Efficient Evaluation of the External Mutual Coupling in Dielectric-Covered Waveguide Slot Arrays

An accurate and efficient procedure is devised to evaluate the mutual coupling in dielectric-covered planar arrays of longitudinal slots. This approach takes full advantage of the discrete complex image method to cast the spatial-domain Green's functions into closed forms, and hence a direct calculation of mutual coupling in the spatial-domain is available. The computation time reduces significantly compared to the previous spectral-domain procedure, without any loss in the accuracy, rendering this approach very attractive for the design of large dielectric-covered planar arrays.