小波域HMT模型去噪对干涉图解缠的影响

Obtaining a digital elevation model (DEM) with the help of synthetic aperture radar interferometry (InSAR) requires interferogram unwrapping known to be sensitive to noise. Especially the existence of many noises slows down the convergence of typicall unwrapping algorithms and introduces errors into the computed results, affecting the accuracy of DEM. In order to reduce the effect of noises to interferogram, a noise filtering step must be performed. SAR interferograms filtering using wavelet-domain hidden markov tree (HMT) model is studied. This suggests applying the wavelet-domain hidden markov tree (HMT) model denoising technique with the interferogram as input. The result shows that the new method is powerful to interferogram speckle noise suppression and residues reduction, as well as it can improve the accuracy of unwrapping.