting an acknowledgment of the setup message from the DU to the CU. The method further includes the DU receiving at least one of the candidate cells from the CU and requesting the DU to activate the candidate cell via the L1 / L2 mobility. The method further includes transmitting an L1 / L2 signaling from the DU to the UE to indicate at least one of the candidate cells to be activated via the L1 / L2 mobility. The method further includes receiving an L1 / L2 signaling in the DU from the UE to identify at least one of the candidate cells that has already been successfully activated via the L1 / L2 mobility. The method further includes transmitting at least one of the candidate cells from the DU to the CU to identify at least one of the candidate cells that has already been successfully activated via the L1 / L2 mobility. The method further includes receiving an instruction from the CU in the DU that the DU should stop transmitting an L1 / L2 signaling to trigger the L1 / L2 mobility, and stopping the transmission of an L1 / L2 signaling from the DU to the UE to trigger the L1 / L2 mobility.The method further includes the DU receiving an instruction from the CU indicating that the DU should restart the transmission of L1 / L2 signaling to trigger the L1 / L2 mobility, and restarting the transmission of the L1 / L2 signaling from the DU to the UE to trigger the L1 / L2 mobility. The CU and DU are part of a base station for communicating with user equipment ("UE"), and L1 / L2 signaling is communicated with the UE. The CU provides upper layer support including the PDCP and RRC layers, and the DU provides lower layer support including the RLC, MAC and physical layers, and one or more DUs are configured to link with a shared CU.

[0018] In another embodiment, a wireless communication method includes receiving a configuration message that includes a plurality of candidate cells, each having a configuration for each of the candidate cells, and a measurement configuration for at least one of the candidate cells, and performing a measurement on the at least one candidate cell based on the measurement configuration. The method further includes receiving a command that identifies at least one of the candidate cells based on the measurement, and triggering Layer 1 or Layer 2 ("L1 / L2") mobility from the current serving cell to the identified candidate cell based on the command and the configuration of the identified candidate cell. The method further includes evaluating the measurement for the candidate cell to identify at least one of the candidate cells, and triggering Layer 1 or Layer 2 ("L1 / L2") movement from the current serving cell to the identified candidate cell based on an evaluation of whether the measurement of the identified candidate cell satisfies the execution conditions included in the configuration message for each of the candidate cells and the configuration of the identified candidate cell. Performing a measurement, evaluating a measurement, or triggering L1 / L2 mobility is performed in a device ("UE").

[0019] Furthermore, the UE receives configuration messages or commands from the base station. The measurement configuration includes at least one Layer 1 ("L1") measurement configuration or Layer 3 ("L3") measurement configuration for at least one of the candidate cells or an adjacent cell.

[0020] The L1 measurement configuration includes a reference signal ("RS") resource for each candidate cell or adjacent cell. The RS resource includes RS resource identification information and at least one of a synchronization signal block ("SSB") resource, a channel state information reference signal ("CSI-RS") resource, or a temporary reference signal ("TRS") resource. The RS resources for a candidate cell or adjacent cell are configured within a set of RS resources for the current serving cell, or through a separate structure for listing RS resources for candidate cells or adjacent cells. The L1 measurement configuration includes a threshold for the L1 Reference Signal Received Power ("RSRP") measurement of the serving cell to control the L1 measurement for the candidate cell or adjacent cell. The method further includes the UE performing an L1 measurement for the candidate cell or adjacent cell if it is determined that the L1 RSRP measurement result for the serving cell has fallen below the threshold.

[0021] An L1 measurement configuration includes a reporting configuration for triggering a measurement report based on an L1 measurement of a candidate cell or an adjacent cell. Here, the reporting configuration includes a reporting configuration identifier and an identifier report type. The measurement report type includes the type of report triggered based on a measurement report event. The measurement report event includes the L1 measurement of an adjacent cell being better than a threshold, the L1 measurement of an adjacent cell being better than the L1 measurement of the serving cell with an offset, the L1 measurement of the serving cell being worse than a first threshold and the L1 measurement of an adjacent cell being better than a second threshold, or the L1 measurement of the serving cell being worse than a first threshold and the L3 measurement of an adjacent cell being better than a second threshold. The method further includes triggering the measurement report based on comparing whether a measurement of at least one of the candidate cells or adjacent cells satisfies at least one of the measurement report events. The method further includes receiving a second command that identifies at least one of the at least one RS resource identification information or the at least one cell identification information of the candidate cell or the adjacent cell. The method further includes performing the measurement based on the identified RS resource identification information or the cell identification information of the candidate cell or the adjacent cell, or reporting the measurement based on the identified RS resource of the identified RS resource identification information or the cell identification information of the candidate cell or the adjacent cell. The command or second command is a Layer 1 or Layer 2 ("L1 / L2") signaling, where the L1 signaling includes downlink control information ("DCI") and the L2 signaling includes media access control elements ("MAC CE"). The L3 measurement setting includes a list of measurement information, where the measurement information includes candidate cell identification information or a cell-based offset based on an L3 measurement threshold for the candidate cell. The L3 measurement setting includes a list of measurement information, which includes at least one of candidate cell identification information, a list of frequency information, or a list of information to be measured. The frequency information includes at least one of the following: frequency, or a frequency-based offset based on the L3 measurement threshold for the candidate cell.Here, the measurement target information includes at least one of measurement target identification information or a measurement target-based offset based on the L3 measurement threshold for the candidate cell. The method further includes applying the L3 measurement settings associated with the identified candidate cell based on the trigger of L1 / L2 mobility to the identified candidate cell.

[0022] In another embodiment, a wireless communication method includes transmitting a configuration message that includes a plurality of candidate cells, each having a configuration, and a measurement configuration for at least one of the candidate cells, and receiving a measurement report for the at least one candidate cell based on the measurement configuration. The method further includes transmitting a command that identifies at least one of the candidate cells based on the measurement report, wherein the command is configured to trigger Layer 1 or Layer 2 ("L1 / L2") mobility from the current serving cell to the identified candidate cell, based on the command and the configuration of the identified candidate cell. The configuration message and the command are transmitted from the base station to the user equipment ("UE"), and the base station receives the measurement report from the UE. The measurement configuration includes at least one Layer 1 ("L1") measurement configuration or Layer 3 ("L3") measurement configuration for at least one of the candidate cells or an adjacent cell. The method further includes RS resource identification information and at least one of a synchronization signal block (SSB) resource, a channel state information reference signal (CSI-RS) resource, or a temporary reference signal (TRS) resource. RS resources for a candidate cell or adjacent cell are configured within a set of RS resources for the current serving cell, or via a separate structure for listing RS resources for a candidate cell or adjacent cell. The L1 measurement setting includes a threshold for the L1 reference signal received power (RSRP) measurement of the serving cell to control L1 measurements for the candidate cell or adjacent cell. The L1 measurement setting includes a reporting setting to trigger measurement reporting based on L1 measurements for the candidate cell or adjacent cell. The reporting setting includes reporting setting identification information and an identification reporting type.

[0023] The measurement report type includes the type of report triggered based on a measurement report event. The measurement report event includes the L1 measurement of an adjacent cell being better than a threshold, the L1 measurement of the adjacent cell being better than the L1 measurement of the serving cell with an offset, the L1 measurement of the serving cell being worse than a first threshold and the L1 measurement of the adjacent cell being better than a second threshold, or the L1 measurement of the serving cell being worse than the first threshold and the L3 measurement of the adjacent cell being better than the second threshold. The method further includes sending a second command that identifies at least one of the at least one RS resource identifier, or the at least one cell identifier of the candidate cell or the adjacent cell. The method further includes receiving the measurement based on the identified RS resource of the identified RS resource identifier, or the identified cell identifier of the candidate cell or the adjacent cell. A command or a second command is a Layer 1 or Layer 2 ("L1 / L2") signaling, where the L1 signaling includes downlink control information ("DCI") and the L2 signaling includes media access control elements ("MAC CE"). The L3 measurement setting includes a list of measurement information, where the measurement information includes candidate cell identification information or a cell-based offset based on the L3 measurement threshold for the candidate cell. The L3 measurement setting includes a list of measurement information, which includes at least one of candidate cell identification information, a list of frequency information, or a list of measurement target information. The frequency information includes at least one of frequency or a frequency-based offset based on the L3 measurement threshold for the candidate cell. Where the measurement target information includes at least one of measurement target identification information or a measurement target-based offset based on the L3 measurement threshold for the candidate cell.

[0024] In one embodiment, the wireless communication device comprises a processor and a memory, the processor being configured to read code from the memory and implement any of the embodiments described above.

[0025] In one embodiment, a computer program product includes a computer-readable program medium storing code, and when the code is executed by a processor, the processor implements any of the above-described embodiments.

[0026] In some embodiments, there is a wireless communication device including a processor and a memory, and the processor is configured to read code from the memory and implement any of the methods described in any of the embodiments. In some embodiments, a computer program product includes a computer-readable program medium storing code, and when the code is executed by a processor, the processor implements any of the methods described in any of these embodiments. The above and other aspects and their implementations are described in more detail in the drawings, the specification, and the claims.

Brief Description of the Drawings

[0027] [Figure 1] It is a diagram showing an exemplary base station. [Figure 2] It is a diagram showing an exemplary random access (RA) messaging environment. [Figure 3] It is a diagram showing a network architecture of a base station central unit (CU) and a base station distributed unit (DU). [Figure 4] It is a diagram showing an embodiment of in-DU mobility of a user equipment (UE). [Figure 5] It is a diagram showing embodiments of in-DU and inter-DU mobility of a user equipment (UE). [Figure 6] It is a diagram showing an embodiment of inter-CU mobility of a user equipment (UE). [Figure 7] It is a diagram showing an embodiment of inter-cell mobility triggered by a network. [Figure 8] It is a diagram showing an embodiment of inter-cell mobility triggered by a user equipment (UE). [Figure 9]This figure shows an embodiment of in-DU mobility based on candidate cell preparation initiated by CU. [Figure 10] This figure shows an embodiment of in-DU mobility based on candidate cell preparation initiated by DU. [Figure 11] This figure shows an embodiment of inter-DU mobility based on candidate cell preparation initiated by CU. [Figure 12] This figure shows an embodiment of inter-DU mobility based on candidate cell preparation initiated by DU. [Figure 13] This figure shows an embodiment of in-DU mobility based on decisions triggered by CU. [Figure 14] This figure shows an embodiment of in-DU mobility based on decisions triggered by DU. [Figure 15] This figure shows an embodiment of in-DU mobility based on decisions triggered by UE. [Figure 16] This figure shows an embodiment of inter-DU mobility based on decisions triggered by CUs. [Figure 17] This figure shows an embodiment of inter-DU mobility based on decisions triggered by DUs. [Figure 18] This figure shows an embodiment of inter-DU mobility based on decisions triggered by UE. [Modes for carrying out the invention]

[0028] The Disclosure will be described in detail below with reference to the accompanying drawings, which constitute part of the Disclosure and illustrate specific examples of embodiments. It should be understood that the Disclosure may be embodied in various different forms, and therefore the cover or claimed subject matter is not limited to any of the embodiments described below.

[0029] Throughout the specification and claims, terms may have nuances implied or suggested in context beyond their expressly stated meanings. Similarly, the phrases “in one embodiment” or “in several embodiments” as used herein do not necessarily refer to the same embodiment, and “in another embodiment” or “in other embodiments” as used herein do not necessarily refer to different embodiments. The phrases “in one implementation” or “in several implementations” as used herein do not necessarily refer to the same implementation, and the phrases “in another implementation” or “in other implementations” as used herein do not necessarily refer to different implementations. For example, the claimed subject matter is intended to include all or some combinations of exemplary embodiments or implementations.

[0030] Generally, terms can be understood, at least in part, from their use in context. For example, the terms “and,” “or,” or “and / or” as used herein may have various meanings, at least in part, depending on the context in which such terms are used. When typically used to associate a list such as A, B, or C, “or” may mean A, B, and C (used herein in an inclusive sense), or it may mean A, B, or C (used herein in an exclusive sense). Similarly, the terms “one or more” or “at least one,” as used herein, may, at least in part, depend on the context, be used in a singular sense to describe any feature, structure, or characteristic, or in a plural sense to describe a combination of features, structures, or characteristics. Likewise, the terms “one,” “one,” or “the” may also be understood, at least in part, depend on the context, to convey a singular usage or a plural usage. Furthermore, the terms “based on” or “determined by” may be understood not necessarily to convey an exclusive set of factors, and instead may, likewise at least in part, be allowed for the presence of additional factors that are not necessarily explicitly stated, depending on the context.

[0031] Radio Resource Control ("RRC") is a protocol layer between the UE and the base station at the IP level (network layer). There can be various Radio Resource Control states, such as RRC_CONNECTED, RRC_INACTIVE, and RRC_IDLE. RRC messages are transmitted via the Packet Data Convergence Protocol ("PDCP"). As described, the UE can transmit data via the Random Access Channel ("RACH") protocol or the Configured Grant ("CG") protocol. Using CG can reduce waste of periodically allocated resources by allowing multiple devices to share periodic resources. A base station or node may allocate CG resources to eliminate packet transmission delays and increase the utilization of allocated periodic radio resources. The CG scheme is just one example of a protocol scheme for communication; other examples, including but not limited to RACH, are possible. The wireless communications described herein may be conducted via wireless access.

[0032] As will be explained below with respect to Figures 1 to 6, a network provider may include multiple network nodes (i.e., base stations) to provide network access to user equipment ("UE" devices). Network nodes are referred to as base stations in some embodiments. Figures 4 to 6 illustrate cell mobility, where UE devices move between cells. Control signaling may be used to facilitate this mobility. Control signaling supports the transmission of downlink and uplink transmission channels and may be referred to as Layer 1 and / or Layer 2 ("L1 / L2") signaling, indicating that the corresponding information originates partly from the physical layer (Layer 1) and partly from Media Access Control (MAC) (Layer 2). Specifically, Layer 1 may include the physical layer, and Layer 2 may include MAC, RLC, and PDCP. L1 / L2 mobility based on L1 / L2 signaling can have lower latency, lower overhead, and reduced downtime.

