Analysis of an offset cross slot in the broadwall of a rectangular waveguide using the Galerkin method

A novel type of radiating element for slotted waveguide arrays: offset cross slots in the broadwall of a rectangular waveguide is put forward. Scattering and resonant properties of a single offset cross slot are analyzed using the Galerkin method with global sinusoidal basis. Numerical results reveal that such an element can be represented by an admittance in a transmission line, just as an offset longitudinal slot does. However, it possesses a shorter resonant length and a broader bandwidth, compared with the offset longitudinal slot. The agreement between theory and experiment is found to be good, which verifies the accuracy of our method.