Micromotion is an important target feature,although the target micromotion has an unfavorable influence on the synthetic aperture radar (SAR) image interpretation due to defocusing.This paper introduces micromotion parameters into the scattering center model to obtain a hybrid micromotion-scattering center model,and then proposes an optimization algorithm based on the maximal likelihood estimation to solve the model for jointly obtaining target motion and scattering parameters.Initial value estimation methods using targets’ghost images are then presented to guarantee the global and fast convergence.Simulation results show the effectiveness of the proposed algorithm especially in high precision estimation and multiple targets processing.
Micromotion is an important target feature, although the target micromotion has an unfavorable influence on the synthetic aperture radar (SAR) image interpretation due to defocusing. This paper introduces micromotion parameters into the scattering center model to obtain a hybrid micromotion-scattering center model, and then proposes an optimization algorithm based on the maximal likelihood estimation to solve the model for jointly obtaining target motion and scattering parameters. Initial value estimation methods using targets' ghost images are then presented to guarantee the global and fast convergence. Simulation results show the effectiveness of the proposed algorithm especially in high precision estimation and multiple targets processing.