Tire condition monitoring apparatus, transmitter, and receiver

A tire condition monitoring apparatus comprises transmitters and a receiver. Each transmitter is provided in a tire and the receiver is provided in a body frame of a vehicle. The apparatus further comprises initiators each corresponding to one of the transmitters. Based on a trigger signal from the corresponding initiator, each transmitter wirelessly transmits a predetermined determination signal, which includes tire information, two or more times in a fixed time period from the transmission circuit. The determination signal from the transmission circuit is received by the reception circuit of the receiver and a controller determines whether there is a match between the received determination signals. When there is a match, the position of the tire is located and the tire information is processed as valid information.