Patent ID: 8193927

Claim:
A detection system for a vehicle having tire wheels and a chassis, the system comprising: a plurality of transceiver devices, each of which is attached to a corresponding one of the wheels and includes a receiver, a first controller and a transmitter, the receiver being configured to receive a detection trigger signal, the first controller being configured to detect a signal magnitude of the detection trigger signal received by the receiver and store signal magnitude data indicative of detected signal magnitude in a frame, and the transmitter being configured to transmit the frame; a trigger device attached to the chassis at a position, which is different in distance from the wheels, and configured to transmit the detection trigger signal; and a receiver device attached to the chassis and including a receiver and a second controller, the receiver being configured to output a detection trigger command signal for transmission of the detection trigger signal by the trigger device and to receive the frame from the transceiver device, the second controller being configured to detect a wheel attached with the transceiver device based on the signal magnitude data included in the frame, wherein the receiver device is configured to cause the trigger device to transmit a notification trigger signal for notification of wheel position detection thereby to set the transceiver device in a signal reception wait condition before transmission of the detection trigger signal, and to cause the trigger device to transmit the detection trigger signal after reception of a set signal from the transceiver device indicating that the transceiver device is set in the signal reception wait condition, and wherein the transceiver device is configured to intermittently turn on power supply to a trigger detector of the receiver for a predetermined period for setting the trigger detector in the signal reception wait condition, to turn on the power supply to the first controller and the transmitter when the trigger detector detects the notification trigger signal in the signal reception wait condition, to set the trigger detector in the signal reception wait condition by extending the predetermined period and to transmit the set signal to the receiver device upon reception of the notification trigger signal by the trigger detector, and to turn on the power supply to the first controller and the transmitter for measuring the signal magnitude of the detection trigger signal when the detection trigger signal is received in the signal reception wait condition.