# US 11,452,142 B2 · Random access method, terminal, and network device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,452,142 B2 - Document ID: US11452142B2 - Status: Granted - Kind: B2 - Application number: 17/094,647 - Filed: 2020-11-10 - Published: 2021-02-25 - Granted: 2022-09-20 - Earliest claimed: 2018-05-10 - Assignees: Vivo Mobile Communication Co., Ltd. - Applicants: Vivo Mobile Communication Co., Ltd. - Inventors: Li Chen - Web page: https://patentgrep.com/patent/US11452142B2 ## CPC - H04W 74/006: {in the downlink, i.e. towards the terminal} - H04W 72/23: in the downlink direction of a wireless link, i.e. towards a terminal - H04W 74/002: {Transmission of channel access control information} - H04W 74/0833: Random access procedures, e.g. with 4-step access - H04L 41/0803: Configuration setting - H04W 48/12: using downlink control channel - H04W 72/0453: Resources in frequency domain, e.g. a carrier in FDMA - H04W 74/0838: using contention-free random access [CFRA] - H04W 84/042: {Public Land Mobile systems, e.g. cellular systems} - Y02D 30/70: in wireless communication networks - 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) - Y02D: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE ## Abstract The present disclosure provides a random access method, a terminal, and a network device. The random access method of the present disclosure comprises: receiving configuration information concerning a currently activated downlink bandwidth part (BWP) or a serving cell; detecting a random access response (RAR) in a random access procedure according to the configuration of a control resource set (CORESET) in the configuration information of the currently activated downlink BWP or the configuration information of the serving cell. ## Claims ### Claim 1 A random access method applied to a terminal, comprising: receiving configuration information of a currently active downlink bandwidth part BWP or a serving cell; and monitoring a random access response RAR in a random access process based on a configuration of a control resource set CORESET in the configuration information of the currently active downlink BWP or the configuration information of the serving cell; wherein the step of monitoring a random access response RAR in a random access process based on a configuration of a control resource set CORESET in the configuration information of the currently active downlink BWP or the configuration information of the serving cell comprises: monitoring the random access response RAR in the random access process based on a configuration of a default CORESET 0 in a case that no CORESET is explicitly configured on the currently active downlink BWP or the serving cell. ### Claim 2 (depends on 1) The random access method according to claim 1, wherein the step of monitoring the random access response RAR in the random access process based on a configuration of a default CORESET 0 comprises: when the default CORESET 0 is configured on the currently active downlink BWP or the serving cell, monitoring the RAR in the random access process by directly falling back to the default CORESET 0 of the currently active downlink BWP or the serving cell. ### Claim 3 (depends on 1) The random access method according to claim 1, wherein the step of monitoring the random access response RAR in the random access process based on a configuration of a default CORESET 0 comprises: when the default CORESET 0 is not configured on the currently active downlink BWP or the serving cell, falling back to a first downlink BWP, and monitoring the RAR in the random access process on a default CORESET 0 on the first downlink BWP; or when the default CORESET 0 is configured on the currently active downlink BWP or the serving cell, falling back to a first downlink BWP, and monitoring the RAR in the random access process on a default CORESET 0 on the first downlink BWP, wherein the first downlink BWP comprises: an initial downlink BWP, or a non-initial downlink BWP configured with a default CORESET. ### Claim 4 (depends on 3) The random access method according to claim 3, wherein before the falling back to a first downlink BWP, the method further comprises: sending a preamble on a currently active uplink bandwidth part BWP. ### Claim 5 (depends on 3) The random access method according to claim 3, wherein after the falling back to a first downlink BWP, the method further comprises: sending a preamble on an uplink bandwidth part BWP corresponding to the first downlink BWP. ### Claim 6 (depends on 4) The random access method according to claim 4, further comprising: when a random access attempt fails, sending the preamble on the active uplink BWP or on the uplink BWP corresponding to the first downlink BWP. ### Claim 7 (depends on 3) The random access method according to claim 3, wherein after the falling back to a first downlink BWP, the method further comprises: resetting at least one of a preamble transmission counter or a power ramping counter. ### Claim 8 (depends on 3) The random access method according to claim 3, wherein the falling back to a first downlink BWP comprises: falling back from contention free random access CFRA on the currently active downlink BWP to contention free random access CFRA on the first downlink BWP; or falling back from contention free random access CFRA on the currently active downlink BWP to contention based random access CBRA on the first downlink BWP. ### Claim 9 (depends on 1) The random access method according to claim 1, wherein the step of monitoring a random access response RAR in a random access process based on a configuration of a control resource set CORESET in the configuration information of the currently active downlink BWP or the configuration information of the serving cell comprises: when no control resource set CORESET or default control resource set CORESET corresponding to contention free random access CFRA is configured on the currently active downlink BWP or the serving cell, monitoring the RAR by falling back to a default CORESET 0 of a second downlink BWP; or when no control resource set CORESET or default CORESET corresponding to contention based random access CBRA is configured on the currently active downlink BWP or the serving cell, monitoring the RAR by falling back to a default CORESET 0 of a third downlink BWP; or when no control resource set CORESET or default control resource set CORESET corresponding to contention free random access CFRA is configured on the currently active downlink BWP or the serving cell, but a control resource set CORESET or default CORESET corresponding to contention based random access CBRA is configured on the currently active downlink