Speech coding using sparse vector codebook and cyclic shift techniques

USRE35057E · kind E · reissue

Assignee

• BRITISH TELECOMMUNICATIONS public limited company · GB

Inventors

• Daniel K. Freeman · Reading, US
• Ivan Boyd · Ipswich, GB

Key dates

• Filing date: Feb 3, 1993
• Grant date: Oct 10, 1995
• Expiry date: Feb 3, 2013

Classification

• Technology area (CPC —): General

Abstract

Speech is analyzed to derive the parameters of a synthesis filter and the parameters of a suitable excitation which is selected from a codebook of excitation frames. The selection of the codebook entry is facilitated by determining a single-pulse excitation (e.g., using conventional multipulse excitation techniques), and using the position of this pulse to narrow the codebook search.