| 摘要 |
<p>There is provided a decoding device capable of rapidly calculating likelihood information while suppressing increase of the processing amount and the circuit size. The device has a backward probability calculation section (112) for performing backward probability calculation by using two processing systems: one for calculating a backward probability betak from a backward probability betak+2 and the other for calculating a backward probability betak-1 from a backward probability betak+1. More specifically, when k = 1, the two processing systems calculate the backward probabilities beta1 and beta0 in parallel. The backward probabilities calculated are stored in a storage section (114) in the window unit. Moreover, like the backward probabilities, a forward probability calculation section (113) uses two processing systems for calculating forward probabilities alphak and alphak+1 in parallel. After the forward probabilities are calculated, a likelihood calculation section (115) calculates the likelihood information by using the forward probabilities and the backward probabilities stored in the storage section (114).</p> |
