Sequential Estimation of Frequency and Direction-of-Arrival Based on the Relaxed Coprime Array for Multiple Targets

Abstract

Recently, extensive researches focus on the joint estimation of carrier frequency and directionof-arrival, whereas the heavy computation burden and affordable hardware cost are always required therein. To alleviate the problem, we propose a relaxed coprime array based two-stage estimator, which can sequentially detect the frequencies and direction-of-arrival for multiple targets. Guided by the closed-form robust algorithm, this relaxation yields a higher array sparsity compared with existing sparse arrays. Specifically, the first stage aims to achieve the classification of the frequency and angle remainders arising from temporal-spatial undersampling, which is realized by combining spectrum correction with pattern clustering. By incorporating the closed-form robust Chinese Remainder Theorem into the remainder classification result, we obtain all the frequencies and direction-of-arrival in the second stage. Both performance analysis and numerical results were conducted to verify the effectiveness of the proposed estimator in the multi-target case.

Joint Angle and Frequency Estimation in Linear Arrays Based on Covariance Reconstruction and ESPRIT

“…For example, in a wireless communication system, accurate and robust joint angle and frequency estimation can help provide better channel information, thereby improving the link quality and anti-interference ability of the system [1]. Especially in electronic reconnaissance [5][6][7][8], we often use the operating frequencies and directions of arrival (DOAs) [9][10][11][12][13] of noncooperative radar radiation source signals to describe the main parameters of radar signal characteristics [14][15][16].…”