Phase Adjustment for Extraction of Micro-Motion Information of Ballistic Targets

Micro-motion features are critical to the recognition of ballistic targets since these targets may be similar in appearances, sizes, and electromagnetic properties. The micro-motion information can be extracted by the Doppler analysis of the radar echoes. However, the existing studies mainly concentrate on the extraction of the micro-Doppler information and pay little attention to translation compensation, which is indispensable for their extractions. In this paper, a method based on the minimization of the entropy of the Doppler spectrum is proposed to accomplish translation compensation. This method works even if the Pulse Repetition Frequency(PRF) is less than the bandwidth of the Doppler spectrum. Moreover, this method can be simply implemented because entropy can be easily calculated even for wrapped spectrum. The results show that the translational Doppler phase can be well removed with this algorithm.