Abstract: A tire pressure control system for a vehicle having wheels with tires includes a controller and tire pressure sensors each having a transceiver. The sensors are within respective tires. Each sensor transmits information regarding the pressure of its tire to the controller. The controller transmits to the sensors a signal having markings based on rotation of a selected wheel. The signal as received by each sensor includes variations resulting from rotation of its associated wheel. The variations of the signal as received by the sensor corresponding to the selected wheel agree with the markings and the variations of the signal as received by each of the remaining sensors vary with the markings. Each sensor correlates the variations of the signal as received by the sensor with the markings. The sensor in which the variations of the signal agree with the markings transmits a confirmation regarding same to the controller.

Abstract: A tire pressure control system for a vehicle having wheels with tires includes a controller and tire pressure sensors each having a transceiver. The sensors are within respective tires. Each sensor transmits information regarding the pressure of its tire to the controller. The controller transmits to the sensors a signal having markings based on rotation of a selected wheel. The signal as received by each sensor includes variations resulting from rotation of its associated wheel. The variations of the signal as received by the sensor corresponding to the selected wheel agree with the markings and the variations of the signal as received by each of the remaining sensors vary with the markings. Each sensor correlates the variations of the signal as received by the sensor with the markings. The sensor in which the variations of the signal agree with the markings transmits a confirmation regarding same to the controller.

Abstract: A method and device for checking keyless vehicle access authorization of an operator. The method includes transmitting a code signal from a base station to a mobile identification (ID) transmitter carried by the operator. In response to receiving the code signal, the ID transmitter performs an action which is indicative of a reply signal that is detectable by the base station. The difference of a signal characteristic between a reference code signal monitored at the base station and the reply signal received by the base station is then determined. The signal characteristic correlates with signal propagation time and changes as a function of the distance between the base station and the ID transmitter. The distance between the base station and the ID transmitter is then determined on the basis of a relative determination based on the difference of the signal characteristic between the reference code signal and the reply signal.