BWP, monitoring the RAR by falling back to the control resource set CORESET or the default CORESET 0 of the CBRA on the currently active downlink BWP; or when no control resource set CORESET or default control resource set CORESET corresponding to contention based random access CBRA is configured on the currently active downlink BWP or the serving cell, but a control resource set CORESET or default CORESET corresponding to contention free random access CFRA is configured on the currently active downlink BWP, monitoring the RAR by falling back to the control resource set CORESET or the default CORESET 0 of the CFRA on the currently active downlink BWP, wherein the second downlink BWP or the third downlink BWP comprises: an initial downlink BWP, or a non-initial downlink BWP configured with a default CORESET, or a BWP configured with a control resource set CORESET or default CORESET corresponding to the CBRA or the CFRA. ### Claim 10 (depends on 1) The random access method according to claim 1, wherein before the step of monitoring a random access response RAR in a random access process based on a configuration of a control resource set CORESET in the configuration information of the currently active downlink BWP or the configuration information of the serving cell, the method comprises: when the currently active downlink BWP overlaps a fourth BWP, sending a random access preamble by using a public random access configuration broadcast on the fourth BWP or using resources of a public random access configuration configured by dedicated radio resource control RRC signaling, wherein the fourth BWP comprises: an initial downlink BWP, or a BWP overlapping the currently active downlink BWP. ### Claim 11 A terminal, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program, when executed by the processor, implements the steps in a random access method, the method comprising: receiving configuration information of a currently active downlink bandwidth part BWP or a serving cell; and monitoring a random access response RAR in a random access process based on a configuration of a control resource set CORESET in the configuration information of the currently active downlink BWP or the configuration information of the serving cell; wherein the step of monitoring a random access response RAR in a random access process based on a configuration of a control resource set CORESET in the configuration information of the currently active downlink BWP or the configuration information of the serving cell comprises: monitoring the random access response RAR in the random access process based on a configuration of a default CORESET 0 in a case that no CORESET is explicitly configured on the currently active downlink BWP or the serving cell. ### Claim 12 (depends on 11) The terminal according to claim 11, wherein in the random access method implemented by the computer program, the step of monitoring a random access response RAR in a random access process based on a configuration of a control resource set CORESET in the configuration information of the currently active downlink BWP or the configuration information of the serving cell comprises: when no CORESET is explicitly configured on the currently active downlink BWP or the serving cell, monitoring the random access response RAR in the random access process based on a configuration of a default CORESET 0; or when a CORESET is configured on the currently active downlink BWP or the serving cell, monitoring the random access response RAR in the random access process based on the configured CORESET. ### Claim 13 (depends on 12) The terminal according to claim 12, wherein in the random access method implemented by the computer program, the step of monitoring the random access response RAR in the random access process based on a configuration of a default CORESET 0 comprises: when the default CORESET 0 is configured on the currently active downlink BWP or the serving cell, monitoring the RAR in the random access process by directly falling back to the default CORESET 0 of the currently active downlink BWP or the serving cell. ### Claim 14 (depends on 12) The terminal according to claim 12, wherein in the random access method implemented by the computer program, the step of monitoring the random access response RAR in the random access process based on a configuration of a default CORESET 0 comprises: when the default CORESET 0 is not configured on the currently active downlink BWP or the serving cell, falling back to a first downlink BWP, and monitoring the RAR in the random access process on a default CORESET 0 on the first downlink BWP; or when the default CORESET 0 is configured on the currently active downlink BWP or the serving cell, falling back to a first downlink BWP, and monitoring the RAR in the random access process on a default CORESET 0 on the first downlink BWP, wherein the first downlink BWP comprises: an initial downlink BWP, or a non-initial downlink BWP configured with a default CORESET. ### Claim 15 (depends on 14) The terminal according to claim 14, wherein in the random access method implemented by the computer program, before the falling back to a first downlink BWP, the method further comprises: sending a preamble on a currently active uplink bandwidth part BWP. ### Claim 16 (depends on 14) The terminal according to claim 14, wherein in the random access method implemented by the computer program, after the falling back to a first downlink BWP, the method further comprises: sending a preamble on an uplink bandwidth part BWP corresponding to the first downlink BWP. ### Claim 17 (depends on 15) The terminal according to claim 15, wherein in the random access method implemented by the computer program, after the falling back to a first downlink BWP, the method further comprises: resetting at least one of a preamble transmission counter or a power ramping counter. ### Claim 18 A network device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program, when executed by the processor, implements the steps in a random access method, the method comprising: sending configuration information of a currently active downlink bandwidth part BWP or a serving cell to a terminal, wherein the configuration information of the currently active downlink BWP or the serving cell comprises a configuration of a control resource set CORESET; and sending a random access response RAR in a random access process to the terminal, to enable the terminal to monitor the random access response RAR in the random access process based on a configuration of a default CORESET 0 in a case that no CORESET is explicitly configured on the currently active downlink BWP or the serving cell.