Patent ID: 6356207
Filing Date: 2002-03-12
Classification: H04B

Abstract:
A DSRC car-mounted equipment comprising:a transmission/reception antenna for executing communication with an on-the-road equipment installed on a road; a transmission/reception change-over switch for changing over the transmission/reception function of said transmission/reception antenna; a transmission/reception circuit including a reception circuit and a transmission circuit selectively connected to said transmission/reception antenna via said transmission/reception change-over switch; a first local oscillator for generating a car-mounted equipment frequency related to said transmission/reception circuit; a demodulator for detecting the electric field intensity and for picking up reception data from a signal received by said reception circuit; a car-mounted controller for fetching said reception data by controlling the change-over of said transmission/reception change-over switch, and for sending transmission data to said transmission circuit; an information output means connected to said car-mounted controller; and a second local oscillator that outputs, to said transmission circuit, a frequency for detecting abnormal condition corresponding to an on-the-road equipment frequency transmitted from said on-the-road equipment; wherein said car-mounted controller includes an abnormal circuit judging means for judging the condition of said transmission/reception circuit by using said frequency for detecting abnormal condition; and said abnormal circuit judging means judges said transmission/reception circuit to be abnormal and drives said information output means when at least either the electric field intensity or the reception data detected based upon a leakage power of said frequency for detecting abnormal condition is not satisfying a predetermined condition in a state where said transmission/reception change-over switch is connected to said reception circuit.