一种具有高隔离度的双频双圆极化卫星通信天线

 提出了一种新型的用于卫星通信的双频双圆极化多层微带贴片天线.该天线采用兰格耦合器正交馈电,分别在420±1.5MHz和450MHz±1.5MH的收发频率实现右旋和左旋圆极化辐射,且满足单一天线收发双工的通信要求;采用耦合贴片馈电方式和附加集总电路滤波网络,有效地改善了两端口之间的收发隔离度.此外,该天线采用高介电常数的介质基板减小了天线尺寸.兰格耦合器采用曲折线技术减小了馈电网络的结构尺寸(约74.6%).仿真和实测结果吻合良好,在工作频带内收发隔离度大于40dB,VSWR小于2.0,增益大于3dBc,0dB增益宽度及3dB轴比宽度均达到80°.

Dual Frequency and Dual Circular Polarization Antenna with High Isolation for Satellite Communication

A novel dual frequency and dual circular polarization mulfilayer microstrip antenna for satellite communication is presented. The proposed antenna can realize right circularly polarized radiation and left circularly polarized radiation simultaneously at 420±1.5MHz and 450MHz±1.5MH by using the Lange-coupler as an orthogonal feeding network.And,the duplex communi-cation is achieved for the single antenna. The patch coupled feeding and additional lumped filtering network improve isolation effec-tively.In addition,the antenna is constructed with high permittivity dielectric substrate, which can help to reduce the antenna size. The Lange-eonpler size is miniaturized (about 74.6%) with the meander-line structure. A good agreement is achieved between the simulation and the experiment results. In the operating frequency band, the isolation is more than 40dB, VSWR is less than 2.0 and the radiation gain of the proposed antenna is larger than 3dBc. The measured results show that both of the 3 dB axial ratio and the 0 dB gain width reach up to 80 degrees.