Modeling and Analysis of Hybrid SIM with L-PPM and MSK over Double Generalized Gamma Distribution in Free Space Optical Communication System

In this paper, we use Double Generalized Gamma (GG) distribution in turbulence induced fading to model the communication channel under weak, moderate and strong turbulence condition. In order to further improve the performance of Free Space Optical (FSO) Communication system over Double GG distribution, we use Hybrid Subcarrier Intensity Modulation (SIM) with L-Pulse Position Modulation (L-PPM) and Minimum Shift Keying (MSK) and analyze its Bit Error Rate (BER) performance for average received irradiance between -12 dBm and 4 dBm. From the simulation results, we observe that BER decreases with decrease in average length of PPM symbol L under different turbulence conditions in FSO Communication system.