Motion information aided envelope alignment of HRR profiles

Envelope alignment is important for ISAR imaging of moving target. If the target scattering characteristics scintillates during the coherent processing interval (CPI), jumping errors may occur in envelop alignment based on maximum-correlation, which will lead to unexpected envelope migration. With the exploitation of target motion information, a new method is proposed to eliminate jumping errors. In detail, the migration values obtained by conventional maximum correlation are considered as measured data. Meanwhile, the target motion is described by linear model for the prediction and correction of envelope migration. Therefore, the measured data and predicted information are fused by regularization method to provide precise estimate of envelope migration. The results based on real measured data show that the proposed algorithm can effectively eliminate jumping errors and improve the performance of envelope alignment.