Optimization-Based Discontinuous Observation Strategy for Micro-Doppler Signature Extraction of Space Cone Targets

In order to obtain relatively complete micro-Doppler (m-D) signatures of space precession cone targets, at least one precession period of dwell time is always required. In practice, most of the space cone targets do precession with a relativity low frequency (i.e., 0.5-1 Hz), which means second-level dwell time is necessary. However, second-level dwell time is prohibitive in terms of radar resource consumption, especially as radar has to face the challenges of multi-targets and multi-tasks. To tackle this problem, we conduct m-D signature extraction based on a discontinuous-observation-based strategy named multi-short-dwell observation (MSDO). Specifically, by incorporating the time-frequency information, the extraction Cramér-Rao bounds give reliable bounds for the performance of the m-D signature extraction. Therefore, they are derived and used as optimization criterions for optimizing the time parameters involved in the MSDO. A cost function is established to minimize the time resource occupation ratio such that the extraction precision requirement is met. The m-D signature extraction is implemented based on the optimized MSDO parameters in which the real sinusoid estimator and the least square estimator are adopted. The simulation results illuminate the effectiveness of the proposed method.