基于带状线形式的宽带Rotman透镜设计

Design of Broad Bandwidth Rotman Lens Based on Stripline

针对宽带多波束网络的需求,设计了一个32天线端口,24波束端口,扫描±45°基于带状线形式的Rotman透镜。通过全场仿真计算,分析了透镜波束端口到阵列之间S参数的幅度、时延特性,并据此计算了Rotman透镜的各个波束在不同频率的方向图。通过波束计算分析,发现基于微带形式的Rotman透镜相对于基于带状线形式的Rotman透镜在超宽带工作时有明显的色散效应。按照所做的基于带状线的透镜设计,制作了Rotman透镜测试样机。通过对样机的端口间幅度相位性能测试,对比分析了仿真和测试结果,验证了设计的Rotman透镜的超宽带波束扫描性能。

Aiming to the requirement of broad bandwidth multiple-beams forming,a Rotman lens with 32 element ports and 24 beam ports is designed,which is based on stripline and supports scanning angle from+45°to-45°.Based on the field simulation,the amplitude and time-delay characteristics are analyzed and the beam pattern of different frequencies for all beam ports is simulated.According to the beam analysis,we find the Rotman lens based on microstrip shows larger beam dispersion effect comparing to Rotman lens based on stripline.According to the design,a prototype is produced and the S parameters between element ports and beam ports is tested.By analyzing the simulation and test result,the designed broad bandwidth multiple-beams Rotman lens is verified.