# US 12,114,334 B1 · Method and apparatus for preamble transmission based on the first PDCCH order and the second PDCCH order in mobile wireless communication system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,114,334 B1 - Document ID: US12114334B1 - Status: Granted - Kind: B1 - Application number: 18/604,373 - Filed: 2024-03-13 - Published: 2024-09-19 - Granted: 2024-10-08 - Earliest claimed: 2023-03-14 - Assignees: Blackpin Inc.; Soenghun Kim; Signalis Co., Ltd. - Applicants: BLACKPIN Inc.; Soenghun Kim; Signalis Co., Ltd. - Inventors: Soenghun Kim - Web page: https://patentgrep.com/patent/US12114334B1 ## CPC - H04W 72/231: the control data signalling from the layers above the physical layer, e.g. RRC or MAC-CE signalling - H04L 27/26025: {Numerology, i.e. varying one or more of symbol duration, subcarrier spacing, Fourier transform size, sampling rate or down-clocking (allocating sub-channels of the transmission path H04L5/003)} - H04W 8/24: Transfer of terminal data - H04W 56/0045: {compensating for timing error by altering transmission time} - H04W 72/1273: of downlink data flows - H04W 74/0833: Random access procedures, e.g. with 4-step access - H04W 36/0055: {Transmission or use of information for re-establishing the radio link} - H04W 72/23: in the downlink direction of a wireless link, i.e. towards a terminal - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A method and apparatus for layer 2 mobility is provided. Method for lower layer mobility includes transmitting the UECapabilityInformation to the base station, receiving a RRCReconfigruation from the base station, receiving a PDCCH order from the base station and transmitting a preamble to the base station based on the PDCCH order. The RRCReconfiguration includes a UE specific search space configuration information for type1 PDCCH order monitoring and a first RNTI for type1 PDCCH order monitoring and common search space identifier for type2 PDCCH order monitoring and a second RNTI for type2 PDCCH order monitoring. The RRCReconfiguration includes one or more inner RRCReconfiguration and associated mobility group identifier. ## Claims ### Claim 1 A method performed by a user device, the method comprising: transmitting, to a base station, capability information associated with the user device; receiving, from the base station, a first radio resource control (RRC) message, wherein the first RRC message comprises: at least one configuration parameter associated with a serving cell; and at least one configuration parameter associated with layer-1/layer-2 triggered mobility (LTM); receiving, from the base station, downlink control information (DCI) associated with a physical downlink control channel (PDCCH) order, wherein the DCI comprises: a first field comprising a value associated with the PDCCH order; and a second field configured to comprise a first value associated with the serving cell or a second value associated with a LTM candidate cell; based on the second value being comprised in the second field, transmitting, to the LTM candidate cell, a random access preamble; and after transmitting the random access preamble, receiving a second message comprising a timing advance value associated with the LTM candidate cell. ### Claim 2 (depends on 1) The method of claim 1, wherein the first RRC message comprises: search space configuration information for monitoring a PDCCH order of a first type; search space configuration information for monitoring a PDCCH order of a second type; a first radio network temporary identifier (RNTI) associated with the PDCCH order of the first type; and a second RNTI associated with the PDCCH order of the second type. ### Claim 3 (depends on 1) The method of claim 1, wherein the first RRC message comprises a plurality of RRC reconfiguration messages, and wherein each of the plurality of RRC reconfiguration messages comprises at least one configuration parameter associated with a respective LTM candidate cell. ### Claim 4 (depends on 1) The method of claim 1, further comprising: determining, based on the first value comprised in the second field of the DCI, a PDCCH order, of a first type, associated with the serving cell; or determining, based on the second value comprised in the second field of the DCI, a PDCCH order, of a second type, associated with the LTM candidate cell. ### Claim 5 (depends on 1) The method of claim 1, wherein the first RRC message is received via a first cell of a serving cell group, and wherein the second message is received via the first cell. ### Claim 6 (depends on 5) The method of claim 5, wherein the serving cell is the first cell. ### Claim 7 (depends on 5) The method of claim 5, wherein the second message is comprised in a medium access control protocol data unit (MAC PDU), and wherein the second message comprises a medium access control (MAC) control element (CE) indicating a switching from the first cell to the LTM candidate cell. ### Claim 8 (depends on 1) The method of claim 1, wherein the LTM candidate cell is an SpCell of a candidate cell group. ### Claim 9 (depends on 1) The method of claim 1, wherein the second message comprises: a field indicating an identity of the LTM candidate cell; a timing advance command field indicating the timing advance value that is associated with an amount of timing adjustment; and a synchronization signal/physical broadcast channel (SS/PBCH) index field. ### Claim 10 (depends on 1) The method of claim 1, wherein the DCI further comprises a random access preamble index field. ### Claim 11 (depends on 1) The method of claim 1, wherein the first RRC message comprises at least one configuration parameter for a candidate mobility group (CMG), wherein the CMG is a candidate cell group comprising a plurality of LTM candidate cells, and wherein the candidate cell group comprises a candidate SpCell. ### Claim 12 (depends on 1) The method of claim 1, wherein the at least one configuration parameter associated with LTM comprises an RRC reconfiguration (RRCReconfiguration) message for an LTM candidate cell. ### Claim 13 (depends on 12) The method of claim 12, wherein the RRCReconfiguration message for the LTM candidate cell comprises a medium access control (MAC) cell group configuration (MAC-CellGroupConfig) for the LTM candidate cell. ### Claim 14 (depends on 13) The method of claim 13, wherein the MAC-CellGroupConfig for the LTM candidate cell comprises at least one of: timing advance group configuration information for the LTM candidate cell; or at least one discontinuous reception (DRX) configuration (DRX-Config) for the LTM candidate cell. ### Claim 15 (depends on 1) The method of claim 1, wherein the capability information comprises at least one parameter indicating the user device supports LTM. ### Claim 16 (depends on 1) The method of claim 1, wherein the first RRC message is an RRC reconfiguration (RRCReconfiguration) message comprising at least one inner RRCReconfiguration message. ### Claim 17 (depends on 1) The method of claim 1, wherein the second field of the DCI indicates an identifier of the LTM candidate cell. ### Claim 18 (depends on 1) The method of claim 1, wherein the first field of the DCI is a frequency domain resource assignment field. ### Claim 19 (depends on 1) The method of claim 1, further comprising: determining a subcarrier spacing (SCS) of an uplink transmission from the user device, wherein the SCS is associated with an amount of time alignment for a timing advance group (TAG), and wherein the TAG is associated with the LTM candidate cell. ### Claim 20 (depends on 19) The method of claim 19, wherein the uplink transmission comprises a preamble transmission.