[0033] A master node ("MN") and one or more secondary nodes ("SN") may exist. The MN may contain a master cell group ("MCG"), and each SN may contain a secondary cell group ("SCG"). The MCG is a group of cells provided by the master node ("MN"), and the SCG is a group of cells provided by the secondary nodes ("SN"). The MCG may contain a primary cell ("PCell") and one or more secondary cells ("SCell"). The SCG may contain a primary secondary cell ("PSCell") and one or more secondary cells ("SCell"). Each primary cell may be connected to multiple secondary cells. The primary cells (PCell, PSCell) are the master cells of their respective groups (MCG, SCG, respectively) and may initiate initial access. The primary cells may be used for signaling and may be referred to as special cells ("spCell"), where spCell = PCell + PSCell. The inter-cell mobility described in these embodiments may be based on PCell, PSCell, and / or SCell.

[0034] User equipment ("UE") devices may move between nodes or cells. In this case, handover or modification / addition operations may occur to improve network reliability for the UE during the move. Based on a number of potential target cells referred to as candidates, the move may be from a source cell to a target cell. Moves between cells may also involve a number of target cells that are potential candidate cells. Conditional handovers ("CHO") and conditional PSCell additions / modifications ("CPAC") are described below. CPAC may include conditional PSCell changes ("CPC") and / or conditional PSCell additions ("CPA").

[0035] Conditional handovers ("CHO") can reduce handover downtime and improve mobility reliability. A CHO is a handover executed by the UE when one or more execution conditions are met. The UE can evaluate the execution conditions when it receives the CHO configuration and stop evaluating the conditions when the handover is triggered. The CHO configuration may include candidate PCell configurations generated by candidate target nodes and corresponding execution conditions for those candidate cells.

[0036] Conditional PSCell addition / change ("CPAC") may include a UE with network configuration to initiate access to a candidate PSCell in order to consider whether the PSCell is suitable for an SN change, including an SN addition or SN change. This consideration may be based on configured conditions. UEs in a wireless network can operate under dual connectivity ("DC"), including E-UTRA intra-DC or multi-radio DC ("MR-DC"). In the E-UTRA intra-DC example, both the MN and SN provide E-UTRA access. In the MR-DC example, one node may provide New Radio ("NR") access, and the other node may provide E-UTRA or NR access.

[0037] Figure 1 shows an exemplary base station 102. The base station is also referred to as a radio network node and may be a network node (e.g., a master node ("MN"), a secondary node ("SN"), and a source / target node) as shown in Figures 3A to 7B. Base station 102 may be further identified as node B (NB, e.g., eNB or gNB) in the background of mobile communications. The exemplary base station may include a radio Tx / Rx circuit 113 that transmits and receives with user equipment (UE) 104. The base station may include a network interface circuit 116, e.g., optical or wired interconnect, Ethernet®, and / or other data transmission medium / protocol, to connect the base station to the core network 110.

[0038] The base station may also include a system circuit 122. The system circuit 122 may include a processor 124 and / or memory 126. Memory 126 may include an operation 128 and control parameters 130. Operation 128 may include instructions to be executed on one or more of the processors 124 to support the functions of the base station. For example, the operation may handle random access transmission requests from multiple UEs. Control parameters 130 may include parameters that support the execution of operation 128. For example, the control parameters may include network protocol settings, random access messaging format rules, bandwidth parameters, radio frequency mapping allocations and / or other parameters.

[0039] Figure 2 shows an exemplary random access messaging environment 200. In the random access messaging environment, UE 104 may communicate with base station 102 over random access channel 252. In this example, UE 104 supports one or more subscriber identity modules (SIMs), e.g., SIM1 202. Electrical and physical interfaces 206 connect SIM1 202 to the rest of the user equipment hardware, for example, via a system bus 210.

[0040] The mobile device 200 includes a communication interface 212, system logic 214, and a user interface 218. The system logic 214 may include any combination of hardware, software, firmware, or other logic. The system logic 214 may be implemented, for example, using one or more systems on a chip (SoC), application-specific integrated circuits (ASIC), discrete analog and digital circuits, and other circuits. The system logic 214 is part of the implementation of any desired function within the UE 104. In this regard, the system logic 214 may include logic to facilitate, for example, decoding and playback of music and video such as MP3, MP4, MPEG, AVI, FLAC, AC3 or WAV, execution of applications, receiving user input, saving and retrieving application data, establishing, maintaining and terminating cellular telephone calls or data connections such as Internet connections, establishing, maintaining and terminating wireless network connections, Bluetooth® connections, or other connections, and displaying relevant information on the user interface 218. The user interface 218 and input 228 may include a graphical user interface, a touch sensor display, haptic feedback or other haptic output, voice or facial recognition input, buttons, switches, speakers, and other user interface elements. Additional examples of input 228 include microphones, video and still camera, temperature sensors, vibration sensors, rotation and orientation sensors, headset and microphone input / output jacks, Universal Serial Bus (USB) connectors, memory card slots, radiation sensors (e.g., IR sensors), and other types of inputs.

[0041] The system logic 214 may include one or more processors 216 and memory 220. Memory 220 stores, for example, control instructions 222 for the processor 216 to execute in order to perform a desired function for the UE 104. Control parameters 224 provide and define setting and operation options for the control instructions 222. Memory 220 may store BT, WiFi, 3G, 4G, 5G, or other data 226 transmitted by the UE 104 via the communication interface 212 or already received. In various implementations, system power may be supplied by a power storage device, such as a battery 282.

[0042] In the communication interface 212, the radio frequency (RF) transmit (Tx) and receive (Rx) circuit 230 handles the transmission and reception of signals via one or more antennas 232. The communication interface 212 may include one or more transceivers. The transceivers may be wireless transceivers including modulation / demodulation circuits, digital-to-analog converters (DACs), shaping tables, analog-to-digital converters (ADCs), filters, waveform shapers, filters, preamplifiers, power amplifiers, and / or other logic for transmitting and receiving via one or more antennas or (in some devices) via a physical (e.g., wired) medium (in some devices).

[0043] The transmitted and received signals may conform to any of the diverse formats, protocols, modulation (e.g., QPSK, 16-QAM, 64-QAM, or 256-QAM), frequency channels, bit rates, and coding configurations. For example, the communication interface 212 may include transceivers that support transmission and reception under 2G, 3G, BT, WiFi, Universal Mobile Telecommunications System (UMTS), High-Speed ​​Packet Access (HSPA)+, and 4G / Long-Term Evolution (LTE) standards. However, the technologies described below are also applicable to other wireless communication technologies, whether or not they originated from the 3rd Generation Partnership Project (3GPP®), the GSM® Association, 3GPP2, IEEE, or other partnerships or standardization bodies.

[0044] Multiple RAN nodes (e.g., eNB, gNB) of the same or different radio access technology ("RAT") can be deployed on the same or different frequency carriers within a given geographical area, and they can interact via dual connectivity operations to provide a shared communication service to the same target UE. A multi-RAT dual connectivity ("MR-DC") architecture may have a non-pseudo-collocation master node ("MN") and secondary nodes ("SN"). The Access Mobility Function ("AMF") and Session Management Function ("SMF") may be control plane entities, while the User Plane Function ("UPF") is a user plane entity within New Radio ("NR") or 5GC. The signaling connection between the AMF / SMF and the master node ("MN") may be a Next Generation-Control Plane ("NG-C") / MN interface. The signaling connection between the MN and the SN may be an Xn-Control Plane ("Xn-C") interface. The signaling connection between the MN and the UE is a Uu-Control Plane ("Uu-C") RRC interface. All of these connections manage the configuration and operation of the MR-DC. The user plane connection between the User Plane Function ("UPF") and the MN may be an NG-U(MN) interface instance.

[0045] Figure 3 shows a network architecture of base station centralized units (CUs) and base station distributed units (DUs). Figure 3 shows base stations ("gNBs") communicating with the overall network ("5GC"). Base stations can communicate with each other via a control plane interface ("Xn-C"). One base station is shown having one CU connected to two DUs via an F1 interface. This is just one example of a base station arrangement. In some embodiments, there may be one or any number of DUs connected to a single CU.

[0046] A base station can be divided into two physical entities named a centralized unit ("CU") and a distributed unit ("DU"). Generally, the CU may provide support for the upper layers of the protocol stack, such as SDAP, PDCP, and RRC, while the DU may provide support for the lower layers of the protocol stack, such as RLC, MAC, and the physical layer. The CU may include operations for user data transmission, mobility control, radio access network sharing, and session management, in addition to functions specifically assigned to the DU. The DU is a logical node with a subset of base station functions and may be controlled by the CU.

[0047] A CU may be a logical node that controls the operation of one or more DUs and hosts the base station's RRC, SDAP, and PDCP protocols, or the base station's RRC and PDCP protocols. A DU may be a logical node that hosts the base station's RLC, MAC, and PHY layers, and its operation may be controlled at least partially by a CU. A single DU may support one or more cells. However, each cell is supported by only one DU. Each base station may support a large number of cells. As described in the embodiments herein, cell mobility between cells may originate from different CUs or DUs, or may be within a CU and / or DU.

[0048] L1 / L2 Mobility

[0049] The inter-cell mobility based on L1 / L2 described herein may occur in several different examples. For L1 / L2 mobility, there may be intra-DU mobility in which a UE changes cells within a single DU. Examples of intra-DU mobility include 1) PCell changes within one DU (which may include PCell changes with SCell changes), 2) PSCell changes within one DU (which may also include PSCell changes with SCell changes), and 3) PCell changes within one DU with PSCell changes within one DU (which may include SCell changes within one cell group). In another L1 / L2 mobility embodiment, there may be intra-CU and inter-DU mobility in which a UE changes cells between different DUs, but within a single CU. Examples of intra-CU and inter-DU mobility include 1) PCell changes within one CU but across DUs (which may include PCell changes with SCell changes), and 2) PSCell changes within one CU but across DUs (which may include PSCell changes with SCell changes). In another L1 / L2 mobility embodiment, there may be inter-CU mobility in which the UE changes cells between different CUs. Examples of inter-CU mobility include 1) PCell changes across CUs (which may include PCell changes accompanied by SCell changes), and 2) PSCell changes across CUs (which may include PSCell changes accompanied by SCell changes). In another embodiment, there may be SCell changes / additions, and this example may include SCell additions / modifications within a single cell group. Figures 4 to 6 illustrate embodiments of inter-cell UE mobility.

[0050] Figure 4 shows an embodiment of intra-DU mobility of user equipment (UE). The base station may include a CU and at least one DU. In this embodiment, a single DU having multiple cells is shown. Both cell 1 and cell 2 originate from the single DU. In this example, UE 402 is able to move from cell 1 to cell 2, and the UE trajectory from cell 1 to cell 2 is shown in Figure 4. Mobility from a cell may occur when UE 402 is located between two cells and moving toward a third location within cell 2. This is intra-DU mobility because the UE is moving between cells within a single DU.

[0051] Figure 5 illustrates embodiments of intra-DU and inter-DU mobility of user equipment (UE). In this embodiment, the base station may include a CU and two DUs (DU_1 and DU_2). Each DU may have multiple cells, but in this example, each DU is shown to provide one cell, with DU_1 providing cell 1 and DU_2 providing cell 2. In this example, UE 502 is able to move from cell 1 to cell 2, and the UE trajectory from cell 1 to cell 2 is shown in Figure 5, which also causes a transition from DU_1 to DU_2. Mobility from a cell may occur when UE 402 is located between two cells and is moving toward a third location within cell 2. This is intra-CU mobility because the UE is moving within a single CU. However, this is also inter-DU mobility because the UE is moving between different DUs.

[0052] Figure 6 shows an embodiment of inter-CU mobility of user equipment (UE). In this embodiment, the base station may include multiple CUs (CU_1 and CU_2). Each CU may include multiple DUs, but in this example, each CU is shown to have one corresponding DU (CU_1 has DU_1, CU_2 has DU_2). Each DU is shown to have multiple cells. In this example, the UE trajectory of UE 602 passes through Cell_2 to Cell_3, inter-CU position 604 (between CU_1 and CU_2), CU_5, and Cell_6. When the UE moves, mobility may change cells as shown, or may transition between multiple cells. Since UE 602 switches cells from CU_1 to CU_2 (at inter-CU position 604), this transition is referred to as inter-CU mobility.

[0053] Network-triggered L1 / L2 mobility

[0054] Inter-cell mobility can be triggered by the network (e.g., base stations) or by the UE. As described, L1 / L2 signaling is used for improved inter-cell mobility. The examples described throughout may be triggered by the network or by the UE, and the embodiments shown in Figures 7-8 are applicable to other embodiments.

[0055] Figure 7 shows an embodiment of network-triggered inter-cell mobility. This embodiment shows communication or signaling between the UE, source cell, and target cell. The communication shows how the UE can move from the source cell to the target cell and the L1 / L2 signaling used as part of the transition. In block 702, the network ("NW") pre-configures one or more candidate / adjacent cells for inter-cell mobility via RRC signaling (e.g., RRCReconfiguration messages). The candidate cell configuration may include multiple candidates that will serve as the target cell. The following describes other embodiments and examples with respect to the candidate list and what the configuration includes. In block 704, the UE responds to the RRC message with an acknowledgment / completion message to the network in the source cell. In one embodiment, this message may be RRCReconfigurationComplete. In block 706, the UE reports L1 and / or L3 measurements regarding the adjacent cell (i.e., potential candidate cell) to the network. The following describes other embodiments and examples regarding measurement and adjacent / candidates.

[0056] In one embodiment, in block 708, the source cell of the network determines, based on measurements, at least one of the candidate cells to be activated. The candidate cell to be activated may be referred to as the identified cell or identified candidate cell. The identification process is described further below. Based on the identification of at least one target cell, the source cell sends a trigger command to the UE in block 710 that includes the identification information of at least one target cell. This trigger command is an L1 / L2 command. Based on the receipt of this L1 / L2 command, the UE switches to the target cell in block 712 and communicates with the target cell in block 714. Communication between the UE and the target cell is via L1 / L2 signaling. As described, using L1 / L2 signaling for cell mobility can offer several advantages. In some embodiments, configuration details of adjacent / candidate cells (including the target cell) may be provided to identify or determine the target cell. This information may be further used to establish L1 / L2 communication in block 714 after identification by the UE.

