An optical CDMA method for in-vehicle information service

This study proposes a new inter-vehicle communication (IVC) system based on optical spectral-amplitude-coding optical code division multiple access (SACOCDMA) systems architecture, then, analysis and calculate the system´s performance by using analytic and simulation methods. The important feature of the SAC-OCDMA systems is that multiple access interference (MAI) can be eliminated by code sequences of a fixed in-phase cross-correlation value with balance detection schemes. The advantage of optical CDMA multiplexed method compared with electrical multiplexed method is no electromagnetic interference and security enhanced. The performance of modify prime codes (MPCs) and Walsh-Hadamard codes as signature codes for the SAC-OCDMA systems is analyzed. The simulation results of MPCs in SAC-OCDMA system structures are first presented by commercial simulation obtained using OptiSystem software. The simulation results show that the bit error rate (BER) through use of the MPCs is superior to the conventional Walsh-Hadamard codes, especially when the received effect power is large. The eye diagram also shows that the SAC-OCDMA system with MPCs exhibits a wider opening than the Walsh-Hadamard codes.