一种S频段卫星通信相控阵天线设计

为了解决目前卫星通信相控阵天线波束扫描角度范围较小、低仰角增益较低等问题，采用双层微带结构，加载圆形金属腔体，实现了更宽波束的S频段圆极化相控阵单元，来提高相控阵低仰角增益．然后，用24个单元按照水滴状形式排布组成相控阵阵列，以减小风阻．仿真结果表明，在收发频段内，相控阵单元的电压驻波比小于1.3，轴比小于3dB，单元在阵中的3dB波瓣宽度为120°左右; 天线阵列在扫描到仰角25°时，其增益相比天顶方向(仰角90°)下降了4dB左右．最后，加工好的天线阵列测试结果和仿真结果具有很好的一致性，波束扫描角度较宽，低仰角增益较大，满足设计要求．

Design of a satellite communication phased array antenna in the S-band

The phased array antenna for satellite communication has a smaller beam-scanning angel and a lower gain at the low elevation angel at present. A circularly polarized (CP) antenna element with a wide beam-width in the S-band is proposed. To enhance the realized gain at a low elevation angel, this element is adopted with the dual-layer micro-strip structure and loads a circular metal cavity. Based on the element, a phased array antenna composed of 24 antenna units is designed, which has a water-drop form to reduce wind resistance. The simulated results show that over the transmitting and the receiving frequency band, the voltage standing wave ratio (VSWR) of this element is less than 1.3, that the axial ratio (AR) is less than 3dB, and that 3dB beam-width of the element is about 120° in the array; the realized gain of the array is declined about 4dB when the scanning angle is approaching 65°. Later, the measured results of the manufactured array antenna present a good consistency with the simulated results. It possesses a wide scanning angle and a high realized gain at low elevation angel, which satisfies the design requirement.