公开(公告)号：DE2860220D1

公开(公告)日：1981-01-22

申请号：DE2860220

申请日：1978-12-08

Applicant: IBM

Inventor： ESTEBAN DANIEL JACQUES ,  GALAND CLAUDE ROBERT ,  MAUDUIT DANIEL ,  MENEZ JEAN

IPC: H03M7/30 ,  H04B1/66 ,  H04B14/04 ,  G10L1/08

Abstract: A voice signal is transmitted digitally at reduced bit rate by use of data compression. The original frequency components of a telephone band width of the voice signal sampled at 8 KHz and quantized with 12 bits are transformed into three parameters: SIGNAL data representing adaptive quantization for lower frequency (300-800 Hz) sub-bands; COEF data representing pre-emphasized parcor type coefficients for the higher frequency (800-3000 Hz) band; and, ENERGY data representing higher frequency short term energy level. The three parameters are multiplexed for transmission in binary-code form, thereby representing a recoding of the original binary-coded voice signals.