PULSE POSITION MODULATION FOR AN INFRARED VEHICLE-TO-ROADSIDE CDMA COMMUNICATION SYSTEM USING AN OPTICAL ORTHOGONAL CODE

In this paper, an infrared vehicle-to-roadside code division multiple access (CDMA) communication system is proposed. An optical orthogonal code (OOC) is employed as a signature sequence. Information data is modulated by L-ary pulse position modulation (L-PPM). It is assumed that a background light noise is an additive white Gaussian noise and infrared lightwave is dispersed during propagation. The bit error rate (BER) of the proposed system is evaluated by computer simulation. It is shown that the proposed system achieves smaller BER performance as the modulation order increases even when there is the dispersion of infrared lightwave. It is also shown that the proposed system with a (361,6,1,1) OOC has a smaller BER than that with a (181,6,1,1) OOC. For the covering abstract see ITRD E114174.