HIGHWAY SYSTEM AND VEHICLE COMMUNICATION WITH LASER OPTICS

Laser optics open-air communication system (LOOC) can be described as fiber optics communication without the need for a connecting fiber. It has wide signal bandwidth and complete mobility. Both the transmitter's beam direction and the receiver's direction of sensitivity are electronically controlled with sub-microsecond time constants. A novel device in LOOC is a directed and focusing laser, which can be described as an array of electronically phase-controlled optical paths, on a single semiconductor chip. Its use substantially reduces the required signal power, interference, hazards to the human eye, and communication terminals cost. The vehicle and the highway system can communicate in the following manner. On the highway side is a system of infrared lightwave transmitting-receiving terminals (HWST) that are linked via computer communication networks to a traffic information and control center. Each terminal has a built-in two-way signal storage and forward device that could be, for instance, a specially programmed microprocessor. The highway terminal is mounted on an overhead structure and a similar terminal device (VT) is installed on each vehicle. The terminals communicate with each other as the vehicle passes under the overhead structure without stopping or slowing down. Assuming that communication starts when the VT is 15 m from HWST and stops at a distance of 5 m, and that binary error detection code with retransmission is used, 10 bytes can be exchanged virtually error free during each encounter under all weather conditions.