In this study, the applicability of adaptive filters and algorithms to the enhancement of Raman spectra is investigated. The two adaptive-filter realizations described are the transversal (tapped-delay) and the lattice. The two adaptive algorithms considered are the least-mean-square and the modified least-square. Experimental results demonstrate that enhancement of Raman spectra obtained at low signal-to-noise ratios can be achieved. Extrapolation is applied to enhance the inherently low resolution of Raman spectra. Adaptive filtering techniques yield results comparable to those obtained from maximum-entropy methods for estimating spectra, with a resolution exceeding that allowed by Fourier procedures.
Ramiro Jordan and Stephen A. Dyer, "Adaptive Signal Processing Techniques: An Application to Raman Spectroscopy," Appl. Spectrosc. 43, 750-758 (1989)