Design of a Wideband Circularly Polarized Cross-Dipole With Wide Axial-Ratio Beamwidth

Abstract

A novel wideband circularly polarized (CP) cross-dipole with wide 3 dB axial-ratio (AR) beamwidth is presented. To generate CP radiation, the cross-dipole is fed by a Wilkinson power divider which can provide 90 • phase difference. The gain beamwidth and 3 dB AR beamwidth can be widened by the bent arm structures of cross-dipole and four vertical parasitic elements. As a result, the 3 dB AR beamwidth and gain beamwidth of the proposed antenna can achieve over 210 • and 105 • , respectively. It is observed that the impedance bandwidth (|S 11 | ≤ −10 dB) of the proposed antenna is 1.2 ∼ 2.0 GHz, and the AR bandwidth (AR ≤ 3 dB) is 1.28 ∼ 1.76 GHz. The simulated and measured results are in good agreement, which shows that the proposed antenna is a good candidate for the application of satellite communications.

Ultra‐high‐frequency wideband circularly polarized crossed‐dipole antenna with wide axial‐ratio beamwidths for SATCOM applications

“…However, antenna ARBW bandwidth over 190° in Ref. is 19.0%, which is narrower than the proposed design, and comparing with the antenna in Ref. , the proposed antenna gets a smaller volume.…”

“…It is worth noting that the proposed antenna has a wider ARBW (ARBW>190 : 23.1%) and maximum ARBW than the other referenced antennas except for the design in Ref. 9. However, antenna ARBW bandwidth over 190 in Ref.…”

“…, CP crossed dipoles with four parasitic elements obtain an ARBW of more than 120°. And recently a CP folded crossed dipole was proposed to realize an ARBW of more than 210° based on the same principle . So far, achieving a wide ARBW of more than 190° within a broad operating band is still a challenge.…”

“…And recently a CP folded crossed dipole was proposed to realize an ARBW of more than 210 based on the same principle. 9 So far, achieving a wide ARBW of more than 190 within a broad operating band is still a challenge. In this article, four elaborately designed parasitic elements are utilized to improve the AR beamwidth performance and AR bandwidths.…”