Phase Estimation in Multi-Baseline InSAR through Maximum Likelihood Method

s—In radar interferometry, the short baseline can produce higher altitude error; the long baseline can produce higher phase unwrapping error. Multi-baseline InSAR technique combined the respective advantages of the short and long baselines; it can produce higher DEM accuracy or obtain the surface deformation. This paper mainly studies on the phase estimation in multi-baseline InSAR through the Maximum Likelihood method, and estimates the integrated phase of three SAR images. The results show that multi-baseline data fusion can make the phase non-fuzzy interval expand to (-nπ~nπ), which can simplify the phase unwrapping process and improve the DEM accuracy.