# US 8,788,190 B2 · On-vehicle wireless communication apparatus and communication system thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,788,190 B2 - Document ID: US8788190B2 - Status: Granted - Kind: B2 - Application number: 13/489,906 - Filed: 2012-06-06 - Published: 2012-12-20 - Granted: 2014-07-22 - Earliest claimed: 2011-06-15 - Assignees: Denso Corporation - Applicants: Junichirou Funabashi - Inventors: Junichirou Funabashi - Web page: https://patentgrep.com/patent/US8788190B2 ## CPC - G08G 1/0112: {from the vehicle, e.g. floating car data [FCD]} - G01S 7/282: Transmitters - G01S 7/285: Receivers - G08G 1/0967: Systems involving transmission of highway information, e.g. weather, speed limits (transmission of navigation instructions to the vehicle G08G1/0968) - G08G: TRAFFIC CONTROL SYSTEMS (guiding railway traffic, ensuring the safety of railway traffic B61L; arrangement of road signs or traffic signals E01F9/00; radar or analogous systems, sonar systems, lidar systems specially adapted for traffic control G01S13/91, G01S15/88, G01S17/88; {radar or analogous systems, sonar systems, lidar systems specially adapted for anti-collision purposes G01S13/93, G01S15/93, G01S17/93}) - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES ## Abstract An on-vehicle wireless communication apparatus for transmitting transmission data having positional information wirelessly at a frequency includes: a receiver receiving the transmission data from another apparatus; a positional information acquiring unit acquiring the positional information; a location specifying unit specifying a location relationship between a vehicle and another vehicle based on the positional information of the vehicle and the another vehicle; an another-apparatus transmission timing specifying unit specifying a transmission timing of the another apparatus when the another vehicle is located immediately in front of the vehicle; and a transmission timing adjusting unit adjusting a transmission timing of the apparatus so that the transmission data is transmitted at the frequency with an adjusted transmission timing, which is later by a predetermined time than the transmission timing of the another apparatus. ## Claims ### Claim 1 An on-vehicle wireless communication apparatus mounted on a vehicle for transmitting transmission data wirelessly at a predetermined frequency, the transmission data including at least positional information of the vehicle, the apparatus comprising: a receiver that sequentially receives the transmission data transmitted from another on-vehicle wireless communication apparatus mounted on another vehicle; a positional information acquiring unit that sequentially acquires the positional information of the vehicle; a location specifying unit that specifies a location relationship between the vehicle and the another vehicle based on the positional information of the vehicle acquired by the positional information acquiring unit and the positional information of the another vehicle received by the receiver; an another-apparatus transmission timing specifying unit that specifies a transmission timing of the transmission data in the another on-vehicle wireless communication apparatus when the another vehicle is located immediately in front of the vehicle; and a transmission timing adjusting unit that adjusts a transmission timing of the transmission data to be transmitted from the on-vehicle wireless communication apparatus so that the transmission data is transmitted at the predetermined frequency with an adjusted transmission timing of the on-vehicle wireless communication apparatus, which is later by a predetermined time than the transmission timing of the another on-vehicle wireless communication apparatus; wherein the transmission timing adjusting unit temporarily changes the predetermined frequency of the transmission data in the on-vehicle wireless communication apparatus to adjust the transmission timing of the on-vehicle wireless communication apparatus so that the transmission timing of the on-vehicle wireless communication apparatus step-wisely comes closer to the adjusted transmission timing of the on-vehicle wireless communication apparatus every time the transmission data is transmitted. ### Claim 2 (depends on 1) The on-vehicle wireless communication apparatus according to claim 1, wherein a lower limit of the predetermined frequency is defined when the transmission timing adjusting unit temporarily changes the predetermined frequency, and wherein the transmission timing adjusting unit adjusts the transmission timing of the on-vehicle wireless communication apparatus so as not to fall below the lower limit when the transmission timing adjusting unit temporarily changes the predetermined frequency. ### Claim 3 (depends on 1) The on-vehicle wireless communication apparatus according to claim 1, wherein the transmission timing adjusting unit does not adjust the transmission timing of the on-vehicle wireless communication apparatus when the another vehicle is not located immediately in front of the vehicle. ### Claim 4 (depends on 1) A communication system comprising a plurality of on-vehicle wireless communication apparatuses, wherein each on-vehicle wireless communication apparatus is defined according to claim 1, and wherein each on-vehicle wireless communication apparatus is mounted on a respective vehicle. ### Claim 5 An on-vehicle wireless communication apparatus mounted on a vehicle for transmitting transmission data wirelessly at a predetermined frequency, the transmission data including at least positional information of the vehicle, the apparatus comprising: a receiver that sequentially receives the transmission data transmitted from another on-vehicle wireless communication apparatus mounted on another vehicle; a positional information acquiring unit that sequentially acquires the positional information of the vehicle; a location specifying unit that specifies a location relationship between the vehicle and the another vehicle based on the positional information of the vehicle acquired by the positional information acquiring unit and the positional information of the another vehicle received by the receiver; an another-apparatus transmission timing specifying unit that specifies a transmission timing of the transmission data in the another on-vehicle wireless communication apparatus when the another vehicle is located immediately in front of the vehicle; and a transmission timing adjusting unit that adjusts a transmission timing of the transmission data to be transmitted from the on-vehicle wireless communication apparatus so that the transmission data is transmitted at the predetermined frequency with an adjusted transmission timing of the on-vehicle wireless communication apparatus, which is later by a predetermined time than the transmission timing of the another on-vehicle wireless communication apparatus; wherein the transmission data further includes at least travel direction information of the vehicle in addition to the positional information of the vehicle, the on-vehicle wireless communication apparatus further comprising: a travel direction information acquiring unit that sequentially acquires the travel direction information of the vehicle, wherein the location specifying unit specifies the location relationship between the vehicle and the another vehicle disposed in a travel direction of the vehicle based on the positional information of the vehicle, the travel direction information of the vehicle acquired by the travel