Effect of Wall-Surrounded Slot on Stepped Narrow Wall for Bandwidth Enhancement of Partially Parallel-Feeding Waveguide Traveling-Wave Array

摘要

A partially parallel-feeding system of traveling-wave waveguide slot array has an advantage to reduce the frequency dependence of excitation phase of slots cut on the waveguide, which results in broadband feature of gain and radiation pattern. However, a conventional narrowband post-loaded radiating slot for array element limits the overall bandwidth of the array. A broadband wall-surrounded slot on a stepped narrow wall in the waveguide is proposed in this paper. The effects of the step on the waveguide narrow wall and the wall-surrounding slot are evaluated individually by electromagnetic simulation in this paper. The proposed antenna configuration of the waveguide assembled at the waveguide center allows fabrication by plastic molding with metal plating. The antenna performance is measured to confirm the feasibility of the proposed antenna in the millimeter-wave band.