Title :
All-pole modeling technique based on weighted sum of LSP polynomials
Author :
Bäckström, Tom ; Alku, Paavo
Author_Institution :
Lab. of Acoust. & Audio Signal Process., Helsinki Univ. of Technol., Espoo, Finland
fDate :
6/1/2003 12:00:00 AM
Abstract :
This study presents a new technique called weighted-sum line spectrum pair (WLSP) where an all-pole filter is defined by using a sum of weighted line spectrum pair polynomials. The WLSP yields a stable all-pole filter of order m, whose autocorrelation function coincides with that of the input signal between indices 0 and m-1. By sacrificing the exact matching at index m, the WLSP models the autocorrelation of the input signal at the indices above m more accurately than conventional linear prediction (LP). Experiments with vowels show that, in comparison to the conventional LP, WLSP yields all-pole spectra that model formants with an increased dynamic range between formant peaks and spectral valleys.
Keywords :
correlation methods; data compression; filtering theory; linear predictive coding; poles and zeros; polynomials; spectral analysis; speech coding; LSP polynomials; WLSP; all-pole modeling; all-pole spectra; autocorrelation function; dynamic range; formant peaks; formants; input signal; linear prediction; spectral valleys; speech compression; stable all-pole filter; vowels; weighted line spectrum pair polynomials; weighted sum; weighted-sum line spectrum pair; Acoustics; Autocorrelation; Bit rate; Dynamic range; Matched filters; Polynomials; Predictive models; Signal processing algorithms; Speech processing; Symmetric matrices;
Journal_Title :
Signal Processing Letters, IEEE
DOI :
10.1109/LSP.2003.811635