A single‐layer Ka‐band broadband reflectarray antenna using log‐periodic elements

Abstract

AbstractThis letter presents a novel log‐periodic reflectarray element based on a single‐layer substrate. To achieve a full 360° phase coverage with a gentle slope, the corresponding parameters are optimized. For the sake of minimizing the effects of the feed blockage, the proposed element is used to construct a Ka‐band offset‐fed reflectarray antenna whose aperture size is 81 mm × 81 mm. Moreover, a corresponding prototype is also fabricated to test the actual radiation performance. The measured maximum gain is 26.65 dB at the center frequency of 33 GHz with the aperture efficiency of 46.34%. Moreover, the measured peak sidelobe for E‐plane is lower than −17.87 dB and 10.69% of 1‐dB gain bandwidth is also achieved, which demonstrates that the proposed antenna features the characteristic of broadband. The simulated and measured results show that the proposed antenna features good radiation performance, which has the potential for 5G communication systems.