[0057] L1 / L2 mobility triggered by UE

[0058] Inter-cell mobility can be triggered by the network (e.g., base stations) or by the UE. As described, L1 / L2 signaling is used for improved inter-cell mobility. The examples described throughout may be triggered by the network or by the UE, and the embodiments shown in Figures 7-8 are applicable to other embodiments.

[0059] Figure 8 shows an embodiment of inter-cell mobility triggered by a user device (UE). This embodiment shows communication or signaling between the UE, source cell, and target cell. The communication shows how the UE can move from the source cell to the target cell and the L1 / L2 signaling used as part of the transition. In block 802, the network ("NW") pre-configures one or more candidate / adjacent cells for inter-cell mobility via RRC signaling (e.g., RRCReconfiguration messages). The candidate cell configuration may include multiple candidates that will serve as the target cell. Furthermore, the configuration message includes trigger conditions used by the UE to trigger mobility based on the configuration of the candidate cells. The following describes other embodiments and examples with respect to the candidate list, configuration, and trigger conditions. In block 804, the UE responds to the RRC message with an acknowledgment / completion message to the network in the source cell. In one embodiment, this message may be RRCReconfigurationComplete.

[0060] In the case of an example triggered by a UE, the UE evaluates the trigger condition in block 806. The evaluation of the trigger condition is used in block 808 to identify the target cell from among the candidate cells. The trigger condition may also be called the execution condition. Specifically, if at least one candidate cell satisfies the trigger condition, the UE can switch to that candidate cell. That is, the UE does not have to switch to a candidate cell if it does not satisfy the trigger condition. Identification in block 808 may also include activating the target cell or switching to the target cell, and the UE can communicate with the target cell in block 810. Communication between the UE and the target cell is via L1 / L2 signaling. As described, using L1 / L2 signaling for cell mobility can offer several advantages. In some embodiments, configuration details of adjacent / candidate cells (including the target cell) may be provided to identify or determine the target cell. This information may be further used in block 810 to establish L1 / L2 communication after identification by the UE.

[0061] Candidate cell settings

[0062] As illustrated with respect to Figures 7 and 8, the candidate cell may include a transmitted configuration. This configuration may include configuration parameters provided to identify the candidate cell (e.g., the target cell). The candidate cell configuration may include lower-layer configurations (e.g., RLC layer configuration, MAC layer configuration, and / or physical layer configuration). In some embodiments, the candidate cell configuration may include at least one information element (IE) from among CellCroupConfig, SpCellConfig, ServingCellConfigCommon, and / or ServingCellConfig.

[0063] Candidate cell settings may be provided via different options. In one embodiment, each candidate cell setting may be contained in a single RRC container and associated with cell identification (ID) information (e.g., as in a CHO / HO-based solution). In other embodiments, candidate cell settings may be included as a cell list in an RRC message, and each cell setting may be associated with cell identification information (e.g., as in a cell activation / deactivation-based solution).

[0064] Cell ID information used for configuring and maintaining candidate cells may include a candidate cell configuration index (e.g., CandReconfigId), a candidate / serving cell ID (e.g., ServCellIndex), a physical cell ID (PCI), a PCI+ frequency, or a reference signal (RS) ID associated with the candidate cell (e.g., an RS ID associated with the candidate cell via PCI, configured as part of the current serving cell configuration). The RS may be at least one of a synchronous signal block (SSB), a channel status information (CSI-RS), or a temporary / tracking reference signal (TRS). In other embodiments, a transmit configuration indicator (TCI) status ID associated with the candidate cell may be used. The TCI status may be associated with the candidate cell (e.g., via PCI) or configured as part of the current serving cell configuration.

[0065] A stored candidate cell can be activated as either a SpCell or an SCell. In some embodiments, a cell may be activated as both. Examples of cases where a cell is activated as either a SpCell, an SCell, or both are described below.

[0066] In one embodiment for identifying candidate cells, there may be separate structures / lists for candidate SpCells (i.e., PCells, PSCells) and candidate SCells, for example, a list of candidate SpCells (e.g., candidateSpCellToAddModList, candidateSpCellToReleaseList) and a list of candidate SCells (candidateSCellToAddModList, candidateSCellToReleaseList).

[0067] In another embodiment for identifying candidate cells, there may be a common structure / list for candidate cells (e.g., candidateCellToAddModList, candidateCellToReleaseList). Each entry may be set to either a candidate SpCell or a candidate SCell. In this example, there may be an indicator / flag (e.g., candidateCellType, candidateSpCell, or candidateSCell) indicating whether a cell can be a candidate SpCell or a candidate SCell. In another alternative example of this example, there may be different cell ID ranges assigned to candidate SpCells and candidate SCells (e.g., values ​​0 to X are assigned to candidate SpCells, and values ​​X+1 to N are assigned to candidate SCells). In another alternative example of this example, there may be a bitmap used to indicate which cells can be activated as SpCells (e.g., a bit in the bitmap set to 1 indicates that a cell can be activated as a SpCell). In another alternative example of this example, the candidate cell configuration may contain SpCell-specific settings (e.g., SpCellConfig, reconfigurationWithSync, PUCCH-Config) that can be used to distinguish whether the candidate cell can be activated as a SpCell or a SCell. For example, if the candidate cell configuration contains SpCell-specific commands, the candidate cell is used as a candidate SpCell; otherwise, it is used as a candidate SCell.

[0068] In another embodiment for identifying candidate cells, a common structure / list (e.g., candidateCellToAddModList, candidateCellToReleaseList) may exist for candidate cells. Each entry may be configured as a candidate cell for both SpCell and SCell. In an alternative example of this embodiment, for an entry that includes, for example, SpCell-specific settings (e.g., SpCellConfig, reconfigurationWithSync, PUCCH-Config), the associated candidate cell can be used as both a candidate SpCell and a candidate SCell. Otherwise, this entry may be used as a candidate SCell. In another alternative example of this embodiment, this entry includes two sub-entries, one sub-entry containing settings used for a candidate SpCell (e.g., including SpCell-specific settings), and the other sub-entry containing settings used for a candidate SCell (e.g., not including SpCell-specific settings). It may be up to the network ("NW") to decide how to use a candidate cell as a SpCell or SCell.

[0069] In another embodiment, an indicator or flag in the L1 / L2 command that triggers mobility may also indicate whether the cell is activated as a SpCell. SpCell-specific settings may be used / applied by the UE when the cell is activated as a SpCell.

[0070] In some embodiments, the network may also provide information about which cells can be activated simultaneously. Candidate cell mapping / combination information can be provided through several different methods. In one example, there may be a list of cell combinations (e.g., candidateCellCombinationList) that shows which candidate cells can be activated simultaneously. Each item in this list may contain a cell combination that includes a cell combination ID and / or multiple candidate cell IDs (to identify any potential cell combination). In another example, there may be a bitmap that shows which candidate cells can be activated simultaneously (e.g., the bitmap is N bits in size to show N candidate cells). A bit set to 1 in the bitmap indicates that cells can be activated simultaneously, or a bit set to 0 indicates that cells cannot be activated simultaneously.

[0071] [Table 1]

[0072] In this example, with four candidate cells pre-configured by the network, only 1+2+3, 1+3+4, and 1+2+4 are permitted to be activated simultaneously. The network can provide the above bitmap table as part of the configuration. Alternatively, the network may provide a list of candidate cell ID combinations, e.g., {Cell_1, Cell_2, Cell_3}, {Cell_1, Cell_3, Cell_4}, {Cell_1, Cell_2, Cell_4}.

[0073] There may be various embodiments for reducing the signaling overhead for candidate cell configuration. In one embodiment, one or more separate common sets / templates are defined as baselines for candidate cell configuration, and candidate cells are configured based on the baseline configuration and delta configurations added to the baseline configuration. In another embodiment, one or more serving / candidate cells are identified as reference cells (e.g., including reference IDs for the current serving cell ID or other candidate cell IDs) and configured candidate cells in the candidate cell configuration entry in the candidate cell list, based on reference cell configurations and delta configurations for reference cell configurations. In this embodiment, serving cells may be considered for reuse as candidate cells, or vice versa. Specifically, a reference cell indicator (e.g., referenceCell) may be included in the candidate cell configuration or serving cell configuration. For example, for a candidate cell entry, a serving cell ID (e.g., SCellIndex or ServCellIndex) may be included to indicate that the referenced serving cell is also considered a candidate cell for L1 / L2 mobility. To indicate that this candidate cell will be added as a serving cell (for example, via an RRC reset message), the candidate cell ID may be shown within the current serving cell configuration (e.g., SpCellConfig or SCellConfig).

[0074] L1 / L3 measurement

[0075] Figure 7 shows L1 / L3 measurements used for measurement reporting to help determine / identify target cells from candidate cells. In some embodiments, the L1 / L3 measurement settings may be provided to the UE via the network.

[0076] The NW may provide the UE with L1 measurement settings for a candidate cell or adjacent cell via at least one of the following alternatives 1) to 3): 1) Set up / add L1 measurements for the candidate cell within the current L1 measurement settings on the serving cell (e.g., channel state information measurement settings CSI-MeasConfig); 2) Set up or reuse L1 measurements for the candidate cell within the RRM measurement settings (e.g., MeasConfig); 3) Define a separate structure for providing L1 measurements for the candidate cell; or 4) Set up or include L1 measurement settings for the candidate cell within each candidate cell setting.

[0077] The L1 measurement settings may include at least one of the following: an add / modify list for L1 metered / resources, a remove list for L1 metered / resources, an add / modify list for L1 measurement IDs (where the measurement ID is a link between the metered / resource and the reporting setting), a remove list for L1 measurement IDs, an add / modify list for L1 reporting settings, a remove list for L1 reporting settings, a measurement gap setting for L1 measurements, or a threshold for SpCell / serving cell RSRP measurement control (e.g., L1 SSB RSRP threshold, or L1 CSI-RS RSRP threshold) when the UE is requested to perform L1 measurements on non-serving / candidate cells. If a serving cell has deteriorated below a threshold, the UE may be requested to perform L1 measurements on non-serving / candidate / adjacent cells. These measurements are then used to select / identify target cells from among the candidate cells.

[0078] L1 measurements may be provided or activated in different embodiments. The measurement may be referred to as a subject / resource (e.g., a reference signal resource used for the L1 measurement). It may be provided by the following alternatives 1) to 3): 1) Setting up or adding a reference signal (RS) resource related to the candidate / adjacent cell within the L1 measurement configuration for the current serving cell (e.g., CSI-ResourceConfig). 2) Reusing an RS resource related to the candidate / adjacent cell within the L3 / RRM measurement, or setting up / adding an additional RS resource related to the candidate / adjacent cell within the L3 / RRM measurement configuration (e.g., CSI-RS-ResourceConfigMobility). 3) Defining a separate structure that provides RS resources for the candidate / adjacent cell. Or 4) Setting up / including an RS resource for the candidate cell within each candidate cell configuration. The RS type may include at least one of SSB, CSI-RS, and TRS. In some embodiments, an RS resource may include at least one of the following: 1) an RS resource ID, 2) a frequency-domain resource of the RS, 3) a time-domain resource of the RS, or 4) a resource type (e.g., aperiodic, semi-persistent, or periodic). For an RS measurement resource activation to be set, the RS / measurement resource may be considered activated (e.g., detectable or measurable by the UE) when set, or deactivated (e.g., undetectable or unmeasurable by the UE) when set. The NW may explicitly indicate (e.g., via L1 / L2 commands or RRC signaling) which RS resources related to an adjacent / candidate cell should be activated (e.g., by indicating the RS resource ID, candidate cell ID). If an RS resource related to an adjacent / candidate cell is activated, the UE may be required to perform an L1 measurement on the RS resource related to the adjacent / candidate cell. If the RS resource associated with the adjacent / candidate cell is deactivated, the UE may not be required to perform an L1 measurement on the RS resource associated with the adjacent / candidate cell.

[0079] L1 measurement reporting may be configured in various ways. An L1 measurement reporting configuration (e.g., CSI-ReportConfig) may be used to configure L1 measurement reporting on the current serving cell. This may include at least one of the following: a reporting configuration ID, or reporting type (e.g., aperiodic, semi-persistent, periodic, or event-triggered). For the event-triggered type, the triggering event may be established as a new event based on the L1 measurement. For example, the L1 measurement of an adjacent cell is better than a threshold (e.g., A4 event, RSRP, RSRQ, and / or SINR value). In another example, the L1 measurement of an adjacent cell is better than the L1 measurement of the SpCell / serving cell by an offset or more (e.g., A3 event). In another example, the L1 measurement of a SpCell / serving cell falls below a first threshold, and the L1 measurement of an adjacent cell falls above a second threshold (e.g., event A5). The L1 measurement report is further configured by reusing L3-based measurement events (e.g., events A3 / A4 / A5, etc.), but can be configured to have additional parameter values ​​for L1 / L2 mobility (e.g., additional hysteresis, timeToTrigger, threshold). More flexible values ​​can make it easier to trigger L1 / L2 mobility. The L1 measurement report may further be configured based on the L1 measurement on the serving cell and the L3 measurement on the candidate / adjacent cell due to a new event. For example, the L1 measurement of a SpCell / serving cell falls below a first threshold, and the L3 measurement of an adjacent cell falls above a second threshold (e.g., an event like A5).

