IAA Spectral Estimation: Fast Implementation Using the Gohberg–Semencul Factorization
Dept. of Electr. & Comput. Eng., Univ. of Florida, Gainesville, FL, USAIEEE Transactions on Signal Processing (Impact Factor: 2.79). 08/2011; 59(7):3251 - 3261. DOI: 10.1109/TSP.2011.2131136
We consider fast implementations of the weighted least-squares based iterative adaptive approach (IAA) for one-dimensional (1-D) and two-dimensional (2-D) spectral estimation of uniformly sampled data. IAA is a robust, user parameter-free and nonparametric adaptive algorithm that can work with a single data sequence or snapshot. Compared to the conventional periodogram, IAA can be used to significantly increase the resolution and suppress the sidelobe levels. However, due to its high computational complexity, IAA can only be used in applications involving small-sized data. We present herein novel fast implementations of IAA using the Gohberg-Semencul (G-S)-type factorization of the IAA covariance matrices. By exploiting the Toeplitz structure of the said matrices, we are able to reduce the computational cost by at least two orders of magnitudes even for moderate data sizes.
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- "Literatures have also presence of certain unique attempts to perform spectral estimation. Adoption of Gohberg factorization technique was seen in the literature of Xue et al. , where the authors have used weighted least squared approach of iterative nature. The outcome of the study was analyzed using computational time as well as signal power, but the outcome of the study was not found to analyze with respect to the power spectral density, which is also one of the significant performance parameters to showcase the effectiveness of spectral estimation techniques. "
ABSTRACT: There are various applications on signal processing that is highly dependent on preciseness and accuracy of the outcomes in spectrum of signals. Hence, from the past two decades the research community has recognized the benefits, significance, as well as associated problems in carrying out a model for spectral estimation. While in-depth investigation of the existing literatures shows that there are various attempts by the researchers to solve the issues associated with spectral estimations, where majority of teh research work is inclined towards addressing problems associated with Capon and APES techniques of spectral analysis. Therefore, this paper introduces a very simple technique towards resolving the issues of Capon and APES techniques. The outcome of the study was analyzed using correlational factor and power spectral density to find the proposed system offers better spectral estimations compared to existing system.
- "The basic idea of the recently developed IAA algorithm tries to solve (5) by minimizing the following weighted least-squares (LS) cost function          min∥x−γ k;i vðf d;k ; f s;i Þ∥ "
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- "First, though, the covariance matrix˜R N is estimated using the IAA as described by (16) and (17), which can efficiently implemented without the need of direct estimation of the covariance matrix and its inverse. This can be accomplished using the celebrated Levinson-Durbin (LD) algorithm and some fast techniques for the evaluation of trigonometric polynomials related to structured matrices as detailed in , . "
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