多模式超高斯馈源的设计与分析

针对各类探测器高性能馈源喇叭的需求,对多模式超高斯馈源的理论进行研究,特别是对低旁瓣进行分析。采用波纹喇叭及多节喇叭技术对馈源进行设计,并用全波分析法进行仿真验证。讨论利用级联矩阵理论对多节结构进行优化分析的基本流程。基于仿真结果,综合比较了基于这2种设计技术的馈源喇叭性能的优劣。结果表明:多节结构相对传统的波纹喇叭具有结构简单、旁瓣电平无明显恶化的优势;其劣势在于由于引入多模结构,带宽仍有待提高。采用级联矩阵的优化方法可将结构与模式理论结合,是一种物理概念更加清晰的方法。该研究对于高性能超高斯喇叭的设计和加工有一定的参考价值。

Design and Analysis of Multi-Mode Super Gaussian Feed

To meet the requirements of space-qualified feed horn, the theory of multi-mode super Gaussian horn antenna is studied in this paper. An emphasis is placed on the side lobe level. The design and analysis are based on theories of corrugated horn and multi-section horn. A full-wave analysis is performed to simulate the radiation patterns. The procedure of optimization of multi-section horn using cascaded matrix analysis is presented. Based on the simulated results, a systematic comparison on the performance of the horn antennas designed by using the two techniques is presented. It is found that multi-section structure bears the benefit of easy fabrication without compromising the performance. The bandwidth of the multi-section structure, however, still needs to be improved. In addition, the cascaded matrix method links the modes and structures, enabling one to see the physics in the process of design. This work is a useful reference to the design and fabrication of high performance super Gaussian horn.