大张角波纹喇叭的优化设计

Optimization Design of Wide-flare-angle Corrugated Horn

针对平方公里阵(Square Kilometre Array,SKA)天线对高灵敏度的需求,利用基于旋转体时域有限差分法(BOR-FDTD)和自适应协方差矩阵进化策略(CMA-ES)的波纹喇叭优化设计技术,提出了以灵敏度为目标的大张角波纹喇叭优化设计方法。分别以天线口径效率和灵敏度为优化目标对工作于4.6~8.51 GHz的大张角波纹喇叭进行优化设计。计算结果表明,以灵敏度为优化目标所设计的波纹喇叭综合性能更优,其交叉极化和反射损耗均优于-20 d B,用于SKA天线的口径效率在85.1%以上,灵敏度优于7.68 m^2/K。

Considering the high sensitivityrequirement of the antenna for SKA,this paper presents the optimization method of corrugated horn taking the sensitivity as the optimization objective.An optimization method of corrugated horn based on BOR-FDTD and CMA-ES is used.A corrugated horn with the bandwidth from 4.6 ~ 8.51 GHz is optimized based on aperture efficiency and sensitivity optimization objectives respectively.It is found that when the optimization objective is the sensitivity,the comprehensive performance of the corrugated horn is better,the return loss and cross-polarization are less than-20 d B,the efficiency is better than 85.1% and the sensitivity is above 7.68 m^2/ K over its frequency range.