Implications of Fresnel Corrections in a Non‐Gaussian Surface Scatter Channel

An investigation is made of the effect of the beam pattern of a source exciting an acoustic surface scatter channel using the Fresnel‐corrected geometric‐optics approximation. Results are presented for monochromatic and impulsive excitation using both deterministic and random boundaries. In the random case non‐Gaussian statistics are permitted for the surface deformations. This study concentrates on the limits of very narrow‐ and very broad‐beam patterns and specular geometry at moderate grazing angles. The results for the broad‐beam pattern are found to be simpler than the corresponding ones for narrow‐ and intermediate‐beam patterns. The theory is applied towards the calculation of impulse response convolutions and bifrequency spreading functions. An attempt is made to relate current and past physical results in a nomenclature suitable for application in signal processing and communication theory.