Ku波段宽带高增益基片集成腔圆极化阵列天线

Ku-Band Broadband High-Gain Substrate Integrated Cavity Circularly Polarized Antenna Array

提出了一款应用于Ku波段的宽带高增益基片集成腔(Substrate Integrated Cavity,SIC)圆极化阵列天线。通过引入沿SIC口径面对角线放置的一对半月形寄生贴片和SIC底部馈电纵缝,使SIC中的TM_(211)和TM_(121)谐振模式幅值相等、相位相差90°,产生高增益圆极化辐射。同时,双寄生贴片还引入了一种背腔缝隙耦合振子圆极化辐射模式,扩宽了天线高增益圆极化辐射带宽。在此基础上,设计了一款2×2单元顺序旋转馈电的SIC圆极化阵列天线。阵列天线采用双层基片集成波导顺序相移馈电网络进行馈电,进一步增大了天线的圆极化带宽。综合考虑天线的-10 dB反射系数带宽、3 dB轴比带宽和3 dB增益带宽,测试结果表明,圆极化阵列天线的有效带宽为10.74-13.30 GHz(21.3%),在通带范围内最大增益为14.50 dBi。

A wideband high-gain substrate integrated cavity(SIC)circularly polarized antenna array is presented for Ku-band application.By introducing a pair of crescent-shaped patches placed at an angle along the SIC aperture and the feed slot at the bottom of the SIC,the high-order modes TM_(211) and TM_(121) in the SIC are adjusted to have the same amplitude and a phase difference of 90°,and realize high-gain circularly polarized radiation.Meanwhile,the dual parasitic patches also introduce a cavity-backed slot-coupled dipole circularly polarized radiation,which broadens the antenna circularly polarized radiation bandwidth.On this basis,a 2×2 sequential-rotation SIC antenna array is designed with a compact double-layer SIW sequential-phase feeding network.The measured results show that the proposed antenna array has an overlaid bandwidth of 21.30% from 10.74 GHz to 13.30 GHz while considering the -10 dB reflection coefficient,3 dB axial ratio,and 3 dB gain bandwidth properties,and a measured gain of up to 14.50 dBi.