采用阵列天线的微波成像系统会产生多通道幅相不一致性问题.针对使用阵列天线进行微波成像的应用,将回波模型中的多通道相位误差分为距离偏移误差和残余常数相位误差,并分析其对成像造成的影响,研究了使用回波中选定参考点目标进行相位误差校正的方法.最后通过微波成像国家重点实验室开发的地基实验系统数据验证了我们的分析和结论.
The problem of multi-channel amplitude and phase incongruity occurs when array antennas are used in a microwave imaging system. We divide multi-channel phase errors into two categories: the range deviation error and residue constant phase error. The effect of each category of error on imaging is analyzed and a calibration method using strong scattering point calibrator is proposed. All of our analyses and conclusions are verified by the experiments in the ground-based system developed in the National Key Laboratory of Microwave Imaging Technology.
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