Cavity-backed high-gain switch beam antenna array for 60-GHz applications

摘要

This study presents a cavity-backed aperture-coupled switch beam antenna array for 60-GHz applications. A 1 × 4-element cavity-backed aperture-coupled patch antenna array is adopted as the radiating part, which is fed by the Butler matrix feed network that consists of couplers, crossovers, and phase shifters. By using the cavity that can help suppress the surface wave propagation along the substrate, the array not only achieves a high-aperture efficiency and gain but also maintains a wide beam steering angle in the -plane. The feed network is designed by using substrate integrated waveguide (SIW) technology with a low profile, low radiation loss, and low cost. Measured results show the array exhibits wide -10-dB impedance bandwidths of 12.6% (56.6-64.2 GHz) for port 1 and port 4 and 11.6% (56.8-63.8 GHz) for port 2 and port 3. The beam angle coverage is from -38° to 38° with good steerable radiation patterns.