Performance Enhancement of Multi channel Multi Beam FSO Communication link with the application of Reed Solomon codes

Abstract The rise in user’s requirement for high speed applications and services has necessitated the requirement of a communication link that can provide the data rate comparable to optical fiber. Free Space Optical (FSO) Communicationis being admired means of communication from past few years. To achieve seamless and error free transmission at high speed for heterogeneous multimedia applicationsat desired bit rates, novel advancements in optical communication technology are being explored along with FSO. However, several constraints such as atmospheric turbulence, uneven terrain, dynamic climatic conditions cause several nonlinearities which limits the connectivity. In this work, a multi channel multi beam FSO communication system by incorporating Reed Solomon (RS) Codes has been proposed at 30Gbps. The Modified Gamma-Gamma model is beingapplied for channel turbulences. The application of forward error correction (FEC) coding in the designed system offers ease of error detection and correction with improved performance at higher data rate for implementation over longer link lengths.The system performance has been evaluated for (i) Number of errors corrected, (ii) Bit Error Rate (BER), (iii)Received power, (iv) Geometric path losses and (v) SNR. At an acceptable BER of 10− 9, the RS (255, 127, 129) encoded four channel four beam FSO communication link to be effectively implemented for a distance of 3500m with − 32.5dBmreceived low optical power and 25 dB SNR.