准光学馈电系统设计与分析

针对遥感卫星对于多频段、多极化探测的应用需求，设计了一套毫米波辐射计天线前端准光学馈电系统，可以实现54 GHz和183 GHz两个频段、H/V双线极化、4个通道同时接收电磁辐射信号，完成地球大气温湿度的有效探测。通过对馈电网络进行仿真建模和分析计算，可以验证馈电系统的输出参数完全满足设计指标要求，最后通过对原理样机各通道远场辐射参数的实验测试，包括照射半张角、交叉极化水平、波束效率等，测试与仿真结果一致，有效地验证了准光学馈电系统设计方案的合理性与可行性。

Design and analysis of the quasi-optical feed system

Aiming at the application of remote sensing satellite for multi-band and multi-polarization detection, a quasi-optical feed system which is the important device of millimeter-wave radiometer antenna on satellite is designed. This feed system can respectively receive the electromagnetic signals at 54 GHz and 183 GHz to complete the effective detection of earth atmospheric and humidity. Each frequency band has H/V polarization. The quasi-optical feed system is constructed and simulated. The simulated results can meet the requirements on antenna system. The far-field radiation parameters of prototype, like taper angle, cross-polarization, beam efficiency, are measured. The measured results demonstrate that the proposed feed-system has a good performance and its feasibility and rationality are verified.