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arXiv · 1810.11390

Joint Estimation of DOA and Frequency with Sub-Nyquist Sampling in a Binary Array Radar System

Zhan Zhang·Ping Wei·Lijuan Deng·Huaguo Zhang
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Abstract

Recently, several array radar structures combined with sub-Nyquist techniques and corresponding algorithms have been extensively studied. Carrier frequency and direction-of-arrival (DOA) estimations of multiple narrow-band signals received by array radars at the sub-Nyquist rates are considered in this paper. We propose a new sub-Nyquist array radar architecture (a binary array radar separately connected to a multi-coset structure with M branches) and an efficient joint estimation algorithm which can match frequencies up with corresponding DOAs. We further come up with a delay pattern augmenting method, by which the capability of the number of identifiable signals can increase from M-1 to Q-1 (Q is extended degrees of freedom). We further conclude that the minimum total sampling rate 2MB is sufficient to identify $ {K \leq Q-1}$ narrow-band signals of maximum bandwidth $B$ inside. The effectiveness and performance of the estimation algorithm together with the augmenting method have been verified by simulations.

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Zhan Zhang, Ping Wei, Lijuan Deng, Huaguo Zhang. 2018-10-26. Joint Estimation of DOA and Frequency with Sub-Nyquist Sampling in a Binary Array Radar System. https://arxiv.org/abs/1810.11390

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