Waveguide design considerations in annular waveguide slot antennas (AWSA)

In this paper, modal considerations for design of an annular waveguide for application in annular waveguide slot antennas (AWSA) were considered. It was shown that such cavity could be designed to have resonant characteristics at our operating frequency. Based on this result, resonant half wavelength slot could be drilled in various waveguide faces and a novel slotted antenna (AWSA) is achieved. The structure is fabricated and simulation and measurement results are compared with those of theory. A possible AWSA array configuration is depicted in Fig. 4. Such planar array of the presented AWSA could be employed to improve the performance of planar waveguide slot arrays in terms of polarization, gain, aperture efficiency and discretizing error in the future.