Patent ID: 7835396
Filing Date: 2010-11-16
Classification: H04L

Abstract:
1. A communication apparatus mounted in each vehicle and communicable with other communication apparatuses mounted in other vehicles respectively, comprising: communication means configured to communicate with the communication apparatuses mounted in the other vehicles by wireless communication; communication controlling means configured to control the communication means to enable the communication means to send out at least one packet including information to the other communication apparatuses, and to receive packets including information sent out from the other communication apparatuses; vehicle speed detecting means configured to detect a speed at which a vehicle concerned runs; communication controlling means configured to control the communication means to send out packets, the communication controlling means including means for (i) shortening a transmission interval for sending packets as an increase in the speed of the vehicle detected by the vehicle speed detecting means, (ii) adding information indicative of a transmission interval into the packets being sent out, and (iii) controlling the communication means to send out the packets at the transmission interval to the other communication apparatuses; approach conditions determining means configured to determine that a vehicle in the other vehicles is approaching to the vehicle concerned from behind thereof, when the transmission interval of the packets transmitted from the behind-approaching vehicle is shorter than that of the vehicle concerned; and resetting means configured to reset the transmission interval so that the transmission interval is shortened, when the approach conditions determining means determines that the behind-approaching vehicle is approaching to the vehicle concerned.