Performance of Cooperative System Based on LDPC Codes in Wireless Optical Communication

Abstract

This paper proposes the use of the technique of cooperative systems in wireless optical communication. Several obstacles can degrade the performance of information transmission in wireless optical links. These include atmospheric turbulence in communication links greater than 1 km, the rocking of buildings, wireless optical channel fading and flickering. Several studies have shown that the use of cooperative systems in this communication technique has better performance compared to conventional systems. To improve the performance of the transmission in the optical links we propose to place a DF (Decode and Forward) relay between the transmitter and the receiver, using the LDPC (Low-density Parity-check) codes at the relay level. Another innovation of this article is the introduction of the series relays to connect two very distant sites by also using LDPC at the level of each relay. Our method achieves a remarkable efficiency in terms of BER (Bit Error Rate) compared to some previous work.