Miniaturized Broadband Dual-Polarized Dipole Antenna Based on Multiple Resonances and its Array for Base-Station Applications

作者：Yang, Wanchen; Li, Yongzheng; Xue, Quan; Liao, Shaowei; Che, Wenquan^*

来源：IEEE Transactions on Antennas and Propagation, 2022, 70(11): 11188-11193.

DOI：10.1109/TAP.2022.3209273

• Base-station antenna
• broadband antenna
• dipole
• dualpolarization
• miniaturization

A novel bandwidth enhancement method using loading multiple parasitic structures to realize broadband miniaturized antenna is proposed. Based on the proposed strategies, one miniaturized wideband dual-polarized dipole antenna covering LTE/CDMA/GSM bands (690-960 MHz) for base-station application is designed. The antenna consists of two folded bowtie-shaped dipoles fed with a pair of crossed baluns, and is further loaded on a ceramic block with high permittivity (epsilon) for miniaturization. A parasitical square loop is loaded for bandwidth enhancement at a lower frequency. In addition, four split rings with a small square loop are firstly adopted for antenna resonance tuning, the impedance bandwidth is thus improved effectively. The antenna size is only 0.18 x 0.18 x 0.22 lambda(0) at the center frequency. The measured result of the fabricated prototype exhibits a relatively large operation bandwidth of 32.73% (VSWR < 1.6) with stable radiation patterns and relatively flat broadside gains. Moreover, to verify the feasibility of the proposed miniaturized antenna element in the base-station application, an array of 2 x 4 is further designed. The measured results of the array indicate isolation over 20 dB with an impedance bandwidth of 32%. Due to the good performance and compact feature, the proposed miniaturized broadband antenna element can find large application potential in multiband wireless communication base stations.