G.726 Adaptive Differential Pulse Code Modulation (ADPCM)

The G.726 uses an ADPCM transcoding technique to convert a 64Kbits/s A-Law or Mu-Law Pulse Code Modulation (PCM) channel to and from 40, 32, 24, 16Kbits/s PCM stream.

The 24 and 16Kbits/s channels are used primarily as overload channels carrying voice in Digital Circuitry Multiplication Equipment (DCME). The 40Kbits/s channels often carry data modem signals in DCME, especially for modems operating at greater than 4800 bits/s.