[0080] The L1 measurement gap can be configured to define the window in which the UE can perform inter-frequency and / or intra-frequency L1 measurements. The measurement gap may be provided by reusing the measurement gap settings for L3 / RRM measurements (e.g., MeasGapConfig). Additional parameter values ​​may be set for L1 measurements (e.g., additional gapOffset, mgl, mgrp, mgta, etc.). The offset values ​​may be based on the parameter values ​​for L3 measurements (e.g., offset values ​​for gapOffset, mgl, mgrp, mgta, etc.). The L1 measurement gap can be configured to define a separate measurement gap setting for L1 measurements (e.g., L1MeasGapConfig). The L1 measurement gap setting is: ● Gap type (for example, gap per FR1, gap per FR2, gap per UE), ● Gap offset, ● Measurement gap repetition period, ● Measurement gap length, ● Measurement gap timing advance, or ● Reference serving cells in which SFN and subframes are used for gap calculations for this gap pattern. It may include at least one of the following items.

[0081] In Figure 8, the trigger conditions are provided to the UE. The trigger conditions, also referred to as execution conditions, define the conditions or thresholds that can trigger mobility. In one embodiment, the trigger conditions include a list of measurement identifiers (measIds), which may be associated with L1 / L3 metered objects / resources and reporting settings as described above. In another embodiment, the trigger conditions include any of the measurement events listed above.

[0082] Candidate cells may be associated with trigger conditions. Specifically, one or more execution conditions may be associated with one candidate cell. In another embodiment, one or more execution conditions may be associated with multiple candidate cells (e.g., one or more conditions for candidate cell combinations that include both a SpCell and an associated SCell). When multiple conditions are associated with a candidate cell / cell combination, the UE may consider the condition to be met if all conditions are met (e.g., each condition relation is "AND") or if one of the conditions is met (e.g., each condition relation is "OR").

[0083] The configured Radio Resource Management (RRM) measurements may be affected by the execution of L1 / L2 mobility (e.g., changes between inter-frequency and intra-frequency measurements). To ensure that events remain valid after the execution of L1 / L2 mobility, trigger events on the UE side (e.g., for other candidate cells or CHOs, where coexistence with CHOs is permitted) should be considered. The updated RRM measurement settings (e.g., measurement target settings, measurement reporting settings, measurement gap settings) may be provided in different ways in various embodiments. In one embodiment, the NW pre-configures the UE with the measurement settings to be updated, associated with each candidate cell. For example, the measurement settings may be included within each candidate cell setting, or a separate structure for updating the measurement settings may be defined (e.g., a list of measurement settings, each associated with a candidate cell ID). When L1 / L2-based mobility is triggered, the UE applies the corresponding measurement settings for the target cell. In another embodiment, the UE automatically triggers a measurement setting switch when L1 / L2-based mobility is triggered or upon successful completion of mobility (for example, the measId associated with the measObjectId value corresponding to the source frequency is associated with the measObjectId value corresponding to the target frequency). In another embodiment combining the embodiments described above, the NW pre-configures the UE with some of the updated measurement settings associated with each candidate cell (e.g., gap settings, reporting settings). When L1 / L2-based mobility is triggered, the UE performs an automatic mobility switch and applies the corresponding measurement settings for the target cell based on the baseline / source measurement settings.

[0084] For reporting configuration updates (including trigger / execution conditions), source configurations can be saved as templates / baselines, or the NW provides a separate set of reporting configurations as templates / baselines. For each candidate cell, the NW provides a set of delta configurations that can be applied based on the template / baseline when triggering L1 / L2 mobility. The delta configurations may include a list of cell-based offset values ​​(e.g., RSRP, RSRQ, SINR values) each associated with each candidate cell. When a candidate cell is selected / indicated to be activated / switched as a target cell, the UE generates a new reporting configuration for the target cell by adding the cell-based offset values ​​associated with the cell to the threshold / offset values ​​in the template / baseline configuration. An exemplary signaling configuration is shown in Table 2 below.

[0085] [Table 2]

[0086] In Table 2, the measurement information for the delta setting includes a list of candidate cell IDs and their associated cell-based offset values. The delta setting may further include a set of frequency / MO-based offset values ​​(e.g., RSRP, RSRQ, SINR values) for each candidate cell. When a candidate cell is selected / indicated to be activated / switched as a target cell, the UE adds the frequency-based offset value associated with the cell to the threshold / offset value associated with the corresponding frequency in the template / baseline setting. An exemplary signaling configuration is shown in Table 3 below.

[0087] [Table 3]

[0088] In Table 3, the measurement information for the delta setting includes a list of candidate cell IDs and a list of associated measurement target / frequency information. Each measurement target / frequency information includes a list of measurement target IDs or frequencies and an associated measurement target / frequency value.

[0089] To provide measurement gap setting updates, there may be a list of measurement gap settings (e.g., measGapConfigList) associated with each of the set of candidate cells (e.g., a list of candidate cells in GapConfig). In another embodiment of providing measurement gap setting updates, there may be a list of candidate cells, each associated with one measurement gap setting or a set of measurement gap settings. In another embodiment of providing measurement gap setting updates, there may be a template / baseline measurement gap setting (e.g., a source measurement gap setting), and the list of updated measurement settings is a delta setting based on the template / baseline. When a candidate cell is activated, the UE autonomously applies / activates the associated measurement gap setting.

[0090] Network-based triggering for L1 / L2 mobility

[0091] Returning to Figure 7, L1 / L2 mobility may also be triggered by the network. In block 706, L1 / L3 measurements concerning adjacent cells (including candidate cells) are reported by the UE to the NW. In block 708, the NW selects a target candidate cell based on the measurement report and in block 710 sends a trigger command (e.g., an L1 / L2 command) instructing the UE to select the indicated cell and perform inter-cell mobility. Below, another example of triggering an L1 / L3 measurement report is described. When conditions / events for the configured report type (e.g., aperiodic, semi-persistent, periodic, or event-triggered) are met, the UE can trigger an L1 / L3 measurement report. For the aperiodic type, when a DCI trigger for an L1 measurement report request is received, the UE should send an aperiodic L1 measurement report (e.g., a CSI report) on PUSCH. For semi-persistent types, when a DCI trigger is received for an L1 measurement report request, the UE may send a semi-persistent L1 measurement report (e.g., a CSI report) on the PUCCH. For semi-persistent types, when a MAC CE is received for an L1 measurement report request, the UE should send a semi-persistent L1 measurement report (e.g., a CSI report) on the PUCCH. For periodic types, the UE should send periodic L1 measurement reports (e.g., a CSI report) on the PUCCH according to the configured / defined period. For event-triggered types, when an L1 measurement that satisfies the configured conditions / event is determined / detected, the UE should send an L1 measurement report (e.g., via a CSI report or MAC CE).

[0092] In an alternative embodiment, the UE may trigger an L1 / L3 measurement report when N consecutive L1 measurements satisfying the conditions (for example, for the type triggered by the above events) are detected. In an alternative embodiment, the UE may trigger an L1 / L3 measurement report when N consecutive "out of sync" indications are detected from a lower layer for a SpCell / serving cell (i.e., when a physical layer problem is detected). In an alternative embodiment, the UE may trigger an L1 / L3 measurement report when a radio link failure (RLF) or beam failure recovery (BFR) on a SpCell / serving cell is detected, such as T310 expiration, T312 expiration, random access problem, maximum retransmission count reached, or listening before talk (LBT) failure.

[0093] Measurement reports can be transmitted via L1 signaling (e.g., via CSI reporting) or MAC CE. Measurement reports may include at least one of the following for adjacent / candidate cells and / or serving cells: L1 SSB RSRP, L1 SSB RSRQ, L1 SSB SINR, L1 CSI-RS RSRP, L1 CSI-RS RSRQ, L1 CSI-RS SINR. The network can also indicate, for example via L1 / L2 commands (downlink control information (DCI), MAC control elements (MAC CE)), which measurements related to adjacent / candidate cells are requested to be reported (e.g., via RS resource ID, candidate cell ID). The UE may transmit measurement reports containing only the measurement results for the indicated adjacent / candidate cells.

[0094] The trigger command may be at least one of the following: physical layer DCI, MAC CE, or RRC signaling. The trigger command may include at least one of the following pieces of information for one or more selected cells to indicate that the UE will activate or switch to the indicated cell: ● Candidate cell setting index (e.g., CandReconfigId). ● Candidate / serving cell ID (e.g., ServCellIndex). ● PCI or PCI+ frequency. ● A reference signal (RS) ID associated with the candidate cell, for example, an RS ID associated with the candidate cell (e.g., via the physical cell ID (PCI)), is already configured as part of the current serving cell configuration. The RS may be at least one of the following: a synchronization signal block (SSB), a channel status information reference signal (CSI-RS), or a tracking / transient reference signal (TRS). ● The Sending Configuration Indicator (TCI) status ID associated with the candidate cell (e.g., the TCI status associated with the candidate cell via PCI) is already set as part of the current serving cell configuration. Or, ● Candidate cell combination ID (for example, to indicate which candidate cells can be activated simultaneously).

[0095] The trigger command also, ● Timing Advance (TA) value or Compensated TA value of the selected / indicated candidate cell, ● Cell Radio Network Temporary Identifier (C-RNTI) of the selected / indicated candidate cell, ● Activate the selected / indicated candidate cell's DL / UL BWP ID, ● An instruction / flag (i.e., like DAPS HO) indicating whether the UE can maintain connectivity with the source / current SpCell / serving cell during L1 / L2-based inter-cell mobility. ● An instruction or flag indicating whether a RACH procedure is required or skipped for the selected / indicated candidate cell, or whether a RACH-less procedure is permitted. ● Initial TCI state of selected / indicated candidate cells, ● Serving cell ID for the selected / indicated candidate cell, ● PDCP overlap activation / deactivation instructions, indicating whether PDCP overlap will be activated / maintained / deactivated after completion of inter-cell mobility based on L1 / L2, or ● An indication or flag showing whether the selected / indicated candidate cell has been activated as a SpCell. It may include at least one piece of information from the following categories.

[0096] UE-based triggering for L1 / L2 mobility

[0097] Returning to Figure 8, L1 / L2 mobility may be triggered by a user device (UE). In block 806, the UE begins evaluating the execution / trigger conditions for candidate cells. If at least one candidate cell satisfies the corresponding execution conditions, the UE connects to the target candidate cell in block 808 based on the stored cell configuration. L1 / L2 mobility execution may be triggered if at least one of the following conditions is met: ● If at least one candidate cell / cell combination satisfies the corresponding execution condition, ● If at least one candidate cell / cell combination satisfies the corresponding execution condition N times in a row, ● When N consecutive "out-of-sync" instructions are detected from a lower layer for a SpCell / serving cell (i.e., when a physical layer problem is detected), ● When a radio link failure (RLF) or beam fault recovery (BFR) is detected on the SpCell / serving cell (e.g., T310 expiration, T312 expiration, random access problem, reaching the maximum RLC retransmission count, or LBT failure).

[0098] UE behavior when triggered

[0099] The above examples concern cases where the UE is triggered, but the following description of UE behavior when triggering L1 / L2-based inter-cell mobility is also applicable to both UE-triggered and NW-triggered mobility. When L1 / L2-based inter-cell mobility is triggered (for example, upon receiving an L1 / L2 trigger command or when it is detected that the execution conditions are met), the UE may perform at least one of the following operations: ● Applies / activates the stored cell settings for the indicated / selected candidate / target cell. ● If a cell is instructed by the network to be activated as a SpCell (for example, via a trigger command), the stored SpCell settings (i.e., settings including SpCell-specific settings) of the instructed / selected candidate / target cell are applied / activated. ● If instructed by NW (for example, via instructions in a trigger command), apply a new TA value or a compensated TA value based on the current TA value to the instructed / selected candidate / target cell. ● If instructed by the NW (for example, via instructions in a trigger command), apply the C-RNTI and / or serving cell ID for the instructed / selected candidate / target cell. ● When instructed by the network (for example, via instructions in a trigger command), switch to / activate the uplink (UP) / downlink (DL) / bandwidth part (BWP) according to the activated DL / UL BWP identifier (ID). ● Activate timers for L1 / L2 mobility (e.g., MAC layer timers or RRC layer timers such as T304). ● Separate from the source / current SpCell / serving cell and synchronize and connect to the designated / selected candidate / target cell. Or, ● When instructed by the network (for example, via instructions in a trigger command), maintain connection with the source / current SpCell / serving cell and synchronize and connect to the instructed / selected candidate / target cell.

[0100] Regarding connection to the target cell, the UE may perform the following processes: In one embodiment, if RACH-less is not set / allowed, the UE completes the L1 / L2-based inter-cell mobility procedure by accessing the target cell via a RACH procedure (e.g., CBRA, CFRA, 2-step RA) and sending L1 / L2 signaling to the target cell. In an alternative embodiment, if RACH-less is set / allowed (e.g., via an instruction in a trigger command), the UE sends L1 / L2 signaling to the target cell via a pre-assigned uplink authorization. In another embodiment, the UE monitors the target cell's physical downlink control channel (PDCCH) to receive an uplink authorization and sends L1 / L2 signaling to the target cell via the received uplink authorization. In yet another embodiment, the UE sends a Scheduling Request (SR) to the target cell, initiates monitoring of the target cell's PDCCH to receive an uplink authorization, and sends L1 / L2 signaling to the target cell via the received uplink authorization. In another embodiment, the UE monitors the target cell's PDCCH using the TCI state indicated in the received L1 / L2 trigger command to receive uplink permission, and the UE transmits L1 / L2 signaling to the target cell via the received uplink permission. In yet another embodiment, the UE sends an SR to the target cell, initiates monitoring of the target cell's PDCCH where the TCI state is indicated in the received L1 / L2 trigger command to receive uplink permission, and transmits L1 / L2 signaling to the target cell via the received uplink permission.

[0101] L1 / L2 signaling may include at least one of the following: physical layer uplink control information (UCI), ACK, or MAC CE. L1 / L2 signaling may also include an activation / selected candidate / target cell ID or an activation / selected candidate cell combination ID for the network.

