An improved design and implementation of a broadband and wide axial ratio beamwidth circularly polarized parallel plate antenna

Abstract

This paper presents an improved design and implementation of broadband circularly polarized (CP) antenna that features a broad bandwidth and wide axial ratio (AR) beamwidth. First, the relationship between the three parallel plates (rectangular, semicircular, and semielliptical) and θ is analyzed. The semielliptical parallel plates (PP) used to obtain a wider 3dB AR-beamwidth (104^°×110^°×102^°×118^° at ϕ=0^°, 45^°, 90^°, 135^°, respectively) compared with rectangular and semicircular PP. Secondly, orthogonal crosses with 43^° inclined are used to generate orthogonal fields, and broadband characteristics can be obtained by adjusting the arm of orthogonal crosses. The semielliptical CP-PP antenna prototype was verified by ANSYS HFSS simulation. According to the measurement results, the -10dB return loss is about 20% (24.3-29.7GHz). A gain of 9.22dBic at 27GHz and a 3dB AR-beamwidth of 106^°×105^° at ϕ=0^° and ϕ=90^° are obtained. The designed semielliptical CP-PP antenna can be more beneficial to 5G millimeter wave applications.