Variable Length Words-Pulse Code Modulation

After a very brief resume of conventional pulse code modulation (PCM) features, this paper describes the operating principles of a variable length words - pulse code modulation system (VLWPCM). This new concept is a combination of TASI and conventional PCM. Time assignment speech interpolation or TASI is used on the very long routes, such as transoceanic cables, to improve the yield of the circuits at the cost of a very sophisticated terminal. The combination with PCM allows us to simplify the terminals in such a way that it can yield a lower cost. A coder and a decoder are described.