| CPC B60R 25/24 (2013.01) [G07C 9/00309 (2013.01); H04B 17/318 (2015.01); G07C 2009/00793 (2013.01); G07C 2209/63 (2013.01)] | 11 Claims |
|
1. A communication device mounted on a mobile object, the communication device comprising:
an acquisition unit configured to acquire a ranging trigger signal for starting measurement of a distance between the communication device and a portable device carried by a person; and
a communication control unit configured not to start ranging communication for measurement of the distance based on a fact that first specific information defined in advance and necessary for determination of the mobile object does not match second specific information included in the acquired ranging trigger signal and necessary for determination of the mobile object,
wherein the communication device is mounted in a first mobile object,
wherein the acquisition unit acquires a first ranging trigger signal for starting measurement of a first distance between the communication device and a first portable device,
wherein the communication control unit does not start first ranging communication for measurement of the first distance based on a fact that first specific information necessary for determination of the first mobile object does not match second specific information included in the first ranging trigger signal and necessary for determination of a second mobile object,
wherein the communication control unit does not start the first ranging communication and maintains a reception waiting state of a ranging trigger signal based on the fact that the first specific information does not match the second specific information included in the first ranging trigger signal,
wherein the communication control unit starts second ranging communication for measurement of a second distance between the communication device and a second portable device based on a fact that the first specific information is included in a second ranging trigger signal acquired from the second portable device in the reception waiting state,
wherein the acquisition unit acquires, from the second ranging trigger signal, counter information that indicates a past number of times a ranging trigger signal has been transmitted from the second portable device to the communication device, and
wherein the communication control unit outputs the counter information associated with a result of the second ranging communication to a control device.
|