Parameter Estimation for Space Precession Targets With Intermittent Observation

Parameter estimation of micro-motion is essential to the feature extraction for uncooperative targets. Precession is a common form of micro-motion for space targets. However, the existing estimation methods for precession parameter need a long-term continuous observation causing a large consumption of radar system resources. Intermittent observation can improve the detection efficiency. Nevertheless, if the echo signal is discontinuous, the range variation caused by nutation motion will severely challenge the usability of parameter estimation methods that are based on pure precession conditions. Therefore, this letter puts forward a novel parameter estimation algorithm for precession targets with intermittent observation. First, the correlation method of echo signal's envelope is employed to estimate the coning frequency and self-spinning frequency. Second, trigonometric function transformation is adopted for the phase unwrapping of discontinuous echo signal. Third, matching pursuit and 1-D search are applied to the reconstruction of sliding scattering center's range history. Finally, effective estimation of precession parameter is realized based on a two-view range history analysis. The proposed algorithm is verified by the experiment that is based on the electromagnetic analysis data.