# US 2024/0205776 A1 · Cell reselection method and apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2024/0205776 A1 - Document ID: US20240205776A1 - Status: Published application - Kind: A1 - Application number: 18/589,945 - Filed: 2024-02-28 - Published: 2024-06-20 - Earliest claimed: 2021-08-31 - Assignees: Huawei Technologies Co., Ltd. - Applicants: Huawei Technologies Co., Ltd. - Inventors: Wuyang ZHENG; Tingting GENG - Web page: https://patentgrep.com/patent/US20240205776A1 ## CPC - H04W 36/24: Reselection being triggered by specific parameters - H04W 12/009: {specially adapted for networks, e.g. wireless sensor networks, ad-hoc networks, RFID networks or cloud networks} - H04W 12/122: Counter-measures against attacks; Protection against rogue devices - H04W 36/0055: {Transmission or use of information for re-establishing the radio link} - H04W 36/08: Reselecting an access point - H04W 48/02: Access restriction performed under specific conditions - H04W 76/18: Management of setup rejection or failure - H04W 36/083: {wherein at least one of the access points is a moving node} - H04W 48/20: Selecting an access point - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract This application provides a cell reselection method and an apparatus. The method includes: A terminal device sends a radio resource control RRC setup request message to a first radio access network device a plurality of times. The terminal device receives a response message for the RRC setup request message within a preset time. The terminal device determines, based on a first preset threshold and a quantity of consecutive times that the response message is not received, whether to perform cell reselection, or the terminal device determines, based on a third preset threshold and a quantity of times that the RRC setup request message is sent or a quantity of times that the response message for the RRC setup request message is received, whether to trigger a cell reselection mechanism. ## Claims ### Claim 1 A cell reselection method, comprising: sending a radio resource control RRC setup request message to a first radio access network device a plurality of times; determining based on a first preset threshold and a quantity of consecutive times that a response message is not received, whether to perform cell reselection, or determining, based on a third preset threshold and a quantity of times that the RRC setup request message is sent or a quantity of times that the response message is received, whether to perform cell reselection, wherein the response message is for the RRC setup request message within a preset time, the first preset threshold is received from a second radio access network device and stored, and the second radio access network device is a radio access network device accessed by a terminal device before the terminal device accesses the first radio access network device. ### Claim 2 (depends on 1) The method according to claim 1, wherein second configuration information is not received from the first radio access network device, and the second configuration information is used to determine whether to perform cell reselection. ### Claim 3 (depends on 1) The method according to claim 1, wherein the determining based on a first preset threshold and a quantity of consecutive times that the response message is not received, whether to perform cell reselection comprises: if the quantity of consecutive times that the response message is not received is greater than or equal to the first preset threshold, determining depending on whether a first cell controlled by the first radio access network device fulfills a first criterion, whether to perform cell reselection; or if the quantity of consecutive times that the response message is not received is less than the first preset threshold, determining not to perform cell reselection. ### Claim 4 (depends on 3) The method according to claim 3, wherein the determining depending on whether a first cell controlled by the first radio access network device fulfills a first criterion, whether to perform cell reselection comprises: determining based on first configuration information, whether the first cell fulfills the first criterion, wherein the first configuration information is received from the second radio access network device and stored, and the first configuration information comprises a first offset and a validity period of the first offset; if the first cell fulfills the first criterion, decreasing a priority of the first cell and/or increasing the first offset; and when the priority of the first cell is lower than a second preset threshold and/or the first cell does not fulfill the first criterion, determining to perform cell reselection. ### Claim 5 (depends on 4) The method according to claim 4, wherein the first criterion comprises an S criterion, and the first offset is an offset temporarily applied in the S criterion. ### Claim 6 (depends on 1) The method according to claim 1, wherein the determining based on a first preset threshold and a quantity of consecutive times that the response message is not received, whether to perform cell reselection comprises: if the quantity of consecutive times that the response message is not received is greater than or equal to the first preset threshold, determining to perform cell reselection; or if the quantity of consecutive times that the response message is not received is less than the first preset threshold, determining not to perform cell reselection. ### Claim 7 (depends on 1) The method according to claim 1, wherein the third preset threshold is predefined in a protocol, or the third preset threshold is determined by the terminal device, or the third preset threshold is received from the first radio access network device or the second radio access network device. ### Claim 8 (depends on 1) The method according to claim 1, wherein the determining based on a third preset threshold and a quantity of times that the RRC setup request message is sent or a quantity of times that the response message is received, whether to perform