Single-lidar multi-view micro-Doppler analysis for tumbling non- cooperative space target characterization

Identifying tumbling-induced micro-Doppler signatures is critical for analyzing non-cooperative space targets. For targets undergoing complex motions, it is often difficult to reliably extract micro-motion features from single-lidar measurements, while configurations with multiple LOS directions may suffer from increased data volume and complicated processing. This paper proposes a single-lidar configuration with three LOS directions at three distinct time instants suitable for ultra-long-range detection, together with a Doppler-edge-profile-based fitting (DEPF) scheme for estimating the dimensions, tumbling axis, and tumbling frequency of a rectangular target undergoing off-axis tumbling. The proposed approach jointly processes echoes acquired at the three distinct time instants (corresponding to three different LOS directions) to fully exploit micro-Doppler information, thereby mitigating error propagation and improving robustness. Simulations and experiments demonstrate accurate estimation of the tumbling frequency, target sizes, mass-center offset, and tumbling-axis orientation. The relative errors of key scalar parameters are kept below 6%, and the tumbling-axis direction error is within 5.6°. The proposed method enables high-accuracy estimation of target micro-motion parameters at ultra-long ranges.