| 摘要 |
PURPOSE:To always obtain a correct synchronizing state even in the case of a signal input on the way of maximum value detection in which correct synchronizing state is not obtained by providing a control circuit detecting a maximum value again after the discrimination of synchronization in a synchronous circuit for a receiver employing the spread spectrum modulation system. CONSTITUTION:A synchronization control circuit 7 receiving a synchronization discrimination signal 107 from a synchronization discrimination circuit 3 and activating a maximum value detection circuit 4 is provided in addition to a conventional circuit. A period M1 in the output 102 of a correlations detector 2 is a period when a maximum value is detected and an input signal comes from a phase psi1 on the way. The phase at the maximum correlation is psimax1 and the synchronization is discriminated at the phase psimax1 for a succeeding section D. As a result of synchronization discrimination, when the synchronization discrimination circuit 3 discriminates the state to be synchronization state, a synchronization discrimination signal 107 is outputted and the synchronization control circuit for the succeeding detection of maximum value outputs a command signal 108 to activate the maximum value detection circuit 4 only once, A period M2 is a period for implementing the maximum value detection and since the input signal is inputted from the start, the correct synchronization state is obtained. |
