Patent ID: 6931923

Claim:
A tire condition monitoring apparatus that monitors a condition of a tire of a vehicle, the apparatus comprising: a transponder provided in the tire, wherein, in response to a predetermined interrogating radio wave, the transponder detects a condition of the tire and wirelessly transmits data representing the detected condition of the tire; and a transmitter-receiver provided in a body frame of the vehicle, wherein the position of the transponder relative to the transmitter-receiver changes as the tire rotates, wherein the transmitter-receiver transmits the interrogating radio wave and is capable of receiving the data wirelessly transmitted by the transponder, wherein, in at least a part of a period during which the tire rotates through one revolution, the transponder passes through a communication range, in which communication between the transmitter-receiver and the transponder is possible, and wherein the transmitter-receiver has a controller that controls the transmission of the interrogating radio wave such that the interrogating radio wave is transmitted while the transponder is in the communication range.