Analysis of M-ary Signaling for Weak Turbulence Regime in FSO Communication System

Abstract

Abstract: The need for high data rate LOS communication is accomplished using the Free Space Optical communication. Being a very cost-effective approach, it contributes to the easy set-up and deployment of point to point terrestrial link. It transmits the light signal in free space channel (air, vacuum etc.) using LASERs or LEDs and received via photodetector. In this paper, the channel is modelled using Lognormal turbulence model. This channel model is investigated for the weak turbulence regime and closed form expressions of average Bit Error Rate (BER) for M-PPM and M-PAM is proposed for a comparative analysis of the channel characteristics. The proposed analytical expressions are calculated using Gauss-Hermite integration and the results compared with their exact expressions. The results also discussed the effect of M, where higher value gives a better result for PPM and worse for PAM. In this paper, the maximum value of M is taken to be 16 and hence 16-PPM modulation provides the best results for the BER versus SNR among all the aforementioned modulation schemes.

Keywords: BER, SNR, Lognormal Channel Model, M-PAM, M-PPM

Cite this Article Aditya Pandey, Anupam Sahu. Analysis of M-ary Signaling for Weak Turbulence Regime in FSO Communication System. Trends in Opto-Electro & Optical Communication. 2019; 9(1): 24–31p.