direction information acquiring unit, and the positional information and the travel direction information of the another vehicle received by the receiver, and wherein the other-apparatus transmission timing specifying unit specifies the transmission timing of the another on-vehicle wireless communication apparatus when the another vehicle having a travel direction equal to the travel direction of the vehicle is located immediately in front of the vehicle. ### Claim 6 (depends on 5) The on-vehicle wireless communication apparatus according to claim 5, wherein the transmission data to be transmitted from the on-vehicle wireless communication apparatus further includes the transmission data of the another on-vehicle wireless communication apparatus received by the receiver. ### Claim 7 (depends on 6) The on-vehicle wireless communication apparatus according to claim 6 further comprising: an important information acquiring unit that acquires important information, which affects a travel condition of other vehicles disposed around the vehicle, wherein, when the important information acquiring unit acquires the important information, the transmission data to be transmitted from the on-vehicle wireless communication apparatus further includes the important information of the vehicle, and wherein, when the another vehicle having the travel direction equal to the travel direction of the vehicle is located immediately in front of the vehicle, and the transmission data of the another on-vehicle wireless communication apparatus includes important information, the transmission data to be transmitted from the on-vehicle wireless communication apparatus further includes the important information of the another on-vehicle wireless communication apparatus. ### Claim 8 (depends on 7) The on-vehicle wireless communication apparatus according to claim 7, wherein the location specifying unit specifies, in the location relationship between the vehicle and the another vehicle disposed in the travel direction of the vehicle, whether the vehicle and the another vehicle are located on a same track, and wherein, when the another vehicle having the travel direction equal to the travel direction of the vehicle is located immediately in front of the vehicle on the same track, and the transmission data of the another on-vehicle wireless communication apparatus includes important information, the transmission data to be transmitted from the on-vehicle wireless communication apparatus further includes the important information of the another on-vehicle wireless communication apparatus. ### Claim 9 (depends on 7) The on-vehicle wireless communication apparatus according to claim 7, wherein the location specifying unit specifies, in the location relationship between the vehicle and the another vehicle disposed in the travel direction of the vehicle, whether the vehicle and the another vehicle are located on a same track, and wherein, when the another vehicle having the travel direction equal to the travel direction of the vehicle is located immediately in front of the vehicle on a track different from a track of the vehicle, and the transmission data of the another on-vehicle wireless communication apparatus includes important information, the transmission data to be transmitted from the on-vehicle wireless communication apparatus further includes the important information of the another on-vehicle wireless communication apparatus. ### Claim 10 (depends on 6) The on-vehicle wireless communication apparatus according to claim 6 further comprising: an important information acquiring unit that acquires important information, which affects a travel condition of other vehicles disposed around the vehicle, wherein, when the important information acquiring unit acquires the important information, the transmission data to be transmitted from the on-vehicle wireless communication apparatus further includes the important information, wherein the important information has a level, which defines an importance degree, wherein, when the importance degree of the important information received from the another on-vehicle wireless communication apparatus is lower than a predetermined importance degree, the transmission data to be transmitted from the on-vehicle wireless communication apparatus further includes the important information of the another on-vehicle wireless communication apparatus mounted in the another vehicle, which has the travel direction equal to the travel direction of the vehicle and is located in front of the vehicle, and wherein, when the importance degree of the important information received from the another on-vehicle wireless communication apparatus is equal to or higher than the predetermined importance degree, the transmission data to be transmitted from the on-vehicle wireless communication apparatus further includes the important information of the another on-vehicle wireless communication apparatus mounted in the another vehicle, which is located in front of the vehicle. ### Claim 11 (depends on 7) The on-vehicle wireless communication apparatus according to claim 7, wherein the important information includes at least one of information related to a change in behavior of the vehicle, actuation information of a device that is actuated upon detecting contact between the vehicle and an obstacle, and actuation information of a device that is actuated upon detecting a dangerousness of contact between the vehicle and the obstacle. ### Claim 12 (depends on 7) The on-vehicle wireless communication apparatus according to claim 7, wherein, when the transmission data including the important information is transmitted, the important information includes transfer stop condition information that specifies a condition for stopping transfer of the important information. ### Claim 13 (depends on 12) The on-vehicle wireless communication apparatus according to claim 12, wherein the transfer stop condition information specifies a transfer frequency as the condition for stopping the transfer of the important information. ### Claim 14 (depends on 12) The on-vehicle wireless communication apparatus according to claim 12, wherein the transfer stop condition information specifies a distance from a transmission original position, at which an on-vehicle wireless communication apparatus initially transmits the important information, to a current position of the vehicle as the condition for stopping the transfer of the important information. ### Claim 15 (depends on 7) The on-vehicle wireless communication apparatus according to claim 7, wherein, when the transmission data including the important information is transmitted, the transmission data further includes source information that defines a transmission source vehicle of the important information, the on-vehicle wireless communication apparatus further comprising: a transferred information storage unit that stores the source information of the important information when the important information has been transferred; and a transfer determining unit that determines whether the important information has been already transferred, based on the source information in the transmission data received by the receiver and the source information stored in the transferred information storage unit when the transmission data received by the receiver includes the important information, and wherein, when the transfer determining unit determines that the important information has been already transferred, the important information is not transferred.