Tri-polarization Reconfigurable Fabry-Perot Resonator Antenna in Ku-band

In this paper, a broadband tri-polarization reconfigurable antenna applied to polarization diversity is proposed. A partially reflective surface (PRS) is designed to form an air-filled resonator cavity. The reflection phase of the PRS has a positive phase gradient in order to achieve the characteristics of the proposed antenna gain enhancement in the wideband. A metal patch of a four-arm meander structure is used as the radiation structure and the feeding is realized through a four-channel rotating feeding network with equal amplitude and 90 degrees phase difference. The feeding network is connected to the radiation structure through four metallized vias. In order to realize the polarization reconfigurability, the PIN diodes and the corresponding DC bias circuit are integrated in the rotating feeding network. The characteristics of horizontal polarization (HP), vertical polarization (VP) and right-hand circular polarization (RHCP) are realized by changing the ON/OFF states of PIN diodes integrated in the feeding network. In order to verify the performance of the proposed antenna, fabrication and testing were carried out. The measurement results show that the -10 dB impedance bandwidths of HP, VP, RHCP are 11% (12.5-14 GHz), 6.4% (13.7-14.6 GHz) and 20% (12.2-14.9 GHz), and the peak realized gains are 9.1, 9.2 and 11.5 dBi, respectively. For RHCP mode, the 3-dB axial ratio bandwidth reaches about 17% (12.35-13.4 GHz and 13.6-14.9 GHz).