Design of a 4 × 4 low profile continuous transverse stub antenna array

Abstract

This paper presents a low-profile and broadband continuous transverse stub (CTS) antenna array with a partially-corporate feed, demonstrating high efficiency and low cross-polarization. The array comprises eight radiating slots and is fed by a uniform partiallycorporate parallel-plate-waveguide (PPW) network combined with a novel linear source generator (LSG) of quasi-TEM mode. The LSG is constructed of four jagged-cavity groups excited by an H-plane ridged-rectangular-waveguide power divider. By using the partially-corporate feed structure, the conventional multi-layer PPW network is reduced to a single-layer one. The bulky pillbox coupler in conventional designs is eliminated and the profile of the CTS antenna array is reduced effectively. For demonstration, a prototype CTS array at Ka-band is designed, fabricated and measured. The proposed antenna is well matched (with a reflection coefficient less than −13 dB) over the frequency range of 34 to 41GHz. Excellent agreement is found between simulations and measurements. A high antenna efficiency of over 83% and low cross-polarization of less than −35dB are achieved over the entire bandwidth. The demonstrated features of low-profile, broadband and high aperture efficiency may find applications in multi-Gbps point-to-point wireless communications.