Patent ID: 6934343

Claim:
A method for computing the full path metric (FPM) in a Viterbi decoder that uses modulo normalization, comprising the steps of: (a) determining the maximum state metric value at each stage; (b) comparing the maximum state metric at a current stage to the maximum state metric at a previous stage to determine if a marker point has been crossed; (c) incrementing a counter if the marker point has been crossed in step (b); and (d) determining the FPM using the formula: FPM =( M+C adj )− I−D where D=(M−E) mod(K) , and where “M” is the maximum state metric value for the last stage at the end of frame, “E” is the state metric value for the ending state of the frame used for traceback, “I” is the state metric value for the initial state of the frame, K=2 t is the size of a modulo ring where “t” is the number of bits used to represent the state metric values, and C adj is the value of the counter when it is adjusted by “t” bits.