Improved signal enhancement procedures applied to exponential data modeling

Various signal enhancement techniques have been proposed to improve spectral estimation of closely spaced sinusoids in the presence of noise. This correspondence exploits the filtering interpretation of some well-known SVD-based iterative algorithms for signal enhancement to further improve their performance. It is shown that the initial conditions that are used throughout the filtering process may considerably affect the spectral characteristics of the signal. A strategy is proposed to minimize these undesirable effects. The new method improves the performance of fully automated magnetic resonance spectroscopy (MRS) quantitation.