Direction finding with a uniform circular array via single snapshot processing

Koc, AT
Tanik, Y
In this work a new algorithm for multiple emitter direction finding by using a uniform circular array is proposed. The algorithm is based on single snapshot processing, and therefore, it has no restriction on the coherency of the sources. The problem formulation is based on the transformation of the snapshot. The transformed sequence is formed by taking the discrete Fourier transform of the snapshot and weighting it suitably. It contains the so-called distortion terms, which are taken into account by using an iterative correction scheme to improve the estimation accuracy. The convergence is achieved in a few steps, and a significant performance improvement is observed when the distortion terms are taken into account. The proposed bearing estimation algorithm is based on the linear prediction method developed in this study, in which the prediction filter coefficients are found by replacing the weighted data matrix by a specified rank approximation, which is obtained by its singular-value decomposition. The direction of arrival estimates are obtained from the angular locations of the prediction-error filter zeros. It is observed through computer simulations that the algorithm performance is improved as compared to that of the forward-backward linear prediction (FBLP) and the modified FBLP methods by choosing an appropriate rank for the approximating matrix. The root-mean-square errors are close to the Cramer-Rao bounds in most cases, where the aforementioned methods fail to work. (C) 1997 Elsevier Science B.V.


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In this work, a new algorithm for multiple emitter direction finding by using a single antenna moving along a circular trajectory is proposed. The problem is formulated by taking the Doppler frequency shift, caused by the movement of the antenna. into account, and by assuming that the information, hidden in the incoming signals, does not change in the observation duration. The proposed direction finding algorithm is, therefore, based on single snapshot processing and also on the linear prediction method dev...
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In this paper, single snapshot direction-of-arrival (DOA) estimation under mutual coupling (MC) is considered for arbitrary array structures. A compressed sensing approach is utilized and a joint-sparse recovery algorithm is proposed for DOA and MC coefficient estimation. In this respect, both spatial source directions and MC coefficients are embedded into a joint-sparse vector. A new dictionary matrix is defined using the symmetricity of the MC matrix. The proposed approach does not depend on the structure...
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[1] A new approach is proposed for DOA estimation in nonuniform linear arrays (NLA) based on array interpolation. A Wiener formulation is presented to improve the condition number of the mapping matrix as well as the performance for noisy observations. Noniterative and iterative methods for DOA estimation are proposed. These methods use an initial DOA which is then significantly improved by the subsequent processing. Partially augmentable nonredundant arrays (PANA) and partly filled NLA (PFNLA) are consider...
Citation Formats
A. Koc and Y. Tanik, “Direction finding with a uniform circular array via single snapshot processing,” SIGNAL PROCESSING, pp. 17–31, 1997, Accessed: 00, 2020. [Online]. Available: