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arXiv · 1908.02929

Theoretical Analysis for Extended Target Recovery in Randomized Stepped Frequency Radars

Lei Wang·Tianyao Huang·Yimin Liu
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Abstract

Randomized Stepped Frequency Radar (RSFR) is very attractive for tasks under complex electromagnetic environment. Due to the synthetic high range resolution in RSRFs, a target usually occupies a series of range cells and is called an extended target. To reconstruct the range-Doppler information in a RSFR, previous studies based on sparse recovery mainly exploit the sparsity of the target scene but do not adequately address the extended-target characteristics, which exist in many practical applications. Block sparsity, which combines the sparsity and the target extension, better characterizes a priori knowledge of the target scene in a wideband RSFR. This paper studies the RSFR range-Doppler reconstruction problem using block sparse recovery. Particularly, we theoretically analyze the block coherence and spectral norm of the observation matrix in RSFR and build a bound on the parameters of the radar, under which the exact recovery of the range-Doppler information is guaranteed. Both simulation and field experiment results demonstrate the superiority of the block sparse recovery over conventional sparse recovery in RSFRs.

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Lei Wang, Tianyao Huang, Yimin Liu. 2019-08-08. Theoretical Analysis for Extended Target Recovery in Randomized Stepped Frequency Radars. https://doi.org/10.1109/tsp.2021.3058444

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