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对于运动复杂的舰船目标，基于距离-多普勒(RD)原理的ISAR成像方法和基于魏格纳-维尔分布(WVD)等传统时频分布的ISAR成像方法已经不能满足要求。应寻找具有高交叉项抑制能力同时保持较高时频聚集性的新时频分布用于ISAR舰船成像。本文研究了两种时频分布马根诺-希尔谱图分布(MHSD)和乔伊-威廉斯分布(CWD)在舰船目标 ISAR 成像中的应用。通过计算回波数据的 MHSD和 CWD，得到不同时刻的高分辨瞬时多普勒谱，然后对观测数据段的不同时刻进行瞬时成像。仿真信号实验证明MHSD拥有极好的交叉项抑制能力， CWD在选取合适的参数的情况下也有较好的交叉项抑制能力，二者均具有较好时频聚集性。ISAR舰船实测数据成像结果验证了基于MHSD和CWD成像方法的有效性，得到了舰船目标清晰的瞬态像。“,”ISAR imaging method based on Range-Doppler (RD) theory and conventional time-frequency distribution such as Wigner-Ville Distribution can not be satisfactory to the ship targets due to the complexity of its movement. New kinds of time-frequency distributions which have good time-frequency concentration is needed for ISAR ship imaging. In this paper the application of two kinds of time-frequency distribution-the Margenau-Hill Spectrogram Distribution (MHSD) and the Choi-Williams Distribution (CWD) in ISAR imaging spectrum at ship target is studied. The high resolution instantaneous Doppler frequency spectrum at different times is obtained by processing the radar echo data with the MHSD and the CWD, and then the instantaneous ISAR images from different times are obtained. It is proved by the simulation signal results that the MHSD has very good cross-term reduce property. The CWD may have good cross-term reduce property when its parameters are suitably selected. The MHSD and the CWD both have high time-frequency concentration. Result of ISAR real data of ship show the validity of the imaging method based on MHSD and CWD. Clear instantaneous images of ship target are obtained.