Scattering from a trough in a ground plane

We present a solution to the problem of determining the electromagnetic fields scattered by a two-dimensional trough in a perfectly conducting ground plane. The solution uses the moment method applied to a set of integral equations developed by Asvestas and Kleinman (see IEEE Transactions on Antennas and Propagation, vol.42, no.1, p.22, 1994). We compare the accuracy of this technique to the hybrid finite element method/boundary integral (FEM/BI) method for the special case of a rectangular trough. We further show that this technique does not exhibit the spurious resonances which can afflict other integral equation based approaches.