Experimental study on radiation characteristics of probe-fed suspended plate antennas

Recently, a new kind of suspended plate antennas (SPAs) has been proposed to enhance impedance bandwidth. With the broadened bandwidth, however, the radiation performance of the SPA severely deteriorates because of high cross-polarization levels in H-planes and distorted copolarization patterns in E-planes. In this paper, the experimental studies on the radiation characteristics of broadband probe-fed SPAs are conducted. First, non-radiation probe-driven feeds are designed. Second, the far-field radiation characteristics of the SPAs fed by the proposed non-radiation feeds are examined. Last, the effects of the induced electric current distributions at the plates on the co- and cross-polarization radiation patterns are discussed.