| 摘要 |
<p>The present invention relates to a device provided in particular for performing the processing of the Viterbi algorithm. The Viterbi algorithm is defined by its constraint length of value n + 1 and its 2<n> states associated with bit strings, the processing having the object of estimating an initial string of bits b(i), from a transmitted string resulting from a transmission operation performed on the initial string. The device comprises a processor and an operator provided to establish the maximum metric of order r of the state Ej, called Metr(Ej), for r greater than n, and the (r-n)nth bit of the string corresponding to this metric, from input values which are the maximum metrics of order r-1 of the states E2k and E2k+1, denoted Metr-1(E2k) and Metr-1(E2k+1), and the conditional probabilities in respect of the said states E2k, E2k+1 of the rth bit of the strings associated with these states having a specified value, called Pr(b(r) = O/E2k) and Pr(b(r) = O/E2k+1) for example, k being equal to 2j for all j less than 2<n-1> and equalling 2(j-2<n-1>) for all j greater than or equal to 2<n-1>, so that Metr(Ej) takes the value of the larger of the two following expressions, the first being Metr-1(E2k) + Pr(b(r) = O/E2k) and the second being Metr-1(E2k+1) + Pr(b(r) = O/E2k+1). <IMAGE></p> |
