旋转偏馈反射面天线的赋形设计  

Shaping Design of Offset Rotated Reflector Antennas

作　　者：王璐璐[1,2] 黄文华[1,2] 章勇华 汪海波[1,2] 

机构地区：[1]西北核技术研究所,西安710024 [2]高功率微波技术重点实验室,西安710024

出　　处：《现代应用物理》2016年第3期18-23,共6页Modern Applied Physics

摘　　要：通过对抛物面赋形,设计了一种馈源固定不动、反射面俯仰方向可旋转扫描0°~10°,增益平坦度优于0.5dB的偏馈反射面天线。首先,选取抛物面上采样点作为初始数据点,进行三次样条函数插值构成初始反射面;其次,利用Matlab的Fminunc函数对插值数据点进行调整,采用几何光学法计算射线平均光程差,并用其方差最小实现优化,确定赋形反射面的形状;最后,通过电磁仿真软件计算验证了赋形天线的电性能指标。设计的反射面天线系统工作频率为9.7GHz,反射面焦距为6.8m、口径为5m、偏置高度为0.2m,馈源为20dB标准增益喇叭。计算结果显示,赋形后天线增益平坦度由1.07dB优化到0.46dB。A reflector shaping design of the paraboloid is made to achieve the gain flatness less than 0.5 dB, while the reflector is rotated from 0°- 10° in pitching direction with a fixed feed source. First, a cubic spline interpolation method is used to create the initial reflector based on the sampling points of the paraboloid. Then, the interpolation data points are adjusted by using Fminunc function in Matlab. The shaped reflector surface is obtained by calculating the average optical path difference （OPD） with the geometrical optics （GO） method, and by making the variance to be minimal to achieve the optimization objective. Finally, the shaped reflector antennas＇ electrical property is calculated in the electromagnetic simulation software. An reflector antenna system of operating frequency at 9. 7 GHz is designed with focal length of 6.8 m, diameter of 5 m, offset height of 0.2 m, and feed source of 20 dB standard gain horn. The results show that the gain flatness is decreased from 1.07 dB to 0.46 dB after optimization.

关 键 词：反射面天线 赋形设计 光程差 增益平坦度 

分 类 号：TN820.2[电子电信—信息与通信工程]