| 摘要 |
PURPOSE:To detect stably a frame synchronizing pattern by selecting the combination of phases where the correlation of the frame synchronizing pattern and the reception signal series is the highest when a plural-phase combination detector detects the frame synchronization pattern. CONSTITUTION:Four correlation devices 3, 5, 6, 8 collate the contents of the stored pattern and of shift registers 4, 7, and output number of coincident bits as the degree of correlation. The output is processed by adders 91-94, the result is converted into a correlation value based on (P, Q), (the inverse of P, Q), and (Q, the inverse of P) and (Q, P) phase. When any of the correlation values of (P, Q), (the inverse of P, Q), (Q, the inverse of P) and (Q, P) is a predetermined value (threshold value), a discrimination device 10 outputs '1' to an output terminal 12. Even when the correlation of two phases exceeds the threshold value, the maximum value is only one and the phase discriminator 11 discriminates the phase giving the maximum value. |
