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

Abstract

Recently, several array radar structures combined with sub-Nyquist techniques and corresponding algorithms have been extensively studied. Carrier frequency and direction-ofarrival (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 multicoset 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 2M B is sufficient to identify K ≤ Q − 1 narrowband signals of maximum bandwidth B inside. The effectiveness and performance of the estimation algorithm together with the augmenting method have been verified by simulations.

A Sub-Nyquist Uniform Linear Array Receiver Design

“…The work presented in this article is in the category of Joint AOA and frequency estimation using sub-Nyquist sampling. The major difference between the proposed architecture and previously proposed methods [12][13][14][15][16][17] is that the previously proposed methods achieve sub-Nyquist sampling by introducing extra delay in each channel and the delay needs to be accurately controlled to guarantee desired performance. In these implementations, the phase difference caused by spacing of antenna array and extra delay in each channel is used to estimate both signal AOA and frequency.…”