A new technique, related to the Viterbi algorithm for simultaneous phase jitter tracking and data detection of signals transmitted over the dispersive channel with Gaussian noise is proposed. This technique produces a reliable phase estimate and avoids the poor receiver performance which occurs with Viterbi decoding in the presence of phase jitter due to the use of a phase estimate derived from unreliable preliminary decisions. The effectiveness of this approach is demonstrated through computer simulation of the voiceband channel. It was found that for the case of a typical meeting the combined requirements of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">C2</tex> and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">D1</tex> conditioning and signaled at 14,400 bits/s, no errors were experienced in a computer simulation run of 2000 symbols compared to a previous run with a less sophisticated phase tracking algorithm which experienced 17 errors in 2000 symbols.