提出了一种利用线性载波对不连续相位图进行延拓后相位展开的方法。首先,通过傅里叶变换法确定载波频率;然后,用最小二乘法确定与相位图相匹配的线性载波对背景、遮拦区域进行延拓;最后,采用经典的相位展开算法对延拓后的相位图进行展开。实验结果表明,对于包含较大线性载波的不连续干涉图,延拓后相位展开结果避免了各区域间的全局误差;计算机模拟结果表明,对于包含较小线性载波或不含载波的不连续干涉图,经过线性载波调制后,使用该方法得到相位展开结果与真实波面均方根差仅为0.0021 rad,不存在全局误差。

A new phase unwrapping method to extend the discontinuous wrapped phase with linear carrier before unwrapping is presented. First,the carrier frequency is determined by the Fourier transform method. Then the least-square method is used to calculate the linear carrier which matches with the wrapped phase to extend the background and obscurations region. Finally,the classical quality-guided method is used to unwrap the extended phase map. The experiment result shows that,for the discontinuous interferograms with large linear carrier,the unwrapping result avoids the global errors between different regions. The computer simulation result shows that,the method can be applied to discontinuous interferograms with small linear carrier or without carrier and get the correct unwrapping result can be obtained after linear carrier modulation.