A Novel Dual-Polarized Millimeter Wave Filtering Antenna for 5G Applications

In this paper, a novel dual-polarized filtering antenna (filtenna) is proposed for millimeter-wave (MMW) applications. The principal part of the filtenna is composed of the stacked antennas and eighth-mode substrate integrated waveguide (EMSIW) cavity. The stacked patch antennas can bring other resonance points, so as to broaden the bandwidth of the antenna. To realize the filter function, EMSIW is introduced into the filtenna. A cross element and four-square patches are used for radiation. Short-circuit and open-circuit branches are introduced into the transmission line of the filtenna to generated radiation nulls at higher and lower stopband, which can further improve the suppression ability. The filtenna of our proposed operates at the n258 band (24.25 GHz to 27.5 GHz). The gain at lower stopband decreases over 23 dB and in higher stopband decreases over 15 dB. Meanwhile, the average gain in operation band is about 4 dBi.