Micro-doppler interference removal via histogram analysis in time-frequency domain

Micro-Doppler interference generated by mechanical vibration or rotation of a target or its parts may degrade the quality of radar images. In this paper, a method based on histogram analysis of the time-frequency distribution is proposed for enhanced radar image reconstruction with effective micro-Doppler interference removal. First, based on the different frequencies of occurrence between the micro-Doppler and rigid-body components as revealed in the time-frequency analysis, the rigid-body data contaminated by micro-Doppler components are removed at each frequency bin. Then, the full data set is restored based on the data preserved in the first step. Finally, the radar image is reconstructed by using the preserved and restored data rendered from the previous two steps. Experimental results show that compared with the recently developed L-statistics-based method, the proposed method offers better micro-Doppler interference removal capability and, thereby, enhances the reconstructed radar images with higher peak-sidelobe ratio and integrated sidelobe ratio.