Controlled adaptive prediction delta modulation in mobile radio voice communications
Chih‐Cheng Huang · 2003
Controlled adaptive prediction delta modulation (CAPDM) is a median-rate ( approximately 15 kb/s) speech coding scheme which combines the features of one-step looking forward decisions, syllabic companding, instantaneous companding, and adaptive prediction. Its parameters can be adjusted such that it achieves high-quality voice transmission under good channel conditions and achieves communication-quality voice transmission under bursty-type channel errors in mobile radio environments. From the results of large-scale computer simulation and subjective listening tests, it was found that CAPDM performs much better than continuously variable slope delta (CVSD) modulation in a mobile radio fading channel.>