Abstract
The diffraction of plane electromagnetic waves by three parallel thick impedance half-planes is investigated rigorously by using the Fourier transform technique in conjunction with the mode matching method. This mixed method of formulation gives rise to two scalar modified Wiener-Hopf equations of the second kind for odd and even excitations respectively. The solution of each Wiener-Hopf equation contains a set of infinitely many constants satisfying an infinite system of linear algebraic equations. A numerical solution of this system is obtained for various values of the plate impedances, plate thickness and the distance between the plates, wherefrom the effect of these parameters on the diffraction phenomenon is studied.