Compact Differentially-Fed Rectangular-Ring Microstrip Antenna

Abstract

In this paper, a design of compact differentially-fed rectangular-ring microstrip antenna is proposed. In order to effectively excite the dominant TM01 mode, two feed points are chosen with an offset from the symmetric axis. The simulation indicates that the resonance of the TM01 mode occurs at 4.395 GHz, which results in a maximum gain of 7.53 dBi. Benefited from the differential signal operation, a relatively weak cross-polarization can be achieved.