Error Probability and Laser Beam Propagation Analysis in Local Area Optical Wireless Communication Networks Using Pulse Position Modulation Technique under Atmospheric Turbulence Effects

Abstract—Free space optics (FSO) is a promising solution for the need to very high data rate point-to point communication. The atmospheric turbulence effect on FSO communications is one of the biggest problems that face FSO systems. This paper has presented the laser beam intensity fluctuations, laser beam spreading with its loss, and receiver arrival angle fluctuations in atmospheric turbulence free space optical communication systems. Our numerical results show that using APD with a proper selection of the average gain could greatly benefit the performance of the free space optics system with pulse position modulation. We have taken into account the impact of link conditions and system parameters on the selection of optimal Si APD gain. Signal to noise ratio (SNR), and bit error rate (BER) are the major interesting parameters in the current research. As well as we have compared our simulation results using silicon APD (Si-APD) receiver with their simulation results using InGaAs APD receiver. Index Terms — Laser intensity fluctuations, turbulence channel, Free space optics, Pulse position modulation, and Avalanche photodiode receiver. I