针对传统多基线合成孔径雷达干涉相位估计方法存在稳健性不高、适应性不强的问题,该文提出一种稳健的多基线合成孔径雷达干涉相位估计方法。利用最大似然频率估计准则从最短基线干涉图中提取每一复像元随基线变化频率的粗略估计值,并把提取的粗略频率通过共轭复乘补偿给相应的抽样复干涉信号,来降低抽样复干涉信号频率,避免了干涉基线间隔过大导致的抽样复干涉信号频谱混叠现象,从而克服了干涉基线间隔对长基线干涉相位估计精度的限制。实验结果表明,该方法不受干涉基线间隔的限制,能较为精确地获得长基线干涉相位估计值,对多基线干涉合成孔径雷达技术应用拓展以及高精度地理信息系统构建等具有参考价值。
Considering that traditional methods are not robust and adaptable,a new multi-baseline phase estimate algorithm for SAR interferometry was proposed in this paper.This method applied maximum likelihood frequency estimation principle to extract the coarse frequency of each sample complex signal from interferogram with the shortest baseline;then decreased the frequency of corresponding sample complex signals by conjugate multiplying with the coarse frequency obtained from interferogram with the shortest baseline,which could avoid spectrum aliasing phenomenon caused by the large baseline interval and remove interferometric baseline interval limit on phase estimation accuracy of interferograms with the longer interferometric baselines.The results obtained with synthetic data showed that the proposed method was not constrained by the interferometric baseline spacing and could obtain good results from interferograms with the longer baselines,which was beneficial to expand the application of multi-baseline InSAR technology and build high-precision geographic information system.