An Improved Toeplitz Approximation Method for Coherent DOA Estimation in Impulsive Noise Environments

Abstract

Direction of arrival (DOA) estimation is an important research topic in array signal processing and widely applied in practical engineering. However, when signal sources are highly correlated or coherent, conventional subspace-based DOA estimation algorithms will perform poorly due to the rank deficiency in the received data covariance matrix. Moreover, conventional DOA estimation algorithms are usually developed under Gaussian-distributed background noise, which will deteriorate significantly in impulsive noise environments. In this paper, a novel method is presented to estimate the DOA of coherent signals in impulsive noise environments. A novel correntropy-based generalized covariance (CEGC) operator is defined and proof of boundedness is given to ensure the effectiveness of the proposed method in impulsive noise environments. Furthermore, an improved Toeplitz approximation method combined CEGC operator is proposed to estimate the DOA of coherent sources. Compared to other existing algorithms, the proposed method can avoid array aperture loss and perform more effectively, even in cases of intense impulsive noise and low snapshot numbers. Finally, comprehensive Monte-Carlo simulations are performed to verify the superiority of the proposed method under various impulsive noise conditions.

Direction of Arrival Estimation Method Based on Eigenvalues and Eigenvectors for Coherent Signals in Impulsive Noise

“…In this section, the proposed algorithms were compared to the algorithms proposed in the Ref. [17]. In this simulation, K = 200, α = 1.1, and GSNR = 10.…”

“…To solve the DOA estimation of coherent signals, some related algorithms [17,25,26] based on correntropy were proposed. In this section, the proposed algorithms were compared to the algorithms proposed in the Ref.…”

“…For the estimation of coherent signals, researchers have proposed many methods. These are mainly divided into two categories, one of which realizes the decoherence of the signal by constructing the Toeplitz matrix [15][16][17], and the other uses the spatial smoothing method (SS) [18][19][20][21]. The Toeplitz matrix is constructed by considering the uniform linear array (ULA) as a symmetric matrix [15], which imposes specific requirements on the number of array elements.…”

“…Moreover, the two methods described above do not take the influence of noise into account. A novel method based on correntropy-based generalized covariance (CEGC) is proposed to construct a Toeplitz matrix [17]. However, it does not take full advantage of the properties of the reception correlation matrix itself because the generation of a Toeplitz matrix involves the diagonal summation of all elements across the matrix, followed by average summation.…”

A Novel DOA Estimation Algorithm Based on Robust Mixed Fractional Lower-Order Correntropy in Impulsive Noise

“…Although this method notably enhances accuracy and robustness, its real-time applicability may be hampered by considerable computational demands. In [32], Dai presented an enhanced Toeplitz approximation method incorporating a correntropy-based generalized covariance (CEGC) operator. While boasting high resolution and sidestepping array aperture loss, the method might struggle with substantial computational complexity in expansive scenarios.…”