Cavity-Backed Circularly Polarized Cross-Dipole Phased Arrays

In this letter, a 16 x 16 Ku-band circularly polarized phased array is proposed. The antenna element comprises a cross dipole, a metal cavity, and a threaded SMP connector. The metal cavity makes the gain of the antenna increased and the mutual coupling between the array elements is reduced, thus ensuring good impedance matching and axis ratio (AR) during the two-dimensional beam scanning. The mutual coupling of the center element at center frequency is -26.6 dB when the cavity is added. The proposed phased array achieves the impedance bandwidth (vertical bar S-11 vertical bar <= -10 dB) of 10.1% (13.1-14.5GHz) when scanning +/- 40 degrees in the xz plane and yz plane. AR of themain lobe is less than 2 dB in the total scanning range. The gain fluctuation is less than 3 dB during scanning. This letter presents the measurement and simulation results, verifying that the phased array has good performance.

Automated summary

This research introduces a novel Ku-band circularly polarized phased array antenna with high gain and low mutual coupling, ensuring good impedance matching and axis ratio during beam scanning. Experimental results demonstrate the stable performance of the phased array.