Combined Source and Channel Coding for Variable-Bit-Rate Speech Transmission

1.1 Motivation Every communication channel has an optimum rate for digital transmission of speech. If the actual rate is below the optimum, speech * Bell Laboratories. + University of Lund, Sweden. °Copyright 1983, American Telephone & Telegraph Company. Photo reproduction for noncommercial use is permitted without payment of royalty provided that each reproduction is done without alteration and that the Journal reference and copyright notice are included on the first page. The title and abstract, but no other portions, of this paper may be copied or distributed royalty free by computer-based and other information-service systems without further permission. Permission to reproduce or republish any other portion of this paper must be obtained from the Editor.