Channel Modeling and Performance Analysis of Modulating Retroreflector FSO Systems Under Weak Turbulence Conditions

This paper presents the fading channel of double-pass modulating retroreflector free-space optical systems under weak turbulence conditions that can be modeled by the distribution of the weighted product of two correlated Lognormal random variables. We first show the proposed channel model through using wave-optics simulation. Then, the probability density function (PDF) and cumulative distribution function (CDF) of the channel model are derived in closed form. The system bit error rate (BER) and outage probability are calculated by averaging the conditional BER of on-off keying (OOK) modulation over the PDF and substituting the signal-to-noise ratio threshold into the CDF, respectively. The obtained analytical formulas for the system performance are validated by Monte Carlo simulations. Moreover, the effect of the fading correlation and the aperture averaging on the performance is investigated.