导航终端多模宽带微带天线馈电网络设计

Design Feed Network for Multi-Mode Broadband Microstrip Antenna of Navigation Terminal

摘要: 为了满足导航终端接收四大导航系统信号提高导航服务质量的需要，本文设计实现了适用于导航终端多模宽带微带天线的四馈电网络，通过在四个端口port1~port4依次施加90度相位差等幅度激励信号获得右旋极化，提高了圆极化纯度，获得了符合设计要求的圆极化带宽。综合利用Designer和HFSS软件场路协同仿真表明：该天线在四个导航系统的频率范围内，具有良好的电性能和辐射特性，顶点轴比小于3 dB，阻抗带宽为45%，增益大于6 dB，回波损耗S11小于−10 dB，保证了多模导航中的精度需要。

Abstract: In order to meet the demand of improving navigation service quality through receiving signals from the four GNSS systems, a four-feed network is designed and implemented for the multi-mode broadband microstrip antenna of navigation terminal. The right-handed polarization is obtained by applying 90-degree phase difference and other amplitude excitation signals at the port 1 to port 4 successively, improving the purity of circular polarization, and obtaining the circular polarization bandwidth that meets the design requirements. The comprehensive simulation using Designer and HFSS software shows that the antenna has good electrical performance and radiation characteristics within the frequency range of the four navigation systems. The vertex axial ratio is less than 3 dB; the impedance bandwidth is 45%; and the gain is greater than 6 dB; and the echo loss S11 is less than −10 dB, which ensures the accuracy needed in multi-mode navigation.