Multiple transceiver synchronous communication system

Abstract

A vehicle transceiver module is provided for use in a synchronous communication system including the vehicle transceiver module and one or more key fobs, each of the key fobs including a key fob transceiver for transmitting and receiving signals. The vehicle transceiver module includes transceiver circuitry, a controller, a storage device and power control circuitry. The transceiver circuitry receives the signal transmitted by the key fob transceiver and provides it to the controller. The controller is coupled to the transceiver for determining an offset value associated with one of the key fobs in response to an offset time duration between a reception time of the signal from the key fob and a first expected reception time of the signal from the key fob. The storage device is coupled to the controller for receiving the offset value associated with the key fob from the controller and stores the offset value along with information identifying the key fob. The power control circuitry is coupled to the transceiver circuitry for providing operational power thereto. In addition, the controller is also coupled to the power control circuitry and provides a begin transmission signal thereto to power up the transceiver circuitry for transmission of a signal to the key fob at a transmission start time determined by the controller in response to the offset value associated with the key fob and a second expected reception time.