[0102] To switch from the current / source serving cell to the target cell, a switch is performed between the candidate cell ID and the serving cell ID. When inter-cell mobility based on L1 / L2 is triggered, the UE can automatically switch between the candidate cell ID (used for setting up and maintaining the candidate cell) and the serving cell ID (used for subsequent cell operations, e.g., in the SCell activation / deactivation MAC CE) if the serving cell ID is not explicitly provided by the NW (e.g., not pre-configured using candidate cell settings and / or not indicated in the trigger command). For each candidate cell, if the candidate cell is activated as a PCell, the UE sets the serving cell ID for that cell to 0 (i.e., ServCellIndex=0), but if the candidate cell is activated as a SCell or PSCell, the UE uses the candidate cell ID previously assigned to the candidate cell (e.g., the candidate cell ID included in the RRC message with the candidate cell settings) as the serving cell ID (ServCellIndex=candidate cell ID).

[0103] Detection and handling of L1 / L2 mobility failures

[0104] The new timer may be used for L1 / L2-based inter-cell mobility (e.g., a timer like T304). The timer may be an RRC layer timer or a MAC layer timer. In one embodiment, the timer starts when L1 / L2-based inter-cell mobility is triggered (e.g., upon reception of an L1 / L2 command, or when L1 / L2 mobility triggered by the UE is executed (i.e., when a stored candidate cell configuration is applied, or when it is detected that the execution conditions have been met)). The timer is, ● Upon successful completion of L1 / L2-based inter-cell mobility, for example, upon successful completion of random access on a corresponding candidate cell, or when sending L1 / L2 instructions (e.g., UCI, ACK, MAC CE) to a corresponding candidate / target cell, ● When RLF / BFR is detected on the current / source serving cell, ● When releasing the candidate cell settings, ● When the timer is set as a MAC layer timer, the RRC layer notifies the MAC layer to stop the timer, ● If the timer is an RRC layer timer, when the MAC layer notifies the RRC layer of the successful completion of L1 / L2-based inter-cell mobility, The system stops if at least one of the following conditions is met.

[0105] If the timer is a MAC layer timer and the timer expires, the UE can trigger / send a MAC CE to report an L1 / L2 mobility failure. In another embodiment, if the timer is a MAC layer timer and the timer expires, the UE can notify a higher layer (e.g., the RRC layer) of the detection of an L1 / L2 mobility failure. The RRC layer may then trigger an RRC re-establishment procedure to report the L1 / L2 mobility failure to the NW, or it may select another candidate cell from the stored candidate cells and perform a second L1 / L2 inter-cell mobility (e.g., activate another candidate cell or switch to another candidate cell).

[0106] If the timer is an RRC layer timer and the timer expires, the UE can trigger an RRC re-establishment procedure. In another embodiment, if the timer is an RRC layer timer and the timer expires, the UE can report an L1 / L2 mobility failure to the NW. In another embodiment, if the timer is an RRC layer timer and the timer expires, the UE can select another candidate cell from the stored candidate cells and perform a second L1 / L2 inter-cell mobility (e.g., activate another candidate cell or switch to another candidate cell).

[0107] The L1 / L2 mobility failure reports described above can be sent to the network via L1 / L2 signaling (e.g., UCI, MAC CE), via RRC signaling (e.g., reusing existing RRC messages including FailureInformation, MCGFailureInformation, or SCGFailureInformation messages), or by defining new RRC messages. The failure report may include the failure type (e.g., L1 / L2 mobility failure) and / or failure candidate cell ID or failure candidate cell combination ID information.

[0108] In one embodiment, a CHO-based recovery solution may exist. If the UE fails to access a candidate cell and detects that at least one of the other candidate cells satisfies the corresponding trigger condition or a separate condition / threshold set by the NW (e.g., a condition / threshold used only for cell selection during failure recovery), the UE can automatically trigger a second L1 / L2 mobility to the selected candidate cell. If the failed cell is a candidate PCell (e.g., like DAPS) and the source cell connection is maintained during L1 / L2 mobility, the UE can fall back to the source cell and report the L1 / L2 mobility failure to the source cell. If the failed cell is a candidate PSCell or candidate SCell, the UE reports the failure information to the NW via RRC signaling (e.g., FailureInformation message or SCGFailureInformation message) or MAC CE (e.g., New Failure Report MAC CE).

[0109] If Packet Data Convergence Protocol (PDCP) duplication is configured for a UE, several alternatives may be considered for handling PDCP duplication when triggering or completing L1 / L2-based inter-cell mobility. In one embodiment, the UE voluntarily deactivates PDCP duplication when triggering L1 / L2 mobility. In another embodiment, the NW explicitly indicates whether to activate / deactivate / maintain PDCP duplication (e.g., via an L1 / L2 mobility trigger command). In yet another embodiment, if the previous logical channel (LCH) is removed during L1 / L2 mobility execution / completion (e.g., if there are no serving cells associated with the previous LCH), the UE voluntarily switches primaryPath to refer to another LCH (e.g., an LCH associated with the activated candidate cell).

[0110] CU / DU cooperation

[0111] As described above with respect to Figure 3, a network (NW) or base station may include centralized units (CUs) and distributed units (DUs). Generally, a CU may provide support for the upper layers of the protocol stack, such as SDAP, PDCP, and RRC, while a DU may provide support for the lower layers of the protocol stack, such as RLC, MAC, and the physical layer. A CU may include operations for user data transmission, mobility control, radio access network sharing, and session management, in addition to functions specifically assigned to the DU. A single DU may support one or more cells; however, each cell is supported by only one DU. Cell mobility between cells may be from different CUs or DUs, or it may be limited to within a CU and / or DU.

[0112] Several examples exist, as shown in Figures 4 to 6. Figure 4 shows an embodiment of mobility within a DU. Figure 5 shows an embodiment of mobility within a CU and between DUs. Figure 6 shows an embodiment of mobility between CUs. In these examples, mobility may be triggered by the network, as shown in Figure 7, or by user equipment (UE), as shown in Figure 8. Network-triggered mobility from Figure 7 may be further modified depending on whether it is mobility triggered by a DU or mobility triggered by a CU.

[0113] Specifically, the CU and DU coordinate to add / modify / release candidate cell settings and trigger events. There are at least four embodiments for coordination regarding the initiation / preparation of candidate cell settings. In Embodiment 1, the CU determines the proposed candidate cells and the CU determines the trigger events. In Embodiment 2, the CU determines the proposed candidate cells and the DU determines the trigger events. In Embodiment 3, the DU determines the proposed candidate cells and the DU determines the trigger events. In Embodiment 4, the DU determines the proposed candidate cells and the CU determines the trigger events.

[0114] [Table 4]

[0115] In Embodiments 1 and 2, where the CU determines the proposed candidate cells, the CU sends the proposed candidate cell list to the DU via an F1 message (e.g., a UE CONTEXT MODIFICATION REQUEST message or other message) to request the DU to configure or set it up. This message may also include instructions indicating that the procedure is for L1 / L2 mobility, and / or instructions indicating what type of L1 / L2 mobility the procedure is for (e.g., "UE triggered L1 / L2 mobility", "NW triggered L1 / L2 mobility", "CU triggered L1 / L2 mobility", or "DU triggered L1 / L2 mobility"). In Embodiment 1, the CU may also send a trigger event to the DU (e.g., for DU-triggered mobility).

[0116] In Embodiments 1 and 2, where the CU determines the proposed candidate cells, the DU sends the CU a list of accepted or rejected candidate cells, and / or candidate cell settings for each accepted candidate cell, via an F1 message (e.g., a UE CONTEXT MODIFICATION RESPONSE message or other message). If the DU accepts all proposed candidate cells, no list of accepted or rejected candidate cells is provided. If the DU fails to configure or set up some candidate cells, a list of rejected candidate cells (including the failed candidate cells) or a list of accepted candidate cells (including the accepted candidate cells) is provided. The candidate cell settings may be encapsulated within an RRC container (e.g., a HandoverPreparationInformation, CG-Config, or CG-ConfigInfo message). In Embodiment 2, the DU may also send trigger events to the CU (e.g., for mobility triggered by the UE or mobility triggered by the CU).

[0117] In embodiments 3 and 4 in which the DU determines the proposed candidate cells, the DU sends the requested candidate cell list to the CU via an F1 message (e.g., a UE CONTEXT MODIFICATION REQUIRED message or other message) to request the CU to allow the DU to configure. This message may also include instructions indicating that the procedure is for L1 / L2 mobility, and / or instructions indicating what type of L1 / L2 mobility the procedure is for (e.g., "UE triggered L1 / L2 mobility", "NW triggered L1 / L2 mobility", "CU triggered L1 / L2 mobility", or "DU triggered L1 / L2 mobility"). The DU may also provide candidate cell settings for each requested candidate cell. Candidate cell configuration may be encapsulated within an RRC container (e.g., HandoverPreparationInformation, CG-Config, or CG-ConfigInfo messages). In Embodiment 3, the DU may also send trigger events to the CU (e.g., for mobility triggered by the UE or mobility triggered by the CU).

[0118] In embodiments 3 and 4, where the DU determines the proposed candidate cells, the CU sends a list of accepted or rejected candidate cells to the DU via an F1 message (e.g., a UE CONTEXT MODIFICATION CONFIRM message). If the CU accepts all requested candidate cells, no list of accepted or rejected candidate cells is provided. If the CU rejects some candidate cells, a list of rejected candidate cells (including rejected candidate cells) or an accepted candidate cell list (including accepted candidate cells) is provided. In embodiment 4, the CU may also send a trigger event to the DU (e.g., for mobility triggered by the DU).

[0119] Trigger events may include L1 measurement-based events. For example, when the L1 measurement of an adjacent cell improves above a threshold (e.g., RSRP, RSRQ, and / or SINR values ​​for an event like A4). In another example, when the L1 measurement of an adjacent cell improves above the L1 measurement of the SpCell / serving cell by an offset or more (e.g., an event like A3). In yet another example, when the L1 measurement of the SpCell / serving cell worsens below a first threshold and the L1 measurement of an adjacent cell improves above a second threshold (e.g., an event like A5). Alternatively, for example, when the L1 measurement of the SpCell / serving cell worsens below a first threshold and the L3 measurement of an adjacent cell improves above a second threshold (e.g., an event like A5), the trigger event may include events based on the L1 measurement on the serving cell and the L3 measurement on the candidate / adjacent cell. In an alternative, the trigger event may include a list of measIds associated with L1 / L3 metered targets / resources and reporting settings.

[0120] In embodiments where information (e.g., trigger events, instructions about L1 / L2 mobility) is provided, the information may remain within the F1 message (e.g., UE CONTEXT MODIFICATION REQUEST / RESPONSE, UE CONTEXT MODIFICATION REQUIRED / CONFIRM message) and be directly forwarded to the CU or DU. In another embodiment, the information (e.g., trigger events, instructions about L1 / L2 mobility) may be provided within an RRC message (e.g., HandoverPreparationInformation, CG-Config, or CG-ConfigInfo message). This RRC message may be included as an information element (IE) within the F1 message.

[0121] Figure 9 shows an embodiment of intra-DU mobility based on candidate cell preparation initiated by the CU. Figure 9 is applicable to Embodiments 1 and 2 from Table 4. User equipment (UE) communicates with base station distributed units (DUs) and base station centralized units (CUs). Figure 4 shows intra-DU mobility, and Figure 9 shows intra-DU mobility based on candidate cell preparation initiated by the CU. In block 902, the CU determines proposed candidate cells (e.g., according to RRM measurements). The CU sends a list of proposed candidate cells to the DU via an F1 message (e.g., a UE CONTEXT MODIFICATION REQUEST message or other message) to request the DU to configure or set up the candidate cells. This message may also include instructions indicating that the procedure is for L1 / L2 mobility, and / or instructions indicating what type of L1 / L2 mobility the procedure is for.

[0122] In block 904, the DU decides whether to configure or set up the proposed candidate cells and sends the generated candidate cell configuration (e.g., CellGroupConfig) to the CU (e.g., via the UE CONTEXT MODIFICATION RESPONSE message). If the DU fails to configure or set up some candidate cells, the DU may also include in the message a list of accepted cells (e.g., a list of cells that have already been successfully configured) or a list of failed / rejected cells (e.g., a list of cells that failed to be configured). The DU may also include in the message any generated trigger events / execution conditions (e.g., for mobility triggered by the UE or CU).

[0123] In block 906, the CU sends the generated RRCReconfiguration message to the DU (e.g., via a DL RRC MESSAGE TRANSFER message). The RRC message includes candidate cell configuration and may also include trigger events / conditions associated with the candidate cell (e.g., mobility triggered by the UE). In block 908, the DU forwards the received RRCReconfiguration message to the UE. In block 910, the UE responds to the DU with an RRCReconfigurationComplete message, which the DU then forwards to the CU in block 912 (e.g., via a UL RRC MESSAGE TRANSFER message). In some embodiments, in block 906, the CU sends the generated trigger events to the DU. In alternative embodiments, blocks 906 and 912 may include UE CONTEXT MODIFICATION REQUEST and UE CONTEXT MODIFICATION RESPONSE messages.

[0124] Figure 10 shows an embodiment of in-DU mobility based on candidate cell preparation initiated by the DU. Figure 10 is applicable to embodiments 3 and 4 from Table 4. Figure 4 shows in-DU mobility, and Figure 10 shows in-DU mobility based on candidate cell preparation initiated by the DU. In block 1002, the DU determines proposed candidate cells (e.g., according to L1 measurement). The DU sends the requested candidate cell list to the CU via an F1 message (e.g., UE CONTEXT MODIFICATION REQUIRED message or other message) to request the CU to configure or set up the candidate cells. The DU may include the generated candidate cell configuration (e.g., CellGroupConfig) and / or trigger events (e.g., for mobility triggered by the CU or UE) in the message. The message may also include instructions indicating that the procedure is for L1 / L2 mobility and / or instructions indicating what type of L1 / L2 mobility the procedure is for.

[0125] In block 1004, the CU decides whether to accept the candidate cells as requested. If the CU rejects some candidate cells, it may also include in the message a list of accepted cells (e.g., a list of cell IDs already accepted) or a list of rejected / failed cells (e.g., a list of cell IDs already rejected). The CU generates an RRCReconfiguration message containing the candidate cell settings for each accepted cell, and may also include the generated trigger event / execution condition in this message (e.g., for mobility triggered by the UE), and send the RRC message to the DU via an F1 message (e.g., a UE CONTEXT MODIFICATION CONFIRM message or another message). The F1 message may also include the trigger event to the DU (e.g., for mobility triggered by the DU).

