A wheel identifying apparatus according to the present invention includes
a plurality of transceivers, a triggering device, a receiver, and a wheel
identifier. Each of the transceivers is located on one of a plurality of
wheels of a vehicle and works to receive a trigger signal and transmit a
response signal in response to receipt of the trigger signal. The
triggering device is located on a body of the vehicle at different
distances from the transceivers and works to transmit the trigger signal.
The receiver works to receive the response signals transmitted by the
transceivers. The wheel identifier is operatively connected to the
receiver and works to identify, for each of the response signals received
by the receiver, the wheel on which the transceiver having transmitted
the response signal is located using the fact that strengths of the
trigger signal at the transceivers are different from each other.