Sparse Doppler-only snapshot imaging for space debris

In this paper, we develop a sparse Doppler-only snapshot imaging (SDOSI) method for spinning space debris with a size of 1–10 cm which can provide a high-resolution map of the spatial distribution of the scatterers on the target. The SDOSI method deals with the Doppler imaging by solving a sparse signal reconstruction problem. The basis dictionary of the signal is constructed according to the prior moving information of the debris and the spinning target return model, and the reconstruction is implemented by an effective greedy method named regularized orthogonal matching pursuit (ROMP). Furthermore, the proposed method is able to image the debris when the radar pulse repetition frequency is less than twice the Doppler bandwidth of the return signal and the shadowing effect is present. Finally, the performance of the new method is evaluated by both theoretical analysis and simulation results.

► We develop a sparse Doppler-only snapshot imaging (SDOSI) method for spinning space debris. ► The Doppler imaging problem can be converted to a sparse reconstruction problem. ► The spinning target return model is applied to construct a redundant dictionary. ► Regularized orthogonal matching pursuit is served as a solver of the reconstruction problem. ► The SDOSI can resist Doppler spectrum alias and alleviate the shadowing effect.