[0126] In block 1006, the DU forwards the received RRCReconfiguration message to the UE. In block 1008, the UE responds to the DU with an RRCReconfigurationComplete message, to which the DU forwards to the CU in block 1010 (e.g., via a UL RRC MESSAGE TRANSFER message). In some embodiments, the DU may generate a trigger event after the CU accepts the required candidate cells (e.g., after block 1004) and send the generated trigger event to the CU via a UE CONTEXT MODIFICATION REQUIRED message. The CU then generates an RRC reconfiguration message and sends it to the UE via the DU (e.g., sends the generated RRCReconfiguration message to the DU via a DL RRC MESSAGE TRANSFER message), and the DU forwards the received RRCReconfiguration message to the UE.

[0127] Figure 11 shows an embodiment of inter-DU mobility based on candidate cell preparation initiated by a CU. Figure 11 is applicable to Embodiments 1 and 2 from Table 4. Figure 5 shows inter-DU mobility, and Figure 11 shows inter-DU mobility based on candidate cell preparation initiated by a CU. There may be a source DU from which the UE transfers to the candidate DU (also called the target DU). In this example, the CU is not modified because this is inter-DU mobility within a CU.

[0128] In block 1102, the CU determines the proposed candidate cells (for example, according to RRM measurement). The CU sends the proposed candidate cell list to the candidate DU via an F1 message (e.g., a UE CONTEXT SETUP REQUEST message or other message) to request the candidate DU to configure or set up the candidate cells. This message may also include instructions indicating that the procedure is for L1 / L2 mobility and / or instructions indicating what type of L1 / L2 mobility the procedure is for. Prior to block 1102, in some embodiments, the CU may send a UE CONTEXT MODIFICATION REQUEST message to the source DU to query for the latest configuration. The source DU responds with a UE CONTEXT MODIFICATION RESPONSE message containing the complete configuration information.

[0129] In block 1104, the target DU decides whether to configure or set up the proposed candidate cells and sends the generated candidate cell configuration (e.g., CellGroupConfig) to the CU (e.g., via the UE CONTEXT SETUP RESPONSE message). If the target DU fails to configure some candidate cells, the DU may also include in the message a list of accepted cells (e.g., a list of cells that have already been successfully configured) or a list of failed / rejected cells (e.g., a list of cells that failed to be configured). In block 1106, the CU may send the configured candidate cell list to the source DU via an F1 message (e.g., the UE CONTEXT MODIFICATION REQUEST message). This message may also include trigger events / execution conditions generated by the CU (e.g., for mobility triggered by the DU). In block 1108, the source DU responds using the UE CONTEXT MODIFICATION RESPONSE message. This message may also include trigger events / execution conditions generated by the DU (e.g., for mobility triggered by the UE or mobility triggered by the CU).

[0130] In block 1110, the CU sends the generated RRCReconfiguration message to the DU (e.g., via a DL RRC MESSAGE TRANSFER message). The RRC message includes candidate cell configuration and may also include trigger events / conditions associated with the candidate cell (e.g., mobility triggered by the UE). In block 1112, the DU forwards the received RRCReconfiguration message to the UE. In block 1114, the UE responds to the DU with an RRCReconfigurationComplete message, to which the DU forwards it to the CU in block 1116 (e.g., via a UL RRC MESSAGE TRANSFER message). In some embodiments, blocks 1106 and 1108 may be skipped. In block 1104, the CU may send the generated RRC reconfiguration message to the source DU (e.g., via a UE CONTEXT MODIFICATION REQUEST message). This message may include the configured candidate cell list and / or trigger events / execution conditions generated by the CU (for example, in the case of mobility triggered by the DU).

[0131] Figure 12 illustrates an embodiment of inter-DU mobility based on candidate cell preparation initiated by a DU. Figure 12 is applicable to embodiments 3 and 4 from Table 4. Figure 5 illustrates inter-DU mobility, and Figure 12 illustrates inter-DU mobility based on candidate cell preparation initiated by a DU. In block 1202, the source DU determines candidate cells (e.g., according to an L1 measurement). The DU sends a proposed list of candidate cells and / or candidate DU IDs to the CU via an F1 message (e.g., a UE CONTEXT MODIFICATION REQUIRED message or other message) to request that the candidate cells be configured. This message may also include instructions indicating that the procedure is for L1 / L2 mobility, and / or instructions indicating what type of L1 / L2 mobility the procedure is for.

[0132] In block 1204, the CU sends a proposed list of candidate cells to the candidate DU via an F1 message (e.g., a UE CONTEXT SETUP REQUEST message or another message) to request the candidate DU to configure the candidate cells. This message may also include an indication that this procedure is for L1 / L2 mobility, such as an "L1 / L2 mobility" indicator. In some embodiments, prior to block 1204, the CU sends a UE CONTEXT MODIFICATION REQUEST message to the source DU to query for the latest configuration, and the source DU responds with a UE CONTEXT MODIFICATION RESPONSE message containing the complete configuration information.

[0133] In block 1206, the target DU decides whether to configure the proposed candidate cells and sends the generated candidate cell configuration (e.g., CellGroupConfig) to the CU (e.g., via the UE CONTEXT SETUP RESPONSE message). If the target DU fails to configure some candidate cells, the DU may also include in the message a list of accepted cells (e.g., a list of cells that have already been successfully configured) or a list of failed / rejected cells (e.g., a list of cells that failed to be configured). In block 1208, the CU sends the generated RRCReconfiguration message to the DU via an F1 message (e.g., the UE CONTEXT MODIFICATION CONFIRM message). The RRC message includes the candidate cell configuration and may also include trigger events / execution conditions associated with the candidate cells (e.g., for mobility triggered by the UE). The F1 message may include the configured candidate cell list and / or trigger events / conditions (e.g., for mobility triggered by the DU). In block 1210, the DU forwards the received RRCReconfiguration message to the UE. In block 1212, the UE responds to the DU with the RRCReconfigurationComplete message, to which the DU forwards it to the CU in block 1214 (for example, via the UL RRC MESSAGE TRANSFER message).

[0134] In some embodiments, after block 1206, the CU may send a UE CONTEXT MODIFICATION REQUEST message to the source DU to notify it of the configured / accepted candidate cell list. This message also includes a trigger event / execution condition generated by the CU (e.g., for mobility triggered by the DU), and the source DU responds to the CU with a UE CONTEXT MODIFICATION RESPONSE message. This message includes a trigger event / execution condition generated by the DU (e.g., for mobility triggered by the UE or mobility triggered by the DU), and the CU sends the generated RRCReconfiguration message to the source DU via an F1 message (e.g., a DL RRC MESSAGE TRANSFER message).

[0135] Figures 9-12 can be considered as part of the candidate cell setup initiation / preparation phase, and Figures 13-18 can be considered as part of the L1 / L2 mobility trigger phase. The overall L1 / L2 mobility procedure may be any combination of the candidate cell setup initiation / preparation phase and the L1 / L2 mobility trigger phase. There are several options for triggering L1 / L2 mobility. As mentioned above, there may be mobility triggered by the network (NW) or mobility triggered by the UE. For mobility triggered by the network (NW), it may be triggered by the command center (CU) or the command unit (DU). For mobility triggered by the CU, the CU sends the candidate cell to be activated / switched to the DU, and the DU sends an L1 / L2 command to the UE to indicate the candidate cell to be activated / switched. For mobility triggered by a DU, the DU sends an L1 / L2 command to the UE to indicate the candidate cell to be activated / switched, and after the completion of the L1 / L2 mobility (e.g., successful completion of RA to the DU, or successful reception of L1 / L2 signaling from the UE to the DU), the DU may notify the CU of the activated cell or target cell. In one embodiment, the DU notifies the CU of only the activated cell or target SpCell, but not the activated cell or target SCell. If all candidate cells are activated as SCells (i.e., the L1 / L2 mobility was triggered for the addition / modification of SCells), the DU does not need to notify the CU. In another embodiment, the DU notifies all candidate cells to be activated, including both SpCells and SCells.

[0136] In the case of mobility triggered by a UE, the UE directly triggers the L1 / L2 mobility when at least one of the execution conditions is met. After the completion of the L1 / L2 mobility (e.g., successful completion of RA to the DU, or successful reception of L1 / L2 signaling from the UE to the DU), the DU may notify the CU of the activated cell or target cell. In one embodiment, the DU notifies the CU of only the activated cell or target SpCell, but not the activated cell or target SCell. If all candidate cells have been activated as SCells (i.e., the L1 / L2 mobility has been triggered for the addition / modification of SCells), the DU should notify the CU. In another embodiment, the DU notifies all candidate cells to be activated, including both SpCells and SCells.

[0137] Figure 13 shows an embodiment of in-DU mobility based on decisions triggered by the CU. Figure 13 is applicable to Embodiments 1 and 4 from Table 4. Figure 4 shows in-DU mobility, and Figure 13 shows in-DU mobility based on decisions triggered by the CU. In block 1302, L1 / L3 measurement reports are provided from the UE to the DU and forwarded to the CU in block 1304. The measurement reports are used to determine candidate cells in block 1306. Blocks 1302-1306 have been described in other embodiments.

[0138] In block 1308, after the CU has determined candidate cells to be activated / switched according to, for example, L1 and / or L3 measurement reports or load balancing, the CU sends the candidate cells to be activated / switched to the DU via an F1 message (e.g., a UE CONTEXT MODIFICATION REQUEST message or other message). In block 1310, the DU sends an L1 / L2 command to the UE indicating the candidate cell to be activated / switched. In block 1312, the UE activates the target cell or accesses the target cell (e.g., via a random access procedure), and in block 1314, completes the L1 / L2 mobility procedure by sending L1 / L2 signaling (e.g., via ACK, UCI, MAC CE) to the DU. In block 1316, the DU responds to the CU (e.g., via a UE CONTEXT MODIFICATION RESPONSE message or other message). This message may include the activated cell ID or the target cell ID.

[0139] Figure 14 shows an embodiment of in-DU mobility based on a decision triggered by the DU. Figure 14 is applicable to Embodiments 2 and 3 from Table 4. Figure 4 shows in-DU mobility, and Figure 14 shows in-DU mobility based on a decision triggered by the DU. In block 1402, the UE provides an L1 measurement report to the DU. In block 1404, the DU determines, based on the measurement, a candidate cell to be activated. In block 1406, after the DU has determined the candidate cell to be activated / switched, the DU sends an L1 / L2 command to the UE to indicate the candidate cell to be activated / switched. In block 1408, the UE activates / accesses the target cell (e.g., via a random access procedure), and in block 1410, sends an L1 / L2 signaling to the DU to complete the L1 / L2 mobility procedure. In block 1412, the DU may notify the CU of the activated or target cell (e.g., via an ACCESS SUCCESS message).

[0140] Figure 15 shows an embodiment of in-DU mobility based on a decision triggered by the UE. Figure 4 shows in-DU mobility, and Figure 15 shows in-DU mobility based on a decision triggered by the UE. In block 1502, the UE evaluates the execution conditions for candidate cells. If at least one candidate cell satisfies the corresponding execution conditions, the UE applies / activates the corresponding candidate cell settings. In block 1504, the UE activates / accesses the target cell (e.g., via a random access procedure), and in block 1506, completes the L1 / L2 mobility procedure by sending L1 / L2 signaling (e.g., via ACK, UCI, MAC CE) to the DU. In block 1508, the DU notifies the CU of the successful completion of the L1 / L2 mobility (e.g., via an ACCESS SUCCESS message or other message). This message may include the activated cell ID or the target cell ID.

[0141] Figure 16 shows an embodiment of inter-DU mobility based on decisions triggered by the CU. Figure 16 is applicable to Embodiments 1 and 4 from Table 4. Figure 5 shows inter-DU mobility, and Figure 16 shows inter-DU mobility based on decisions triggered by the CU. In block 1602, L1 / L3 measurement reports are provided from the UE to the source DU and forwarded to the CU in block 1604. The measurement reports are used to determine candidate cells in block 1606. Blocks 1602-1606 have been described in other embodiments. In block 1608, the CU determines the candidate cells to be activated / switched (e.g., according to L1 and / or L3 measurement reports, or / or load conditions), and the CU sends the candidate cells to be activated / switched to the source DU via an F1 message (e.g., a UE CONTEXT MODIFICATION REQUEST message or other message). In block 1610, the source DU sends an L1 / L2 command to the UE indicating the candidate cells to be activated / switched. The source DU may also send a Downlink Data Delivery Status frame in block 1612 to notify the CU of any failed downlink data transmissions to the UE. In block 1614, the source DU responds to the CU (e.g., via a UE CONTEXT MODIFICATION RESPONSE message or other message). In block 1616, the UE activates or accesses the target cell (e.g., via a random access procedure), and in block 1622, sends L1 / L2 signaling to the DU to complete the L1 / L2 mobility procedure. After block 1616, the target DU may send a Downlink Data Delivery Status frame in block 1618 to notify the CU. Downlink packets may be sent from the CU to the target DU, including any PDCP PDUs that were not successfully transmitted within the source DU.The target DU may also notify the CU of the successful completion of L1 / L2 mobility in block 1620 (for example, via an access success ("ACCESS SUCCESS") message). This message may also include the activated cell or target cell.

