Compared with the Nyquist sampling scheme, the coprime sampling scheme reduces the requirement of sampling rate significantly and simultaneously shows high degrees of freedom. Actually, the information received by the...
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Compared with the Nyquist sampling scheme, the coprime sampling scheme reduces the requirement of sampling rate significantly and simultaneously shows high degrees of freedom. Actually, the information received by the sampler is not fully utilized due to the non-uniformity of derived second-order virtualcoarray. In addition, the virtual signals corresponding to the non-uniform virtualcoarray may be contaminated by noise, which could affect the accuracy of spectrum estimation. In this letter, we propose a novel virtual coarray interpolation method for the inexact Toeplitz covariance matrix based on truncated nuclear norm regularization. The missing elements and exact covariance matrix can be obtained simultaneously by solving the covariance matrix completion problem that contains the error term and non-Toeplitz errors propagation control term. Simulation results demonstrate the superiorities of the proposed spectrum estimation method in terms of accuracy and computational complexity.
For frequency estimation, the recently proposed coprime sampling scheme receives increasing interest as it reduces sampling rate and exhibits high degrees of freedom. However, the virtualcoarray generated by coprime ...
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For frequency estimation, the recently proposed coprime sampling scheme receives increasing interest as it reduces sampling rate and exhibits high degrees of freedom. However, the virtualcoarray generated by coprime configuration is a linear virtual array structure with some missing elements. This leads to information loss if only the contiguous part of the virtualcoarray is used. In this paper, we propose a new approach to fix this problem. A multi-rate coprime sampling mechanism is designed to fill all the holes in the classical coprime virtualcoarray. This is achieved by constructing new virtualcoarrays containing the hole elements which can be selected to fill all the holes in the original virtualcoarray. Furthermore, by properly setting the multi-rate coefficients to positive integers, our approach allows to reuse some samples obtained with the classical coprime sampling configuration. The closed-form expression of the positions of the holes is also given, which can be used to choose the appropriate multi-rate coefficients. Simulation results show that the proposed approach can increase the degrees of freedom without requiring additional samples. The estimation accuracy is also improved because our proposed approach fully exploits the information from the available samples. (C) 2019 Elsevier B.V. All rights reserved.
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