Finite-element analysis of parallel-plate feeds for linear phased arrays

The finite-element analysis of conducting waveguides is modified to replace two conducting walls by two phase-shift walls. This simulates an infinite periodically fed parallel-plate type structure, which serves as a feed for an infinite linear phased array. The cutoff wavelengths and field structure of the lower modes are calculated for different geometries and phase shifts. A mode splitting effect is observed for phase shifts larger than ¿¿.