Performance Analysis of AF Relayed NLOS UV Communication Over Turbulent Channel

Ultraviolet (UV) communication experiences strong aerosol and molecular scattering which leads to non-line-of-sight (NLOS) connectivity. As the UV signal propagates through the atmosphere, the change in the refractive index of the atmosphere causes random fluctuations in the transmitted signal, this phenomenon is referred to as turbulence. The effect of atmospheric turbulence in NLOS UV communication link is usually ignored under the assumption of short distance communication. In this paper, we consider a NLOS UV communication system experiencing fading due to atmospheric turbulence and use relay-assisted transmission for improved connectivity. We present performance analysis of dual-hop amplify-and-forward (AF) relayed outdoor NLOS UV communication and derive closed-form expressions for the outage probability, average symbol error rate, ergodic capacity and relative diversity order. Analytical expressions using two different approximations are compared and validated with simulations.