Performance Improvement In Sim Based Fso With Apd Receiver By Using Spatial Diversity Techniques Over Turbulent Channels

In this work, we theoretically investigate the performance enhancement in the free space optical (FSO) communication system with binary phase shift keying-subcarrier intensity modulation (BPSK-SIM) using spatial diversity techniques. We have used APD based receiver in this study for better results. Moreover, the channel attenuation factor is used for more appropriate analysis of the system bit error rate (BER). The BER expressions are theoretically derived for the case of weak-to-moderate turbulent condition using log-normal channel modeling. We have discussed the influence of turbulence strength, link distance and bit rate on the system BER performance with respect to the average received irradiance.