Multilook phase difference distribution for slightly rough boundary layered ground

The authors derive the distribution of phase difference between two multilook scattering signals for a multilayer stack with randomly rough surfaces under plane wave excitation. First, infinite slightly described by Gaussian centred stochastic processes, show that underlying complex follow joint distribution. Also, it is demonstrated this property within scope first-order perturbation theory. Secondly, use probability law to closed-form expression density function difference. theoretical formula verified comparison Monte-Carlo simulations.