To improve the imaging quality of a Fourier Telescopy (FT) and to implement the high-resolution imaging for moving targets, the data processing methods to inhibit the spectral leakage generated by the frequency shift error from an acousto-optic frequency shifter, the bias of an optical device and truncating signals were researched and how to calculate the signal frequency in real time was given. Firstly, an all phase spectrum analysis technology was used to process sampling signals of a static target and a search algorithm was taken to capture the maximum frequency value of each interferomet-ric beam. Then, the actual frequencies of any two beams were calculated by an all phase time shift phase difference correcting spectrum method. Finally, the frequency deviation and demodulated target 's Fourier information were obtained and the demodulation frequency of the non-whole point was estimated by the least square fitting. The results show that the Strehl ratio of reconstructed image by proposed method is increased by 3% as compared with that of traditional methods. Furthermore, the new method has a higher inhibiting ability for spectral leakage, better reconstructed image, and it can provide the reference for data processing of moving targets.%为了提高傅里叶望远镜(FT)的成像质量,实现对运动目标的高分辨率成像,研究了能抑制由声光移频器移频误差、光学器件偏差及信号采样截断等产生的频谱泄漏且能实时计算信号频率的数据处理方法.首先,采用全相位预处理技术对外场静态目标的采样信号进行处理;通过搜索算法得到每束干涉光的整点频率最大值.然后,基于apFFT谱分析时移相位差校正法计算每束干涉光的真实频率.最后,对非整点频率解调,采用5点最小二乘拟合方法,得到目标的傅里叶分量信息.实验结果表明:与传统方法相比,本文提出的数据处理方法得到的重构图像的斯托里尔比(Strehl)相应提高了3％.另外,本文方法对频谱泄漏的抑制能力更强;对静态目标实验数据进行处理后,重构图像质量有一定的提升;该方法也为运动目标的成像数据处理提供了参考.
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