Accurate prediction of finite waveguide array performance based on infinite array theory

The S-matrix of a finite waveguide array is constructed using the element coupling coefficients obtained from an infinite array model. This S-matrix is modified when an external ground plane is present or when feed modules are attached to the array elements. Given the port inputs, the final waveguide aperture excitations, which include the effects of mutual coupling, can be calculated using the modified S-matrix. Using the known isolated element pattern, the finite array pattern can also be computed.