A General Approach for Determining the Irradiance Distribution of EM Waves Propagating Through Random Media

The derivation of the probability density of irradiance for the received electromagnetic wave propagating through random inhomogeneities has applications in many diverse fields, such as optical wireless communications, radar, and imaging systems, to name few. The conventional approach in this regard is to combine distribution models, with each being found valid under different conditions, in a modulation process, e.g., the extended Rytov theory. However, in these techniques, the nature of the physical processes responsible for the randomness is not considered directly. Moreover, it is not clear how the model parameters are related to the physical environment. Recent research studies found that in random media, such as underwater, the exact physical processes in effect can significantly alter the distribution of the received signal intensity. In this article, a novel intensity distribution model is derived based on Rytov theory of propagation through weak turbulence. The physical parameters of the medium are directly included into the model parameters. Therefore, the resultant model is general enough to describe different physical environments. The utility of the model is validated by studying the effect of the medium parameters on the distribution through simulations.