On the Analysis of slotted waveguide arrays

A strategy for the full-wave analysis of slotted waveguide planar arrays is presented and demonstrated. The core of the method is a suitable segmentation of the antenna into two fundamental regions: an "internal" one, formed by the waveguide circuit, and the "external" one, consisting of the half space above the plate where the radiating slots are located. The internal region is further segmented into several blocks, connected to each other via their generalized admittance matrices (GAMs). The latter are calculated by means of either a commercial or a home made tool. The front plate is considered as a whole and analyzed by the moment method, in terms of modes of the slots. The latter are considered as short sections of waveguide whose length is just the conductor thickness, connecting the internal and external regions. The approach has been applied with success to a number of large planar arrays, both in rectangular and ridge waveguide.