volume | PIER Journals

Abstract

A broadband circularly polarized (CP) slot antenna array fed by an asymmetric coplanar waveguide (CPW) with stepped and inverted T-shaped strips is proposed. Using four square slot antenna elements with sequential rotation oblique feed and a modified sequential-phase (SP) feeding network, broadband CP can be achieved. The measured -10 dB reflection coefficient bandwidth and 3 dB axial ratio (AR) bandwidth are 55.4% (1.63-2.88 GHz) and 58% (1.65-3 GHz), respectively. Good radiation characteristics with gain more than 6 dBic over the operating band are obtained by the proposed antenna array with a compact size of 155×155×0.8 mm³. Details of the proposed antenna array design and experimental results are presented and discussed.

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Dr. Ping Xu

Dr. Ze-Hong Yan

Dr. Tian-Ling Zhang

Mr. Xiao-Qiang Yang