The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 24, 2009
Filed:
Sep. 24, 2003
Eung Don Lee, Daejeon, KR;
DO Young Kim, Daejeon, KR;
Bong Tae Kim, Daejeon, KR;
Electronics and Telecommunications Research Institute, Daejeon, KR;
Abstract
Provided are a combined, fixed codebook searching method and apparatus used in a code excited linear prediction (CELP) speech codec. The method is used in a code excited linear prediction (CELP) speech codec, and includes searching for a fixed codebook using a full search method that searches for the fixed codebook at all pulse positions; selecting a fixed codebook searching method by counting the number of users who are accessing a gateway, comparing the number of users with a predetermined threshold, and selecting a proper fixed codebook searching method based on the result of comparison; searching for the fixed codebook using the selected fixed codebook searching method; and checking whether the search for the fixed codebook is complete for all tracks of the CELP speech codec, terminating a routine of searching for the fixed codebook when it is determined the search is complete for all the tracks, and selecting a fixed codebook searching method again in consideration of the number of gateway users when there remains a track to be searched for. Accordingly, a fixed codebook searching method is selected in consideration of the number of users who are accessing a gateway, thereby enabling an effective adjustment of either the quality of sound or the channel capacity of the gateway.