Bandwidth and Beamwidth Improvement of Dual-Polarized Microstrip Antenna with Compact Size

In this paper, an improved dual-polarized distributed patch antenna is proposed to achieve broadband and wide-beam performance under reduced profile condition. Firstly, the differential feeding scheme is used to excite the patches on the diagonals, and the double-layer patches are used to expand the impedance bandwidth. Hence, the additional resonance is introduced on the feeding line so as to improve the impedance matching. As such, the frequency range where the return loss of the antenna is better than -10dB is ranging from 755 to 1005MHz (28%), which can cover low-frequency 5G communication bands: n5 (824MHz-894MHz), n8 (880MHz- 960MHz), and n20 (791MHz-862MHz). Meanwhile, the antenna has achieved a half-power beamwidth (HPBW) of more than 98° in the E-plane and more than 106° in the H-plane and a reduced height of 0.04λ0.