Patent ID: 8013725

Claim:
A tire pressure monitoring device comprising: pneumatic pressure monitoring units disposed at respective tires of a vehicle, including antennas, and arranged to measure pneumatic pressures of the tires and transmit results of the measurements of the pneumatic pressures from the antennas using radio signals; and a communication unit arranged to receive the radio signals from the antennas of the pneumatic pressure monitoring units; wherein the communication unit includes a single antenna arranged to receive the radio signals from the antennas of the pneumatic pressure monitoring units; and the communication unit is disposed in the vehicle, and is provided with a beam controller arranged to selectively set a directivity of the single antenna of the communication unit in directions of the respective tires such that, at any given time, the single antenna is directed at one of the tires, and the single antenna receives the radio signals from the pneumatic pressure monitoring unit disposed at the one of the tires at which the single antenna is directed at the given time; and each of the antennas of the pneumatic pressure monitoring units is a directional antenna arranged to transmit signals from the respective tire towards an inside of the vehicle in an axle direction of the respective tire.