ANALYSIS OF TM SCATTERING FROM FINITE RECTANGULAR GROOVES IN A CONDUCTING PLANE

Abstract

TM-wave scattering from rectangular grooves in a perfectly conducting plane is investigated. A Fourier-transform technique is employed to express the scattered field in the spectral domain as a superposition of the parallel-plate waveguide modes. The boundary conditions are enforced on the conducting surface and the groove apertures to obtain simultaneous equations for the transmitted field inside the grooves. The simultaneous equations are solved to obtain the transmitted field in a series representation that reduces to a closed form in a high-frequency scattering regime. With the use of the stationary phase approximation, the far-zone scattered field is obtained, and its scattering behavior is studied in terms of the scattering angle. The diffraction efficiency for the finite grating as the number of grooves increases is presented.