| 摘要 |
PURPOSE:To keep the synchronization state immediately after the recovery of a transmission state by allowing a synchronization control section to be transited to the state of synchronization acquisition only when a correlation value is lower than a correlation threshold value and out of synchronism takes place and only when a period of out of synchronism continues for a predetermined time. CONSTITUTION:A correlation integration value being an output of a correlation integration device 4 and a correlation threshold value set by a correlation threshold value setting section 9 are compared by a comparator 8 and the result is inputted to a synchronization control section 13. The control section 13 implements synchronization tracing control at out of synchronism and when the correlation is lower than the correlation threshold value and out of synchronism takes place and a period for out of synchronism continues for a predetermined time (data bit number), the state transits to the synchronization acquisition. Even when the correlation value is lower than the correlation threshold value due to tentative deteriorated transmission state, by the of the synchronization control section 13, the code clock of a spread code is kept to a reference frequency. Thus, after the recovery of the transmission state, when the deviation in a transmission signal is fluctuated within the synchronization tracing range of a DLL (synchronization lock means), the synchronization trace is immediately operated to keep the synchronization state. |
