Wave-oriented processing of scattered field data from a plane-wave-excited finite array of filaments on an infinite dielectric slab

In a companion paper, we presented the formulation and solution for time-harmonic plane wave fields scattered by truncated periodic and aperiodic arrays of infinitely long filaments on an infinite dielectric slab. The solution was constructed so as to highlight the coupled phenomenologies associated with slab loading of the Floquet mode beams characteristic of the truncated arrays and with the slab-guided leaky modes excited by these arrays. Asymptotic reduction of the solution yielded a parameterization of the scattered fields and a numerically accurate algorithm, based on physically observable ray- and mode-field constituents. The present study is concerned with the inverse procedure of extracting from the scattered field data the phenomenological footprints of the scattering mechanisms found by forward problem asymptotics; this information is relevant to target classification and identification. The data processing tools involve Gaussian windowed transforms and superresolution algorithms that yield projections onto appropriate subdomains of the (space)-(spectral wave number) phase space. A variety of examples demonstrate physically and quantitatively the interplay of Floquet-mode and leaky-mode phenomena, and how these are affected by changes in the problem parameters. Of special interest is the performance of superresolution algorithms for "cleaning up" the diffuse Gaussian windowed phase space distributions, in the absence and presence of system noise. © 1996 IEEE.