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

TL;DR

This paper introduces a novel sub-Nyquist array radar system and an efficient joint estimation algorithm for DOA and frequency, enhancing signal identification capabilities at reduced sampling rates.

Contribution

A new binary array radar architecture combined with a joint estimation algorithm and delay pattern augmentation to improve signal identification at sub-Nyquist rates.

Findings

The proposed system can identify up to Q-1 signals with a total sampling rate of 2MB.

The delay pattern augmentation increases the number of identifiable signals.

Simulations verify the effectiveness of the estimation algorithm and augmentation method.

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.