# US 2021/0243707 A1 · Communication apparatus and communication system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0243707 A1 - Document ID: US20210243707A1 - Status: Published application - Kind: A1 - Application number: 17/269,044 - Filed: 2019-07-23 - Published: 2021-08-05 - Earliest claimed: 2018-09-13 - Assignees: Sony Semiconductor Solutions Corporation - Applicants: Sony Semiconductor Solutions Corporation - Inventors: Michito Ishii - Web page: https://patentgrep.com/patent/US20210243707A1 ## CPC - G04G 7/00: Synchronisation (radio-controlled time-pieces G04R) - H04W 56/001: {Synchronization between nodes} - G04R 20/26: the radio signal being a near-field communication signal - G04R 40/00: Correcting the clock frequency - H04J 3/0658: {Clock or time synchronisation among packet nodes} - G04G: ELECTRONIC TIME-PIECES - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - G04R: RADIO-CONTROLLED TIME-PIECES - H04J: MULTIPLEX COMMUNICATION (transmission in general H04B; peculiar to transmission of digital information H04L5/00; systems for the simultaneous or sequential transmission of more than one television signal H04N7/08; in exchanges H04Q11/00; stereophonic systems H04S) ## Abstract Plural communication apparatuses connected via communication are synchronized while flexibly coping with a change in the communication state. A clock time management section manages a clock time. A clock time measurement section measures a clock time of another clock time management section of another apparatus and a clock time of the clock time management section of this apparatus for every predetermined processing, in the course of communication with the other apparatus having the other clock time management section. A clock time difference generation section generates a clock time difference between the clock time of the other clock time management section and the clock time of the clock time management section on the basis of the measured clock times. A clock time correction instruction section instructs the other apparatus to correct the clock time of the other clock time management section on the basis of the generated clock time difference. ## Claims ### Claim 1 A communication apparatus comprising: a clock time management section that manages a clock time; a clock time measurement section that measures a clock time of another clock time management section of another apparatus and a clock time of the clock time management section for every predetermined processing, in a course of communication with the other apparatus having the other clock time management section; a clock time difference generation section that generates a clock time difference between the clock time of the other clock time management section and the clock time of the clock time management section on a basis of the measured clock times; and a clock time correction instruction section that instructs the other apparatus to correct the clock time of the other clock time management section on a basis of the generated clock time difference. ### Claim 2 (depends on 1) The communication apparatus according to claim 1, wherein the clock time measurement section transmits and receives a clock time measurement packet that stores the clock time of the other clock time management section and the clock time of the clock time management section acquired for every predetermined processing. ### Claim 3 (depends on 1) The communication apparatus according to claim 1, wherein the clock time measurement section performs, as the predetermined processing, measuring of a clock time at which transmission to the other apparatus is performed and clock times at which transmission and reception by the other apparatus are performed. ### Claim 4 (depends on 1) The communication apparatus according to claim 1, wherein the clock time measurement section performs, as the predetermined processing, measuring of a clock time of processing that is performed before transmission to the other apparatus is performed and a clock time of internal processing that is performed after reception by the other apparatus is performed. ### Claim 5 (depends on 1) The communication apparatus according to claim 1, wherein the clock time correction instruction section transmits, to the other apparatus, a clock time setting packet for setting the clock time of the other clock time management section to a designated clock time. ### Claim 6 (depends on 1) The communication apparatus according to claim 1, wherein the clock time correction instruction section sets, as delay time, time required for processing that is performed before transmission to the other apparatus is performed, the communication with the other apparatus, and internal processing that is performed after reception by the other apparatus is performed, and has a clock time obtained by reflecting the delay time in the clock time of the clock time management section set as the clock time of the other clock time management section. ### Claim 7 (depends on 1) The communication apparatus according to claim 1, further comprising: an output section that performs predetermined output according to the clock time of the clock time management section. ### Claim 8 (depends on 1) The communication apparatus according to claim 1, wherein the communication is held by a communication scheme that permits intermittent connection. ### Claim 9 (depends on 8) The communication apparatus according to claim 8, wherein the communication is held in compliance with a wireless communication standard Bluetooth (registered trademark) Low Energy, the clock time measurement section transmits and receives a packet for measuring the clock time of the other clock time management section and the clock time of the clock time management section by GATT (Generic ATTribute profile) connection, and the clock time correction instruction section transmits a packet for giving an instruction on correction of the clock time of the other clock time management section by the GATT connection. ### Claim 10 A communication apparatus comprising: a clock time management section that manages a clock time; a clock time measurement section that measures a clock time of another clock time management section of another apparatus and a clock time of the clock time management section for every predetermined processing, in a course of communication with the other apparatus having the other clock time management section; a clock time difference generation section that generates a clock time difference between the clock time of the other clock time management section and the clock time of the clock time management section on a basis of the measured clock times; and a clock time correction section that corrects the clock time of the clock time management section on a basis of the generated clock time difference. ### Claim 11 A communication system comprising: first and second communication apparatuses each including a clock time management section that manages a clock time, wherein the first communication apparatus includes a clock time measurement section that measures a clock time of the clock time management section of the second communication apparatus and a clock time of the clock time management section of the first communication apparatus for every predetermined processing, in a course of communication with the second communication apparatus, a clock time difference generation section that generates a clock time difference between the clock time of the clock time management section of the second communication apparatus and the clock time of the clock time management section of the first communication apparatus on a basis of the measured clock times, and a clock time correction instruction section that instructs the other apparatus to correct the clock time of the clock time management section of the second communication apparatus on a basis of the generated clock time difference, and the second communication apparatus corrects the clock time of the clock time management section of the second communication apparatus according to the instruction from the clock time correction instruction section of the first communication apparatus.