US Patent 7205908 Systems and methods for proximity control of a barrier

A system and method for proximity control of a barrier comprises a stationary wireless signal receiving device and a mobile transmitting device. The wireless signal receiving device may monitor at least one transmitting device within a predetermined coverage area and may be a radio frequency receiver or a spread spectrum receiver located near the barrier. In one embodiment, the transmitter device emits a control signal that is received by the receiving device when the transmitter is within a reception range. In one embodiment, the control signal includes transmitter identification information, directional information and position information. In another embodiment, the barrier is closed only after a predetermined delay has lapsed.