Ka-band microstrip array antenna with compact series-parallel hybrid strip-line feeding network

Abstract

This study proposes a Ka-band high-performance microstrip array antenna having a planar array front-end and strip-line back-end. 10 × 4 hybrid-fed rectangular patches with Taylor-synthesized excitation is adopted to form weighted patterns. Preferable symmetrical patterns are obtained covering 34.5-35.5 GHz working band due to the symmetric feeding arrangement. The measured reflection coefficient is lower than −10 dB, and peak co-polarization gain and first side-lobe level are better than 19 dB and −17 dB, respectively. Additionally, the strip-line back-end ensures an ideal front-to-back ratio of approximately 40 dB. The measurement results coincide with the simulation results, proving the immense prospect of our design in airspace detection or other applicable scenarios.