Abstract: A communication system for communicating spoken speech, based on switching on and off a visible or infrared light source in a pattern corresponding to the spoken speech. The communication system provides for rapid retransmission/rebroadcast of messages received from other communication systems, to allow communication over a longer range than would otherwise be possible, or between two points not along a line of sight. The system may include a light source also used (at the same time) for providing illumination, such as a light source that is part of a lightbar mounted on a vehicle.