| 摘要 |
Decoding signals represented by a trellis of a block length divided into windows includes a step of decoding a portion of the trellis using backward recursion starting from a point that is after the end of a window backwards to the end of the window, defining a learning period, to determine a known state metric at the end of the window. A length of the learning period for each window dependents on the signal quality such that a shorter learning period is chosen for a higher signal quality. The signal quality used is an intrinsic signal-to-noise ratio derived from the log-likelihood-ratio of the soft outputs of the decoded window. In particular, the intrinsic signal-to-noise ratio of the signal is defined as a summation of generated extrinsic information multiplied by a log-likelihood-ratio (LLR) value at each iteration. |
