Miniaturized Rectangular Leaky Waveguide Antenna With Fixed-Beam Radiation and High Power-Handling Capacity

A fixed-beam leaky waveguide antenna (LWA) featuring a miniaturized structure for high-power microwave (HPM) applications is proposed in this paper. A wedge-shaped compensation prism is introduced in the radiating aperture of the waveguide to fix the beam direction. The incorporation of this prism generates dual refraction of electromagnetic waves (EMW): first at the waveguide-prism interface, and second at the prism-free space interface. To reduce the transverse dimensions of the prism, a binary dispersion compensation method based on the binary refraction phenomenon of LWA is proposed and deduced. This method also provides flexibility in tailoring the radiating angle. Further investigations are carried out to reduce the maximum electric field strength of the waveguide and the prism for HPM applications. Experimental results demonstrate that the pitch angle of the miniaturized compensation prism is reduced from 30° to 10° and the radiating angle is tailored from 43° to 31.1° in a squint-free bandwidth of 3.9-4.5 GHz by employing the proposed method, with gain stabilizing at 16.6-18.4 dBi. The power-handling capacity (PHC) of the LWA is about 121 MW under the vacuum condition, which is intended for applications in directed HPW scenarios.