[0142] Figure 17 shows an embodiment of inter-DU mobility based on decisions triggered by the DU. Figure 17 is applicable to embodiments 2 and 3 from Table 4. Figure 5 shows inter-DU mobility, and Figure 17 shows inter-DU mobility based on decisions triggered by the DU. In block 1702, the UE provides an L1 measurement report to the source DU. In block 1704, the source DU determines, based on the measurement, a candidate cell to be activated. In block 1706, after the source DU has determined the candidate cell to be activated / switched, the source DU sends an L1 / L2 command to the UE to indicate the candidate cell to be activated / switched. The source DU determines the candidate cell to be activated / switched (e.g., according to the L1 measurement report), and the source DU sends an L1 / L2 command to the UE to indicate the candidate cell to be activated / switched. The source DU may also send a downlink data delivery status frame in block 1708 to notify the CU of downlink data to the UE that failed to be transmitted. In block 1710, the UE activates the target cell or accesses the target cell (e.g., via a random access procedure), and in block 1716, completes the L1 / L2 mobility procedure by sending L1 / L2 signaling to the DU. After block 1710, the target DU may notify the CU by sending a downlink data delivery status frame in block 1712. Downlink packets may be sent from the CU to the target DU, including PDCP PDUs that were not successfully sent within the source DU. The target DU may also notify the CU of the successful completion of L1 / L2 mobility in block 1714 (e.g., via an ACCESS SUCCESS message). This message may also include the activated / target cell.

[0143] Figure 18 shows an embodiment of DU-to-DU mobility based on a decision triggered by the UE. Figure 5 shows DU-to-DU mobility, and Figure 18 shows DU-to-DU mobility based on a decision triggered by the UE. In block 1802, the UE evaluates the execution conditions for candidate cells. If at least one candidate cell satisfies the corresponding execution conditions, the UE applies / activates the corresponding candidate cell configuration. In block 1804, the UE activates the target cell or accesses the target cell (e.g., via a random access procedure), and in block 1810, sends L1 / L2 signaling to the DU to complete the L1 / L2 mobility procedure. After block 1804, the target DU may notify the CU by sending a downlink data delivery status frame in block 1806. Downlink packets may be sent from the CU to the target DU, including PDCP PDUs that were not successfully sent within the source DU. The target DU may also notify the CU of the successful completion of L1 / L2 mobility in block 1808 (for example, via the ACCESS SUCCESS message). This message may also include the activated cell or target cell.

[0144] In block 1812, the CU may also initiate a UE context modification procedure to the source DU to stop transmitting data about the UE. The CU sends a UE CONTEXT MODIFICATION REQUEST message to the source DU instructing it to stop transmitting data about the UE. The source DU also sends a downlink data delivery status frame in block 1814 to notify the CU of the downlink data to the UE that failed to be transmitted. In block 1822, the source DU responds to the CU with a UE CONTEXT MODIFICATION RESPONSE message. In some embodiments, downlink user data is provided by the CU to the candidate DU in block 1816 and to the UE in block 1818. In block 1820, uplink user data is provided from the UE to the source DU.

[0145] Control of L1 / L2 mobility triggers

[0146] The CU can control whether the DU is allowed to trigger L1 / L2 mobility (i.e., send L1 / L2 mobility trigger commands to the UE). If the CU decides to stop / suspend L1 / L2 mobility triggering (for example, when the CU decides to trigger L3 mobility via a conventional HO (i.e., PCell change), DAPS HO, conventional PSCell addition / modification, etc.), the CU sends an instruction (e.g., an "L / L2 mobility triggering indicator," which is set to "stop / suspend") via an F1 message (e.g., a UE CONTEXT MODIFICATION REQUEST message or other message) to indicate to the DU that L1 / L2 mobility triggering should be stopped / suspended. Upon / after receiving that instruction, the DU should not send L1 / L2 mobility trigger commands to the UE. If the CU decides to restart / reboot the L1 / L2 mobility trigger (for example, upon completion of L3 mobility), the CU sends an instruction (e.g., an "L / L2 mobility triggering indicator," which is set to "restart / resume") via an F1 message (e.g., a UE CONTEXT MODIFICATION REQUEST message or other message) to the DU to restart / reboot the L1 / L2 mobility trigger. Upon / after receiving that instruction, the DU may restart sending L1 / L2 mobility trigger commands to the UE, for example, when it is determined that a trigger event has been met.

[0147] The DU may request that the L1 / L2 mobility trigger be restarted / restarted, for example, if it is determined that a trigger event has been met. The DU sends an instruction (e.g., an "L / L2 mobility triggering request indicator") to the CU to allow the restart of the L1 / L2 mobility trigger via an F1 message (e.g., a UE CONTEXT MODIFICATION REQUIRED message or another message). The CU decides whether to accept the request and sends a response to the DU via an F1 message (e.g., a UE CONTEXT MODIFICATION CONFIRM or UE CONTEXT MODIFICATION REFUSE message). If the CU rejects the request, it may also include the reason (e.g., L3 mobility triggered) in the response message.

[0148] Mobility interactions

[0149] In alternative embodiments, L1 / L2 mobility may interact with other functions such as handover (HO), conditional handover (CHO), conditional PSCell addition / modification (CPAC), dual active protocol stack (DAPS), or other functions. In one embodiment, the L1 / L2 mobility configuration may include these other functions. L1 / L2 mobility may be combined with CHO / CPAC (i.e., L1 / L2 mobility triggered by the UE), where the UE automatically triggers L1 / L2 mobility based on pre-configured execution conditions and stored candidate cell configurations. In another example, L1 / L2 mobility may be combined with DAPS so that the UE maintains source cell connectivity when triggering L1 / L2 mobility to a target candidate cell.

[0150] In alternative embodiments, these other functions may be modified to include L1 / L2 mobility settings. For example, conventional HO, conventional PSCell Add / Modify, CHO, CPAC, DAPS, or HO settings may be modified to include candidate cell settings for L1 / L2 mobility. In other words, the L1 / L2 mobility settings are based on the target cell settings, and the L1 / L2 mobility can be executed (if triggered) after the completion of other functions. Alternatively, L1 / L2 mobility and other functions may be configured independently in the UE.

[0151] If L1 / L2 mobility is already configured (i.e., the UE has a stored candidate cell configuration), the source cell / node may want to initiate or prepare L3 PCell changes (e.g., traditional HO, CHO, DAPS, etc.) and / or L3 PSCell additions / modifications (e.g., traditional PSCell additions / modifications, CPAC, etc.). The source cell / node may send information to the target cell / node to transfer / maintain / remove candidate cell configurations. In one embodiment, this information may include candidate cell configurations, e.g., candidate cell ID and each cell configuration. In some embodiments, there may be a list of candidate cells to be maintained / removed. In another embodiment, this information may include instructions on whether to maintain / remove candidate cell configurations within the configurations of other functions. For example, these instructions may indicate whether to maintain / remove candidate PCell configurations, candidate PSCell configurations, candidate SpCell configurations and / or candidate SCell configurations (e.g., "maintainCandidatePCell", "maintainCandidatePSCell", "maintainCandidateSpCell", "maintainCandidateSCell"). In another embodiment, this information may include instructions on which candidate cell settings may be considered baselines / references for the delta settings of target cell settings in the settings of other functions (for example, this instruction indicates one or more candidate cell IDs as baseline cells). For example, this instruction may indicate which candidate cell settings may be considered baselines / references for the delta settings of target PCell, target PSCell, target SpCell, and / or target SCell (e.g., "baselineForPCell", "baselineForPSCell", "baselineForSpCell", "baselineForSCell"). Other functions may have different settings (e.g., conventional HO / conventional PSCell add / modify / CHO / CPAC / DAPS HO settings).

[0152] In embodiments where information is provided, the information may be included in an Xn / X2 message (e.g., an HO request message, an SN addition request message, or an SN change required message) and forwarded directly to the target cell / node. In another embodiment, the information may be provided in an RRC message (e.g., a HandoverPreparationInformation, CG-Config, or CG-ConfigInfo message). This RRC message may be included as a single information element within an Xn / X2 message.

[0153] If another function is triggered or executed first, there may be alternatives for handling stored L1 / L2 mobility settings. In one embodiment, the UE may remove stored L1 / L2 mobility settings (e.g., candidate cell settings). For example, the UE may remove stored L1 / L2 mobility settings in accordance with explicit instructions from the source cell, where the source cell explicitly releases the candidate cell settings via an RRC message (e.g., an RRC reset message) before sending an HO / PSCell add / modify command to the UE. In an alternative embodiment, the UE may remove stored L1 / L2 mobility settings in accordance with explicit instructions from the target cell. For example, the target cell explicitly releases the candidate cell settings within a command for another function (e.g., including instructions in an RRC reset message indicating the removal of stored candidate cell settings). In another example, the target cell may explicitly indicate within a command for another function which candidate cell settings should be released (e.g., including a list of candidate cells to be released in an RRC reset message). In another example, the UE voluntarily removes stored L1 / L2 mobility settings when the execution of another function is triggered, for example, when it receives an L3 mobility command (e.g., an RRC reset message for adding / modifying HO and / or PSCell), or when it triggers the execution of conditional L3 mobility (e.g., when the execution conditions for CHO / CPAC are met). In yet another example, the UE voluntarily removes stored L1 / L2 mobility settings when the execution of another function is completed, for example, when RA to the target cell is completed.

[0154] In other embodiments where other functions are initially triggered or executed, the L1 / L2 mobility settings may be maintained by the UE through stored L1 / L2 mobility settings. For example, the UE maintains stored L1 / L2 mobility settings in accordance with explicit instructions from the target cell. These explicit instructions may come from the target cell and may explicitly instruct other functions to maintain candidate cell settings within their commands (e.g., including instructions to maintain stored candidate cell settings within an RRC reset message). In another example, the target cell explicitly instructs other functions which candidate cell settings should be maintained within their commands (e.g., including a list of candidate cells to be released / maintained within an RRC reset message).

[0155] In another embodiment, the UE may maintain stored L1 / L2 mobility settings without explicit instruction. If the L1 / L2 mobility settings are maintained, other functions may be triggered / executed first, as described above. The handling of execution condition evaluation (i.e., in the case of L1 / L2 mobility triggered by the UE) may be handled when the execution of other functions is triggered. For example, the UE may automatically stop evaluating execution conditions (e.g., for all candidate cells, for L1 / L2 mobility candidate cells in the MCG, or for L1 / L2 mobility candidate cells in the SCG). Alternatively, the UE may stop evaluating execution conditions in accordance with explicit instructions from the network (e.g., target cells). These instructions may be explicitly instructed in an RRC message (e.g., an RRC reset message) or MAC CE to stop evaluating execution conditions for candidate cells (e.g., for all candidate cells, for L1 / L2 mobility candidate cells in the MCG, or for L1 / L2 mobility candidate cells in the SCG).

[0156] If the UE successfully completes the execution of other functions (e.g., completion of RA to the target cell), the UE may remove the stored L1 / L2 mobility settings. Alternatively, the UE may restart the evaluation of execution conditions for L1 / L2 mobility triggered by the UE (e.g., for all candidate cells, for L1 / L2 mobility candidate cells in the MCG only, or for L1 / L2 mobility candidate cells in the SCG only).

[0157] In some embodiments, the removal of stored L1 / L2 mobility settings may depend on the type of function performed. For example, if the function is related to the MCG (e.g., HO / CHO / DAPS), the UE may remove only the L1 / L2 mobility settings in the MCG, only the L1 / L2 mobility settings in the SCG, or all L1 / L2 mobility settings in both the MCG and SCG (i.e., all candidate cell settings). In another example, if the function is related to the SCG (e.g., PSCell Add / Modify / CPACS), the UE may remove only the L1 / L2 mobility settings in the MCG, only the L1 / L2 mobility settings in the SCG, or all L1 / L2 mobility settings in both the MCG and SCG (i.e., all candidate cell settings).

[0158] The embodiments described above relate to L1 / L2 mobility being triggered first. In alternative embodiments, other functions may be triggered or executed first. Different alternatives may exist, such as when other functions are triggered first, for example, when CHO / CPAC and L1 / L2 mobility are configured independently for the UE (e.g., the UE stores both the CHO / CPAC candidate cell settings and the L1 / L2 mobility candidate cell settings), or when the UE triggers L1 / L2 mobility (e.g., by receiving an L1 / L2 command triggered by the NW, or by triggering the execution of L1 / L2 mobility triggered by the UE). Alternatives include whether the UE removes the stored CHO / CPAC settings, or whether the UE retains the stored CHO / CPAC settings but stops evaluating the CHO / CPAC. If the UE successfully completes L1 / L2 mobility (e.g., completion of RA to the target cell, or transmission of L1 / L2 signaling to the target cell), the UE may remove the stored CHO / CPAC settings. Alternatively, the UE may restart the CHO / CPAC evaluation. In some embodiments, the removal of stored CHO / CPAC settings may depend on the type of L1 / L2 mobility being performed. For example, if the L1 / L2 mobility is for cell changes within the MCG (e.g., PCell change, MCG SCell addition / modification), the UE may remove only the CHO settings, only the CPAC settings, or both the CHO and CPAC settings. In another example, if the L1 / L2 mobility is for cell changes within the SCG (e.g., PSCell addition / modification, SCG SCell addition / modification), the UE may remove only the CPAC settings, or both the CHO and CPAC settings.

[0159] The embodiments described above relate to either L1 / L2 mobility being triggered first, or other functions being triggered first. However, there are also embodiments in which other functions and L1 / L2 mobility are triggered simultaneously, or substantially simultaneously. If the trigger conditions for CHO / CPAC and L1 / L2 mobility are met simultaneously (for example, if the UE detects that the CHO / CPAC execution conditions have been met and the L1 / L2 mobility execution conditions have been met, or if it receives an L1 / L2 mobility command from the NW), the UE may execute one function first according to the following alternative priorities. ● CHO>L1 / L2 Mobility for PCell Change>CPAC>L1 / L2 Mobility for PSCell Change>L1 / L2 Mobility for SCell Change ● L1 / L2 Mobility for PCell Change > CHO > L1 / L2 Mobility for PSCell Change > CPAC > L1 / L2 Mobility for SCell Change.

