Mobile free space optic nodes in single-input multiple-output setup under transmitter misalignment

Wireless optical nodes with mobility capabilities (mobile free space optics [FSO]) have emerged as a way to overcome limitations inherent in FSO links, for example, transmitter–receiver restrictive alignment requirement. This paper proposes the use of an angular diversity model for characterizing the performance of mobile FSO over atmospheric turbulence, and transmitter–receiver misalignment switch-and-examine combining technique is suggested for a diversity combining under unbalanced multireceiving configuration. A laser beam is modeled as spatial Gaussian profile, and channel fading is modeled as a lognormal distribution with spatially uncorrelated samples. Analytical and statistical discussion on the resultant output is presented, and bit error performance and processing load are numerically evaluated and compared with those obtained using selection combining diversity schemes. Copyright © 2011 John Wiley & Sons, Ltd.