ISAR成像的相参多普勒质心跟踪相位补偿方法

摘要

目标强散射中心的转动相位分量对传统多普勒质心跟踪(DCT)相位补偿方法性能具有较大的影响.本文通过分析得出STRETCH处理得到的目标回波初相不具备相参性,而中频直接采样回波信号脉间具备相参的特点,并提出相参多普勒质心跟踪相位补偿(CDCT)方法.该方法在DCT方法的基础上,利用中频直接采样得到的目标回波的脉间相参性提高平动相位分量估计的精度,从而提高相位补偿效果,改善ISAR成像的质量.相对于MDCT法,本文能够达到更好的相位补偿效果.实测数据验证了本文方法的有效性.%Rotational phase component (RPC) of target' s prominent scattering canters may deteriorate the performance of Doppler centroid tracking (DCT) method.The non-coherent property of pulses sampled after STRETCH processing and the coherence feature of pulses sampled directly in intermediate frequency (IF) is firstly analyzed.Then by using this property,the coherent DCT phase compensation method is developed in this paper.On the basis of DCT method,the proposed approach improves the translational phase component (TPC) estimation accuracy and improves the quality of ISAR image.Compared to the modified Doppler centroid tracking (MDCT) algorithm,the proposed method achieves better phase compensation performance.Experimental results prove the effectiveness of the proposed strategy.