Due to the sparsity of inverse synthetic aperture imaging lidar (ISAIL) echoes in range-Doppler (R-D) plane
a phase adjustment algorithm for ISAIL is proposed.The sparsity is used as a global constraint condition for phase adjustment
then the regularization method is brought in to solve this optimization problem.Hadamard multiplication and fast Fourier transform are applied to improve the computation efficiency.Compared with the traditional ISAIL imaging algorithm
image of target is well focused by our method under the condition of low SNR or lack of echoes.The ISAIL imaging experiments with numerical and measured data validate the feasibility and effectiveness of the proposed algorithm.