New results in applied scattering theory: the physical-statistics approach, including strong multiple scatter versus classical statistical-physical methods* and the Born and Rytov approximations versus exact strong scatter probability distributions

In order to carry out effective signal processing for signal detection and estimation in scatter-dominated environments, it is necessary to obtain the needed probability distributions and probability densities (PDFs) of the received scatter. In general, the received scatter is non-Gaussian and often strongly so. It is also dominated by multiple-scatter contributions. This is particularly the case for (radar) scatter off random interfaces at small angles, e.g.ocean wave surfaces and terrain, as well as acoustically (sonar) off the ocean surface and bottom. For ‘classical’ theory, based on statistical-physical (S-P) models and methods, the analytical construction of the required PDFs is beyond the general reach of S-P theory. The present paper reviews, amplifies and extends with new material the author's recently developed physical-statistical (P-S) alternative equivalent to classical (S-P) formulations. Here the fundamental innovation, starting with the basic Langevin equation of propagation in op...