US Patent 9253753 Vehicle-to-vehicle safety transceiver using time slots

A transceiver in a vehicle-to-vehicle (V2V) communication and safety system that regularly broadcasts safety messages, comprising location, heading and speed, of a subject vehicle, that are free of MAC and IP addresses. The V2V system uses the location of the subject vehicle for vehicle identification, in place of a pre-assigned vehicle ID. Some embodiments broadcast safety message in self-assigned time slots in a synchronized TDMA broadcast architecture, with unusually short inter-message gaps and unusually short messages. The TDMA frame is partitioned into three prioritized time interval classes with differing priorities and dynamically changing sizes based on demand of higher-priority messages. Time slot selection uses weighted algorithms. Selected time slots are held until either a message collision or a timeout occurs. A transceiver equipped vehicle may proxy a different subject vehicle. Embodiments include optimized traffic flow and signal timing.