球面近场下相控阵天线口径诊断研究

Research on phase array antenna diagnosing method at spherical near-field measurement

在近场测量系统中,天线口径诊断是其中一项重要功能,它能够帮助天线设计师发现相控阵天线设计或者网络配置问题.平面近场中的口径诊断技术已经广泛地应用在雷达天线测试中,在球面近场测量中同样需要这种算法.本文基于球面坐标系下电磁场模式方法,得到球面近场条件下的口径反演算法.在仿真模型中计算得到了被测天线的口径场分布,计算结果与理论模型结果吻合.对X波段阵列天线进行了实际测试,得到了不同配置下的阵列天线口径反演结果,经过数据比对,证明了本文算法的幅度反演精度优于1 dB.

Antenna hologram diagnosing is an important feature at near-field measurement system that can help antenna designer find out the problem in antenna design or antenna network configuration.Hologram diagnosing at planner near-field measurement is widely used in radar antenna measurement,in spherical near-field measurement there is also needed.Based on the electromagnetic mode expansion method under the spherical coordinate system,this paper calculates the hologram inversion algorithm under spherical near-field conditions.Then,the aperture distribution of the antenna is calculated in the simulation model,and the calculation results are consistent with the theoretical model.In the actual test,the X-band array antenna is tested,and the aperture inversion results of the array antenna under different configurations are obtained,and the amplitude inversion accuracy of the algorithm is better than 1 dB.