Abstract: In order to determine the tire positions or wheel positions automatically while the vehicle is in operation, the attenuation along a transmission path from the tire to a fixed position on the vehicle is measured and compared with stored values. Systems of this kind are error prone when other vehicles using similar systems are located in the receiving range. In order to increase the reliability of such a system it is useful to determine the attenuation along the transmission paths between the wheel units and compare it with known values. Toward that end, the novel wheel unit enables data to be provided by way of which the attenuation of the transmission path from one wheel unit to another wheel unit can be determined.

Abstract: In the automotive industry that there is an increasing need for automatic tire pressure checking systems. One challenge here is to identify the positions of the tires on the vehicle. This is normally programmed-in it at the factory at the end of the production line. The tires however mostly do not remain in the same position during their lifetime. The invention allows a wheel unit to be automatically assigned to its wheel position on the motor vehicle. To this end the attenuation along a transmit path from a wheel unit to a transmission unit or receiving unit on the motor vehicle is determined. The attenuation determined is a characteristic value which allows conclusions to be drawn about the position of a wheel unit. An assignment by way of the attenuation has the advantage that the wheel unit is independent of variations in the transmit power of the transmission unit.