US Patent 8947265 Signal timing coordination system for crosswalk beacons

A signal or lighting system synchronizes the flashing of multiple signal or lighting assemblies. When one of the assemblies is triggered, it broadcasts a temporally staggered sequence of signals, each signal instructing the receiving assemblies to initiate flashing of their beacons a given countdown time after that particular signal is transmitted. The countdown times of the various signals all count down to the same flashing start time so that the originating and receiving beacons all being flashing at the same time. The temporal diversity of the signals enhances the ability to overcome potential interference as at least one of the signals in the sequence is likely to be received by the destination assemblies.