| 摘要 |
<p>A branch value output circuit checks a preceding state to which a maximum path metric state determined in a Viterbi decoding process by a Viterbi decoder has transited, uses the maximum path metric state, and determines a branch value between transitions. A correlator determines a correlation in each interval between the branch value and soft-decided received data and outputs a correlative value representing the correlation in each interval. A synchronism/asynchronism determining circuit determines whether the received data are in a synchronous or asynchronous condition based on the correlative value in each interval. If the received data are determined to be in an asynchronous condition by the synchronism/asynchronism determining circuit, the synchronism/asynchronism determining circuit supplies a phase control signal to a phase converter. The phase converter changes the phase of the received data in response to the phase control signal. Therefore, it can be detected whether the soft-decided received data are in the synchronous or asynchronous condition, and if the received data are in the asynchronous condition, the received data are controlled into the synchronous condition. <IMAGE></p> |