cell reselection comprises: if the quantity of times that the RRC setup request message is sent or the quantity of times that the response message is received is greater than or equal to the third preset threshold, determining depending on whether a first cell controlled by the first radio access network device fulfills a first criterion, whether to perform cell reselection; or if the quantity of times that the RRC setup request message is sent or the quantity of times that the response message is received is less than the third preset threshold, determining not to perform cell reselection. ### Claim 9 (depends on 8) The method according to claim 8, wherein the determining depending on whether a first cell controlled by the first radio access network device fulfills a first criterion, whether to perform cell reselection comprises: determining based on second configuration information, whether the first cell fulfills the first criterion, wherein the second configuration information is received from the first radio access network device, and the second configuration information comprises a second offset and a validity period of the second offset; if the first cell fulfills the first criterion, decreasing a priority of the first cell and/or increasing the second offset; and when the priority of the first cell is lower than the second preset threshold and/or the first cell does not fulfill the first criterion, determining to perform cell reselection. ### Claim 10 (depends on 9) The method according to claim 9, wherein the first criterion comprises an S criterion, and the second offset is an offset temporarily applied in the S criterion. ### Claim 11 (depends on 1) The method according to claim 1, wherein the determining based on a third preset threshold and a quantity of times that the RRC setup request message is sent or a quantity of times that the response message is received, whether to perform cell reselection comprises: if the quantity of times that the RRC setup request message is sent or the quantity of times that the response message is received is greater than or equal to the third preset threshold, determining to perform cell reselection; or if the quantity of times that the RRC setup request message is sent or the quantity of times that the response message is received is less than the third preset threshold, determining not to perform cell reselection. ### Claim 12 (depends on 3) The method according to claim 3, wherein the method further comprises: excluding the first cell from a candidate cell in a process of performing cell reselection. ### Claim 13 (depends on 6) The method according to claim 6, wherein the response message comprises an RRC setup message and/or an RRC reject message. ### Claim 14 A communication apparatus, comprising at least one circuitry configured to: send a radio resource control RRC setup request message to a first radio access network device a plurality of times, wherein determine, based on a first preset threshold and a quantity of consecutive times that the response message is not received, whether to perform cell reselection, or determine, based on a third preset threshold and a quantity of times that the RRC setup request message is sent or a quantity of times that the response message is received, whether to perform cell reselection, wherein the response message is for the RRC setup request message within a preset time, the first preset threshold is received from a second radio access network device and stored, and the second radio access network device is a radio access network device accessed by a terminal device before the terminal device accesses the first radio access network device. ### Claim 15 (depends on 14) The apparatus according to claim 14, wherein second configuration information is received from the first radio access network device, and the second configuration information is used to determine whether to perform cell reselection. ### Claim 16 (depends on 14) The apparatus according to claim 14, wherein the apparatus is further configured to: if the quantity of consecutive times that the response message is not received is greater than or equal to the first preset threshold, determine, depending on whether a first cell controlled by the first radio access network device fulfills a first criterion, whether to perform cell reselection; or if the quantity of consecutive times that the response message is not received is less than the first preset threshold, determine not to perform cell reselection. ### Claim 17 (depends on 16) The apparatus according to claim 16, wherein the apparatus is further configured to: determine, based on first configuration information, whether the first cell fulfills the first criterion, wherein the first configuration information is received from the second radio access network device and stored, and the first configuration information comprises a first offset and a validity period of the first offset; if the first cell fulfills the first criterion, decrease a priority of the first cell and/or increase the first offset; and when the priority of the first cell is lower than a second preset threshold and/or the first cell does not fulfill the first criterion, the determine to perform cell reselection. ### Claim 18 (depends on 17) The apparatus according to claim 17, wherein the first criterion comprises an S criterion, and the first offset is an offset temporarily applied in the S criterion. ### Claim 19 (depends on 14) The apparatus according to claim 14, wherein the apparatus is further configured to: if the quantity of consecutive times that the response message is not received is greater than or equal to the first preset threshold, determine to perform cell reselection; or if the quantity of consecutive times that the response message is not received is less than the first preset threshold, determine not to perform cell reselection. ### Claim 20 (depends on 16) The apparatus according to claim 16, wherein the apparatus is further configured to exclude the first cell from a candidate cell in a process of performing cell reselection.