DOA estimation of closely-spaced and spectrally-overlapped sources using a STFT-based MUSIC algorithm

DOA Estimation of Multiple LFM Sources Using a STFT-based and FBSS-based MUSIC Algorithm

“…In order to relax these limitations, this paper presents the STFT-FBSS-MUSIC algorithm based on the FBSS technique [37]. The proposed algorithm uses the STFT as the t-f analysis tool, which effectively prevents the influence of the cross-terms and owns a pretty low computational complexity [35]. The proposed algorithm can work in the case of selecting the single-source t-f points or multiple-source t-f points.…”

“…In order to improve the accuracy of the DOA estimation and eliminate the influence of the cross-terms as much as possible, the existing t-f based DOA estimation algorithms generally need to select the auto-term location of the sources [18], [20], [25], [27], [30] and the single-source t-f points [26], [28], [29], [35], however, if the incident LFM sources are t-f largely joint or completely joint (coherent), the single-source t-f points are very difficult to be selected or cannot be selected, which makes it more difficult for estimating the DOAs of these LFM sources. In order to relax these limitations, this paper presents the STFT-FBSS-MUSIC algorithm based on the FBSS technique [37].…”

“…In contrast, if we select the single-source t-f points, M times feature decomposition and MUSIC spectrum search need to be carried out. In the case of t-f tiny joint or t-f disjoint LFM sources, the proposed algorithm also can select the single-source t-f points to estimate DOAs of the sources, however, the estimation accuracy is lower than that of the STFT-MUSIC algorithm [35]. This is because the FBSS technique uses the dimension decrease algorithm to solve the problem of rank loss in the STFD matrix caused by the multiple-source t-f points, which brings about the loss of the array aperture and the declines in the estimation performance of the algorithm.…”

“…In this paper, however, we only consider averaging over multiple t-f points. Assuming a group of t-f points in the t-f plane are determined, the averaged STFD matrix are obtained by [35] …”

“…Under this scenario, auto-terms t-f points [18], [20], [25], [27], [30] or cross-terms t-f points [19] have been considered to construct STFD matrices. Due to the computational complexity and the cross-terms of quadratic t-f analysis tools, the linear t-f analysis tools, e.g., the fractional Fourier transform (FRFT) [10], [13], [15], [16], [32] and the short-time Fourier transform (STFT) [33][34][35], also have been applied to the DOA estimation field. These algorithms also use the above two assumptions, which means they all cannot resolve the t-f completely or largely joint sources (the t-f points of the sources are all the same or the sources have a lot of the same t-f points), which limits their further developments.…”