Abstract: Phase unwrapping is one of the most important cases in PS-DInSAR.As it is similar with the GPS ambiguity resolution,the process to solve the ambiguities and deformation parameters by the algorithm of LAMBDA is presented based on the function models of PS-DInSAR.Two algorithms of LLL and inverse integer Cholesky are applied to decorrelate,which is the also named as z transformation in LAMBDA.With the criterions of iterative numbers of z transformation,condition number of variance-covariance matrix and mean correlation coefficient of ambiguity vectors,the performance of two algorithms are compared by random numerical simulation.The results show that the modified algorithm of LLL is equal to inverse integer Cholesky algorithm.The interpretation to the equality is given in theory.