An incremental `add-on´ approach to determining the effect of modification of the geometry of a thin plate on its electromagnetic scattering properties

The problem of rapid estimation of the effect of perturbing a thin plate structure is addressed using the add-on technique that was introduced recently by R. Kastner (see ibid., vol.37, p.353-61, 1989). An important feature of this method is its ability to make efficient use of previously computed results for the current distribution on a portion of the scatterer that remains unchanged as the geometry of the plate is modified. The procedure, which has been successfully applied to large irregular strip arrays and to a class of planar geometries that introduce negligible cross-polarization effects in the scattering process, is extended in this work to apply to arbitrary plates. In order to demonstrate the versatility of the method, numerical results are given for a number of plate geometries, including one with apertures