Wideband Full-Corporate-Feed Waveguide Continuous Transverse Stub Antenna Array

A Ka-band waveguide continuous transverse stub antenna array with full-corporate-feed network is presented in this paper. Multiple-section stepped-impedance transformers are used for wideband impedance matching of the radiation slots. The required high-quality quasi-TEM wave excitation is generated by a wideband plane-wave generator (WPWG). Compared with the conventional pillbox structure, the WPWG produces a quasi-TEM wave with more uniform amplitude distribution. By using the combination of these design features, significant increases both in bandwidth and antenna aperture efficiency are achieved. For demonstration, a prototype is designed, fabricated, and measured. Excellent agreement is achieved between simulations and measurements. The antenna is matched over the entire Ka-band of 26-40 GHz. A high antenna aperture efficiency of over 75% and a low cross-polarization of less than -46 dB are achieved over the entire bandwidth. The demonstrated features of wideband, high aperture efficiency, and low cross-polarization have great potentials for millimeter-wave applications.