# US 12,225,416 B2 · Communication 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 12,225,416 B2 - Document ID: US12225416B2 - Status: Granted - Kind: B2 - Application number: 17/652,540 - Filed: 2022-02-25 - Published: 2022-06-09 - Granted: 2025-02-11 - Earliest claimed: 2019-08-30 - Assignees: Huawei Technologies Co., Ltd. - Applicants: Huawei Technologies Co., Ltd. - Inventors: Lei Chen; Bingzhao Li; Xun Tang; Hong Wang - Web page: https://patentgrep.com/patent/US12225416B2 ## CPC - H04W 36/0016: {Hand-off preparation specially adapted for end-to-end data sessions} - H04W 36/08: Reselecting an access point - H04W 36/324: {by mobility data, e.g. speed data} - H04W 36/0085: {Hand-off measurements} - H04W 36/36: by user or terminal equipment - H04W 84/06: Airborne or Satellite Networks (space-based or airborne stations H04B7/185) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract A first network device determines a first cell. The first network device sends a first message, where the first message includes an identifier of the first cell, and the identifier of the first cell is used to indicate a terminal device to perform cell reestablishment. ## Claims ### Claim 1 A method, comprising: determining, by a first network device, a first cell; sending, by the first network device, a first message, wherein the first message comprises an identifier of the first cell, and the identifier of the first cell indicates to a terminal device to perform cell reestablishment of the terminal device in the first cell; and receiving, by the first network device, a reestablishment request message from the terminal device, wherein the reestablishment request message is used to request to perform cell reestablishment of the terminal device in the first cell, wherein the reestablishment request message comprises a cause value that is used to indicate that the cell reestablishment to be performed in the first cell is to be performed based on the first message. ### Claim 2 (depends on 1) The method according to claim 1, wherein the first message is sent in a broadcast manner. ### Claim 3 (depends on 1) The method according to claim 1, wherein the first message further comprises a first condition, wherein the first condition indicates to the terminal device to perform cell reestablishment when the first condition is met, and wherein the first condition comprises that: the first message is received by the terminal device. ### Claim 4 (depends on 1) The method according to claim 1, wherein the first message further comprises a first condition, wherein the first condition indicates to the terminal device to perform cell reestablishment when the first condition is met, and wherein the first condition comprises that the terminal device is located in a first location. ### Claim 5 (depends on 1) The method according to claim 1, wherein the first message further comprises a first condition, wherein the first condition indicates to the terminal device to perform cell reestablishment when the first condition is met, and wherein the first condition comprises that a reference signal received power of the first cell is greater than a first threshold. ### Claim 6 (depends on 1) The method according to claim 1, further comprising: sending, by the first network device, context information of the terminal device to a second network device, wherein the context information is used by the second network device to establish a connection to the terminal device, and the first cell is a cell served by the second network device. ### Claim 7 (depends on 1) The method according to claim 1, wherein the first network device is deployed on a satellite. ### Claim 8 (depends on 1) The method of claim 1, wherein performing the cell reestablishment of the terminal device in the first cell comprises the terminal device establishing a connection to the first cell for the first time. ### Claim 9 (depends on 1) The method of claim 1, wherein performing the cell reestablishment of the terminal device in the first cell comprises the terminal device establishing a connection to the first cell after a cell handover failure. ### Claim 10 An apparatus, comprising: at least one processor; and a non-transitory computer readable storage medium storing a program that is executable by the at least one processor; the program including instructions to: receive a first message from a first network device, wherein the first message carries an identifier of a first cell, send a reestablishment request message in the first cell based on the identifier of the first cell, wherein the reestablishment request message is used to request to perform cell reestablishment of the apparatus in the first cell, and send a second message to a second network device, wherein the second message is used to request to perform reestablishment in the first cell, the second message comprises a cause value, and the cause value is used to indicate that cell reestablishment to be performed in the first cell is to be performed based on the first message. ### Claim 11 (depends on 10) The apparatus according to claim 10, wherein the first message comprises a first condition that indicates to the apparatus to send the reestablishment request message in the first cell when the first condition is met, wherein the first condition comprises one or more of or any combination of the following: the first message is received by the apparatus; the apparatus is located in a first location; or a reference signal received power of the first cell is greater than a first threshold. ### Claim 12 (depends on 10) The apparatus according to claim 10, wherein performing the cell reestablishment of the apparatus in the first cell includes the apparatus establishing a connection to the first cell for the first time, or the apparatus establishing a connection to the first cell after a cell handover failure. ### Claim 13 An apparatus, comprising: at least one processor; and a non-transitory computer readable storage medium storing a program executable by the at least one processor, the program including instructions to: determine a first cell, send a first message, wherein the first message comprises an identifier of the first cell, and the identifier of the first cell indicates to a terminal device to perform cell reestablishment of the terminal device in the first cell, and receive a reestablishment request message from the terminal device, wherein the reestablishment request message is used to request to perform cell reestablishment of the terminal device in the first cell, wherein the reestablishment request message comprises a cause value that is used to indicate that the cell reestablishment to be performed in the first cell is to be performed based on the first message. ### Claim 14 (depends on 13) The apparatus according to claim 13, wherein the program includes instructions to send the first message in a broadcast manner. ### Claim 15 (depends on 13) The apparatus according to claim 13, wherein the first message further comprises a first condition, wherein the first condition indicates to the terminal device to perform cell reestablishment when the first condition is met, and wherein the first condition comprises that the first message is received by the terminal device. ### Claim 16 (depends on 13) The apparatus according to claim 13, wherein the first message further comprises a first condition, wherein the first condition indicates to the terminal device to perform cell reestablishment when the first condition is met, and wherein the first condition comprises that the terminal device is located in a first location. ### Claim 17 (depends on 13) The apparatus according to claim 13, wherein the first message further comprises a first condition, wherein the first condition indicates to the terminal device to perform cell reestablishment when the first condition is met, and wherein the first condition comprises that a reference signal received power of the first cell is greater than a first threshold. ### Claim 18 (depends on 13) The apparatus according to claim 13, wherein the program further includes instructions to: send context information of the terminal device to a second network device, wherein the context information is used by the second network device to establish a connection to the terminal device, and the first cell is a cell served by the second network device. ### Claim 19 (depends on 13) The apparatus according to claim 13, wherein the apparatus is deployed on a satellite. ### Claim 20 (depends on 13) The apparatus according to claim 13, wherein performing the cell reestablishment of the terminal device in the first cell comprises a terminal device establishing a connection to the first cell for the first time, or the terminal device establishing a connection to the first cell after a cell handover failure.