Patent Number: 6,167,371

Title: Speech filter for digital electronic communications

Abstract: A filter device filters a speech signal that has a frequency spectrum featuring slopes separated by valleys. The filter device amplifies the slopes and attenuates the valleys for improving the intelligibility of the signal. The filter device includes a predictive speech signal analysis circuit for determining a polynomial whose coefficients are Linear Predictive Coding (LPC) parameters. The filter device further includes a calculator for synthesizing a digital post filter of the zeroes/poles type based on this polynomial. An extraction circuit of the filter device taps values of poles by extracting roots of the polynomial, and an interpolation circuit between the values of poles derives therefrom the zero values of the post filter.

Inventors: Miet; Gilles (Le Mans, FR), Parayre-Mitzova; Daniela (Le Mans, FR)

Assignee: U.S. Philips Corporation

International Classification: G10L 19/14 (20060101); G10L 19/00 (20060101); G10L 019/14 (); H04B 003/21 (); H04M 001/253 (); H04M 009/08 ()

Expiration Date: 12/26/2017