[0160] Handling failures in mobility interactions

[0161] If conditional L3 mobility (e.g., CHO, CPAC) and L1 / L2 mobility are set simultaneously, when an L1 / L2 mobility failure is detected, the UE may continue evaluating the conditional L3 mobility and, when the execution conditions (e.g., conditional L3 mobility execution conditions or additional pre-configured thresholds for failure recovery) are met, select one candidate cell for conditional L3 mobility and execute the conditional L3 mobility. In one embodiment, when L1 / L2 mobility is detected for a PCell change failure, the UE continues evaluating the CHO and, when the execution conditions (e.g., CHO execution conditions or additional pre-configured thresholds for failure recovery) are met, select one candidate cell for CHO and execute the CHO. In another embodiment, when L1 / L2 mobility is detected for a PSCell change failure, the UE continues evaluating the CPAC and, when the execution conditions (e.g., CPAC execution conditions or additional pre-configured thresholds for failure recovery) are met, select one candidate cell for CPAC and execute the CPAC.

[0162] Measurement and handling for conditional mobility

[0163] In conditional mobility (e.g., L1 / L2 mobility triggered by CHO, CPAC, UE), the network (e.g., MN, SN) may generate / configure individual measurement gaps for the UE and send them to the UE via RRC signaling (e.g., an RRCReconfiguration message with conditional mobility settings). For example, a conditional reconfiguration-related measurement gap (e.g., conditionalReconfigurationGap) is introduced within an existing conditionalReconfiguration IE. The conditional reconfiguration-related measurement gap is used by the UE only during the evaluation of conditional mobility. During conditional mobility preparation, the source nodes (e.g., source SN, source MN) may send the original / source measurement gap settings to the target nodes (e.g., target SN, target MN). The target nodes generate measurement gaps for candidate cells (i.e., measurement gap settings included within the candidate cell settings) based on the original / source measurement gap settings.

[0164] When the UE receives a conditional reset-related measurement gap, the UE may ignore the original / source measurement gap, but may store two sets of measurement gap settings (i.e., the original measurement gap setting and the conditional reset-related measurement gap). When the execution of conditional mobility is triggered, the UE applies the measurement gap setting to the candidate cell based on the original / source measurement gap setting. Upon successful completion of conditional mobility, or when the execution of conditional mobility is triggered, the UE may remove the conditional reset-related measurement gap.

[0165] Mobility interactions in idle / inactive states

[0166] There are several alternative embodiments for handling L1 / L2 mobility settings (e.g., candidate cell settings) when a UE enters the RRC_INACTIVE / IDLE state. In the first embodiment, the NW explicitly indicates, via RRC signaling, whether to store / maintain / retain or remove candidate cell settings when the UE enters the RRC_INACTIVE / IDLE state (e.g., by including an indicator in the RRCRelease message). Based on the explicit indication, the UE stores / maintains / retains or removes the stored candidate cell settings when entering the RRC_INACTIVE / IDLE state. In the second embodiment, the NW explicitly indicates, via RRC signaling, which candidate cell settings can be stored / maintained / retained or removed when the UE enters the RRC_INACTIVE / IDLE state (e.g., by including a list of cell IDs to be maintained or a list of cell IDs to be removed in the RRCRelease message). Based on the explicit indication, the UE stores / maintains / retains or removes the indicated candidate cell settings when entering the RRC_INACTIVE / IDLE state. In the third embodiment, when the UE enters the RRC_INACTIVE / IDLE state (for example, when it receives an RRCRelease message that includes / does not include suspendConfig), the UE voluntarily deletes the stored candidate cell configuration. In the fourth embodiment, when the UE enters the RRC_INACTIVE / IDLE state, it retains the stored candidate cell configuration.

[0167] If the L1 / L2 mobility configuration is maintained during RRC_INACTIVE, there are several alternative embodiments for handling the stored configuration when the RRC connection is resumed (e.g., transition from the RRC_INACTIVE state to the RRC_CONNECTED state). In the first embodiment, the NW explicitly instructs the UE via RRC signaling to reactivate / activate one or more candidate cells (e.g., including the IDs of one or more candidate cells to be reactivated / activated in the RRCResume message). Based on the explicit instruction, the UE reactivates / activates the instructed candidate cells upon receiving the RRC signaling. In the second embodiment, the NW explicitly instructs the UE to restore one or more candidate cell configurations, which may serve as a baseline for subsequent delta configurations for adding / modifying serving cells (e.g., including the IDs of one or more candidate cells to be restored in the RRCResume message). Alternatively, the delta configuration based on the indicated cell configuration may be included via RRC signaling. Based on explicit instructions, the UE restores the specified candidate cell configuration upon receiving RRC signaling. The UE may also apply the received delta configuration based on the specified cell configuration (if any).

[0168] Multi-connection

[0169] L1 / L2-based inter-cell mobility mechanisms may also be used in multi-connectivity architectures (i.e., multiple cell group configurations can be pre-configured by the network). Multi-connectivity may be referred to as Multi-Radio Dual Connectivity (MR-DC). The embodiments described throughout may be applied to any multi-connectivity / MR-DC environment or architecture. Here, “candidate cell” may be referred to as “candidate cell group” (e.g., MCG, SCG) for multi-connectivity / MR-DC. Dynamic cell group activation / switching may be triggered by the network via RRC signaling (e.g., RRC reconfiguration message) or L1 / L2 commands (e.g., DCI, MAC CE). The UE may also trigger cell group activation / switching based on pre-configured execution conditions and candidate cell group configurations. Applying this embodiment to multi-connectivity / MR-DC may include selective activation / switching. Here, “candidate cell” may be referred to as “candidate cell group” (e.g., MCG, SCG) for multi-connectivity / MR-DC.

[0170] The systems and processes described above may be encoded in a computer-readable medium such as a signaling medium or memory, programmed in a device such as one or more integrated circuits or one or more processors, or processed by a controller or computer. This data may be analyzed within a computer system and used to generate a spectrum. If the method is performed by software, the software may reside in memory that is embedded in or interconnected with a storage device, synchronous device, communication interface, or non-volatile or volatile memory that communicates with the transmitter. Circuits or electronic devices are provided to transmit data to another location. Memory may contain an ordered list of executable instructions for realizing a logical function. The described logical function or system element may be realized through optical circuits, digital circuits, source code, analog circuits, analog sources such as analog electrical, audio, or video signals, or a combination thereof. The software may be realized in any computer-readable or signaling medium for use by or in connection with an instruction-executable system, device, or apparatus. Such a system may include a computer-based system, a system with a processor, or another system that may selectively obtain instructions from an instruction-executable system, device, or apparatus capable of executing instructions.

[0171] "Computer-readable media," "machine-readable media," "propagating signal" media, and / or "signal transmission media" may include any device that stores, communicates, propagates, or transmits software used by or in connection with an instruction-executable system, device, or apparatus. Machine-readable media may optionally be, but are not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, apparatus, or propagating media. A non-exhaustive list of examples of machine-readable media includes electrical connections having one or more wires, portable magnetic disks or optical disks, random access memory "RAM," read-only memory "ROM," volatile memory such as erasable programmable read-only memory (EPROM or flash memory), or optical fibers. Machine-readable media may also include tangible media on which software is printed, since software may be stored electronically as an image or in another form (e.g., through optical scanning), compiled, and / or interpreted or otherwise processed. The processed media may then be stored in a computer and / or machine memory.

[0172] The illustrations of embodiments described herein are intended to provide a general understanding of the configurations of various embodiments. The illustrations do not fully illustrate all elements and features of apparatuses and systems utilizing the configurations or methods described herein. Many other embodiments may be obvious to those skilled in the art when reading this disclosure. Other embodiments can be utilized and derived from this disclosure so that constituent and logical substitutions and modifications can be made without departing from the scope of this disclosure. Furthermore, the illustrations are merely representative and may not be drawn to scale. Certain proportions in the illustrations may be exaggerated, and other proportions may be minimized. Therefore, this disclosure and drawings should be considered illustrative rather than restrictive.

[0173] In this specification, one or more embodiments of the present disclosure may be referred to individually and / or collectively by the term “invention” for convenience only and without the intention to limit the scope of the application to any particular invention or inventive concept. Furthermore, while specific embodiments are illustrated and described herein, it should be understood that any subsequent arrangements designed to achieve the same or similar objectives may substitute for the specific embodiments shown. This disclosure is intended to cover all subsequent adaptations or variations of the various embodiments. Combinations of the above embodiments with other embodiments not specifically described herein will become apparent to those skilled in the art upon reading the specification.

[0174] "To be connected" means to be directly connected or indirectly connected through one or more intermediate components. Such intermediate components may include both hardware and software-based components. The arrangement and types of components may be modified without departing from the gist or scope of the claims described herein. Additional components, different components, or fewer components may be provided.

[0175] The subject matter disclosed above should be considered illustrative and not restrictive, and the appended claims are intended to cover all modifications, extensions, and other embodiments that fall within the true essence and scope of the invention. Therefore, the scope of the invention is determined, to the extent permitted by law, by the broadest permissible interpretation of the following claims and their equivalents, and is not limited or restricted by the above detailed description. While various embodiments of the invention have been described, it will be apparent to those skilled in the art that many more embodiments and realizations are possible within the scope of the invention. Therefore, the invention is not limited except with regard to the appended claims and their equivalents.

Claims

1. A method for wireless communication, The user equipment (UE) receives a configuration message from the base station that includes a list of candidate cells, wherein each candidate cell in the list of candidate cells has a configuration and a candidate cell configuration index corresponding to the configuration. To transmit a measurement report, including Layer 1 ("L1") measurements, to the base station for at least one candidate cell from the candidate cell list, The base station receives a Media Access Control Element (MAC CE) command that includes the candidate cell setting index of the target cell in the candidate cell list and the Transmit Setting Indicator (TCI) status of the target cell, To transmit a communication to the target cell based on the MAC CE command and the settings of the target cell, A method that includes this.

2. The MAC CE command further includes at least one of a timing advance (TA) value or a synchronization signal block (SSB) identifier (ID) associated with the target cell. The method according to claim 1.

3. The configuration message includes at least one of the following: physical cell identity ("PCI"), reference signal ("RS") ID associated with the candidate cell, or transmit configuration indicator ("TCI") status ID associated with the candidate cell. The method according to claim 1.

4. Applying the stored cell settings of the target cell, or Performing mobility from the current serving cell to the target cell, or When inter-cell mobility based on Layer 1 (L1) / L2 is triggered, a timer for mobility is started, wherein the timer is a radio resource control ("RRC") layer timer T304. The method according to claim 1, further comprising at least one of the following.

5. When it is notified that the inter-cell mobility based on L1 / L2 has been successfully completed, the timer is stopped. The method according to claim 4.

6. Based on the expiration of the timer, a failure regarding the mobility is determined, or Select another cell from the aforementioned candidate cells and perform mobility to the selected other cell. The method according to claim 4, further comprising:

7. When entering an idle state, or when an RRC release message is received that commands the suspension of the RRC connection, the stored candidate cell settings are removed. The method according to claim 1, further comprising:

8. A method for wireless communication, The base station transmits a configuration message to the user equipment (UE) including a list of candidate cells, wherein each candidate cell in the list of candidate cells has a configuration and a candidate cell configuration index corresponding to the configuration. The UE receives a measurement report, including a Layer 1 ("L1") measurement, for at least one candidate cell from the candidate cell list. Sending a Media Access Control Element (MAC CE) command to the UE, which includes the candidate cell setting index of the target cell in the candidate cell list and the transmission setting indicator (TCI) status of the target cell, Receiving communication from the target cell based on the MAC CE command and the settings of the target cell, Methods that include...

9. The MAC CE command further includes at least one of a timing advance (TA) value or a synchronization signal block (SSB) identifier (ID) associated with the target cell. The method according to claim 8.

10. The configuration message information includes at least one of the following: physical cell identity ("PCI"), reference signal ("RS") ID associated with the candidate cell, or transmit configuration indicator ("TCI") status ID associated with the candidate cell. The method according to claim 8.

11. A first wireless communication device comprising a processor and memory, The processor reads the code from the memory, Receiving a configuration message from a base station that includes a list of candidate cells, wherein each candidate cell in the list of candidate cells has a configuration and a candidate cell configuration index corresponding to the configuration. To transmit a measurement report, including Layer 1 ("L1") measurements, to the base station for at least one candidate cell from the candidate cell list, The base station receives a Media Access Control Element (MAC CE) command that includes the candidate cell setting index of the target cell in the candidate cell list and the Transmit Setting Indicator (TCI) status of the target cell, To transmit a communication to the target cell based on the MAC CE command and the settings of the target cell. The first wireless communication device to realize this.

12. The MAC CE command further includes at least one of a timing advance (TA) value or a synchronization signal block (SSB) identifier (ID) associated with the target cell. The first wireless communication device according to claim 11.

13. The configuration message includes at least one of the following: physical cell identity ("PCI"), reference signal ("RS") ID associated with the candidate cell, or transmit configuration indicator ("TCI") status ID associated with the candidate cell. The first wireless communication device according to claim 11.

14. Applying the stored cell settings of the target cell, or Performing mobility from the current serving cell to the target cell, or When inter-cell mobility based on Layer 1 (L1) / L2 is triggered, a timer for mobility is started, wherein the timer is a radio resource control ("RRC") layer timer T304. The first wireless communication device according to claim 11, further comprising at least one of the following.

15. When it is notified that the inter-cell mobility based on L1 / L2 has been successfully completed, the timer is stopped. The first wireless communication device according to claim 14.

16. Based on the expiration of the timer, a failure regarding the mobility is determined, or Select another cell from the aforementioned candidate cells and perform mobility to the selected other cell. The first wireless communication device according to claim 14, further comprising:

17. When entering an idle state, or when an RRC release message is received that commands the suspension of the RRC connection, the stored candidate cell settings are removed. The first wireless communication device according to claim 11, further comprising:

18. A second wireless communication device comprising a processor and memory, The processor is configured to read code from the memory and implement the method described in claim 8. The second wireless communication device.

19. The MAC CE command further includes at least one of a timing advance (TA) value or a synchronization signal block (SSB) identifier (ID) associated with the target cell. The second wireless communication device according to claim 18.

20. The configuration message information includes at least one of the following: physical cell identity ("PCI"), reference signal ("RS") ID associated with the candidate cell, or transmit configuration indicator ("TCI") status ID associated with the candidate cell. The second wireless communication device according to claim 18.

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