Theoretical Analysis of Optical Wireless CDMA with Modified Pseudo Orthogonal M-Sequence Sets

Abstract

In this paper, to increase normalized throughput of the optical wireless code-division multiple-access (CDMA) system, modified pseudo orthogonal M-sequences (MPOMS) are considered as optical pseudo-noise (PN) code. Moreover, the bit error rate (BER) performance of the optical wireless CDMA system using multi-pulse pulse position modulation (MPPM) is also derived in the presence of the scintillation, background-noise, avalanche photo-diode (APD) noise, thermal noise and signal dependence noise. Consequently, the BER performance in consideration of normalized throughput of the MPPM system with MPOMS is superior to that of the MPPM system with conventional pseudo orthogonal M-sequences in the single-user case and multi-user case.