Patent ID: 6959177

Claim:
A DSRC car-mounted equipment for transmitting and receiving data with an on-the-road equipment comprising: a reception sensitivity-increasing means for increasing the reception sensitivity in a communication area with an on-the-road equipment in response to the entrance into a communication start area with the on-the-road equipment; wherein the reception sensitivity-increasing means returns the reception sensitivity back to a normal reception sensitivity of before entering into the communication start area in response to the end of communication with the on-the-road equipment, said DSRC car-mounted equipment further comprising: a local oscillator related to a reception mixer and a transmission modulator for transmission and reception to and from the on-the-road equipment; and a transmission output-increasing means for increasing the transmission output to the on-the-road equipment in the communication area in response to the entrance into the communication start area; wherein the transmission output-increasing means returns the transmission output to the normal transmission output of before the entrance into the communication start area in response to a end of communication with the on-the-road equipment; the reception sensitivity-increasing means and the transmission output-increasing means are constituted by an amplifier for amplifying a signal output from the local oscillator and a control unit for controlling the amplification factor of the amplifier in response to a signal received from the on-the-road equipment; and the control unit changes the amplification factor of the amplifier into an amplification factor larger than a normal amplification factor in response to at least a second or a subsequent communication signal received from the on-the-road equipment after the entrance into the communication start area.