Brian P Mccarthy

US Patent:

56300166, May 13, 1997

Filed:

Mar 7, 1996

Appl. No.:

8/614777

Inventors:

Kumar Swaminathan - Gaithersburg MD
Brian M. McCarthy - Lafayette Hill PA

Assignee:

Hughes Electronics - Los Angeles CA

International Classification:

G10L 900

US Classification:

395 237

Abstract:

A digital discontinuous cellular communication system has a transmitter that transmits two frames of data following detection of voice inactivity. A receiver includes a comfort noise generator that uses the two frames of data to output noise to the speaker during period of voice inactivity. The comfort noise generator includes synthesis codebook with samples scaled by actual background noise and excitation codebook with samples filtered and scaled by the background noise that are combined to produce comfort noise having attributes and loudness level of the received background noise prior to interruption of transmission. The scaled signals are weighted to vary the loudness level and spectral attributes.

US Patent:

55375090, Jul 16, 1996

Filed:

May 28, 1992

Appl. No.:

7/890747

Inventors:

Kumar Swaminathan - Gaithersburg MD
Brian M. McCarthy - Lafayette Hill PA

Assignee:

Hughes Electronics - Los Angeles CA

International Classification:

G10L 900

US Classification:

395 237

Abstract:

A digital discontinuous cellular communication system has a transmitter that transmits two frames of data following detection of voice inactivity. A receiver includes a comfort noise generator that uses the two frames of data to output noise to the speaker during period of voice inactivity. The comfort noise generator includes synthesis codebook with samples scaled by actual background noise and excitation codebook with samples filtered and scaled by the background noise that are combined to produce comfort noise having attributes and loudness level of the received background noise prior to interruption of transmission. The scaled signals are weighted to vary the loudness level and spectral attributes.