Performance analysis of integrated SAC-OCDMA and OFDM technique over FSO

Abstract

Recently, the free space optical communication (FSO) is gaining popularity because of its high data rate, license free spectrum, less power. The major drawbacks of FSO are absorption, scattering and atmospheric turbulence that affect the performance of FSO in terms of bit error rate (BER) and hence, limits the transmission distance. In this paper, novel integrated spectral amplitude coding optical code division multiple access (SAC-OCDMA) code is proposed referred in this work as pulse transposition-zero cross correlation (PT-ZCC) code. Orthogonal Frequency Division Multiplexing (OFDM) is of prime significance these days in long-haul communication systems because of its immunity to multipath fading, higher bandwidth proficiency, and its flexibility to interference. Therefore, the proposed PT-ZCC code is furthermore, integrated with the OFDM technique so as to improve the performance of the FSO system in terms of BER. In this work, the proposed PT-ZCC code is implemented over an integrated SAC-OCDMA and OFDM technique over FSO communication and is tested under several weather conditions. The proposed integrated scheme is also evaluated for different data rates and different number of active users. The proposed work is validated using Optisystem version 14.