LAUSR

Abstract In this paper, a novel broadband differential antenna is designed. An active balun is utilized to realize the wideband differential feed to achieve low cross- polarization antenna radiation within the working frequency of 1.0–1.6 GHz. The active balun uses a common-gate/common-source structure to achieve two equal-amplitude signals with 180° phase difference. The differential antenna is composed of rectangular slot floor and symmetrical radiation patch. The antenna is fed by the out-of-phase output of the active balun. The tested results in 1.0–1.6 GHz show the cross-polarization of E and H plane of the proposed differential antenna are lower than −22 dB, with maximum radiation direction gain is 2.3 dBi. The measured reflection coefficient of the proposed differential antenna based on the active balun feed is in good agreement with the simulation data.