Code division multiple access based visible light communication in vehicle adaptive cruise control under emergency situation

Information broadcasting technique from vehicles to vehicles under emergency situation aiming adaptive cruise control is researched in this paper. At the transmitter, code division multiple access (CDMA) based intensity modulation to visible light beam is used, while at the receiver, a matched filter after direct detection is employed to recover the signal. Our simulation results indicate that for one thing, CDMA technique can help the system to realize broadcasting characteristic. When there is no CDMA, the system cannot work, while when CDMA is employed, the system can get a bit error rate (BER) performance of 10^-3. For another, CDMA can also help to resist the background noise. With the aid of CDMA technique, the system can get of BER of 10^-3 even in very heavy background noise. The system design can benefit the vehicle adaptive cruise control, especially under some emergency situation.