Broadband patch antenna with low cross-polarisation

Abstract

A broadband differential-fed patch antenna with good radiation pattern is proposed. Unlike conventional differential-fed patch antennas, the proposed antenna employs a folded plate pair as the differential feeding scheme. To demonstrate the devised feeding approach, impedance bandwidth of up to 74% (SWR<2) has been achieved. More importantly, symmetric radiation pattern, low-cross polarisation level and stable radiation pattern are realised within the band.