A Differentially-Fed High-Gain Tri-Band Hybrid Antenna for 2.4/3.5/5.2 GHz

In this paper, the technique of hybrid modes of patch, slot and dipole antennas is proposed for generating triple bands. A simple ultrawideband out-of-phase power splitter (OPS) is first designed with equal power splitting and accurate phase difference of 180o between the two output ports. Then, the OPS is used to feed the radiator, consisting of a rectangular patch, a slot and a dipole, which are integrated into a single substrate. Simulated results show that the antenna has a tri-band of 2.39-2.50 GHz (4.5%), 3.41-3.73 GHz (9.0%), 5.15-5.35GHz (3.8%), with the corresponding peak gains of 6.6, 8.2 and 7.0 dBi, respectively. The radiation patterns are unidirectional, symmetrical and stable within the three bands, and the cross-polarization is lower than 26 dB.