Dual Polarized Antenna with Wide Beamwidth Utilizing TM01 Mode for X-Band Applications

Abstract

This paper presents a triple-port dual-polarized antenna designed for X-band applications with a wide beamwidth. The antenna utilizes 50 Ω probe feeding structure, resulting in a small size of 20 × 20 mm2. The proposed antenna is developed for X-band applications, operating at 10.7 GHz with a bandwidth of 200 MHz. The structure comprises two stacked substrates with electrical properties (2.2, and 4.5 permittivities, 1.5 mm height). The top layer features a rectangular patch with two ports for exciting orthogonal polarizations, while the middle layer includes a circular patch serving as a ground plane for the rectangular patch. The excitation of TM01 mode in the circular patch generates a conical radiation pattern, and the antenna exhibits an overlapping bandwidth from 10.3 GHz to 10.9 GHz. The peak gains, illustrated over the frequency range, reach 5.2 dBi for the circular patch and 7 dBi for the rectangular patch. Fabrication and measurements of the antenna demonstrate good agreement between experimental and simulation results.