Performance analysis of free space optical-based wireless sensor networks using corner cube retroreflectors

Asymmetric free space optical wireless sensor networks (FSO-WSNs) have gained momentous attention lately due to the promise of minimal energy consumption at the distributed sensors along with eminent performance. Asymmetric FSO is accomplished using corner cube retroreflector (CCR) that is mounted on each sensor node. The CCR either reflects or absorbs the received laser beam from the fusion center to indicate its local decision regarding the monitored target. In this study, a bistatic channel is assumed where the transmitter and the receiver are located at different locations such that the double pass channel is modeled as a product of two independent turbulence channels. Novel performance analysis of the CCR-based FSO-WSN system in terms of the average bit error rate (BER) and the average decision error rate (DER) is presented. In particular, closed-form expressions for the BER and the DER are derived using the Fox H-function under different bistatic turbulent channel models including negative exponential, K-turbulence, Gamma-Gamma, and Malaga channel models. Monte Carlo simulation results are obtained to corroborate the accuracy of the derived analytical formulas where an exact match is reported over wide range of system and channel parameters. In addition, the influence of transmit power, distance, detection threshold, and turbulence parameters on the performance of the system is investigated and thoroughly discoursed.