Patent attributes
A tire air pressure detection system having a transmitter provided at each of a plurality of wheels provided with tires and sending out a detection signal corresponding to the air pressure of the tire attached to the corresponding wheel and a receiver provided at the chassis side and provided with first antennas arranged near the transmitters of the plurality of wheels and a first controller receiving detection signals through the first antennas and finding the air pressures of the tires provided at the plurality of wheels based on the detection signals, wherein the receiver is designed so that the first controller measures the strength of each the detection signal, sets a power control signal in accordance with that strength, then sends the power control signal to the transmitter originating the detection signal, and each transmitter is provided with a second antenna receiving its corresponding power control signal and a second controller controlling a transmission power for sending the detection signal based on the received power control signal.
