• Implementation of Maximum Likelihood Decoders for Convolutional Codes

      Clark, George C., Jr.; Radiation Incorporated (International Foundation for Telemetering, 1971-09)
      Maximum likelihood decoding of convolutional codes is finding considerable application in communication systems and several decoders of this type have recently been built. These decoders implement an evolved form of a decoding procedure that was originally described by Viterbi in 1967. In this document we describe the problems of reducing the Viterbi algorithm to hardware, the various tradeoffs and compromises that must be made, and the short cuts that are available. In addition an interesting variation on the Viterbi algorithm is described which results in favorable implementation particularly at high data rates.