To deal with the degradation of the conventional range alignment algorithm under low SNR

an ISAR (Inverse Synthetic Aperture Radar) range alignment method is proposed based on iterative weighted least squares fitting.Utilizing the stationary moving characteristic of the target

the proposed method make alternatively iterative update of both the range migration and the weighted matrix

thus realizing the range alignment based on the estimation of the parameters of the target motion.The simulation demonstrates that the proposed method can effectively restrain the transmission of the jump error and relieve the decline of the parameter estimation precision caused by the drift error

which shows a good performance in range alignment.