| 摘要 |
PURPOSE:To avoid the reproduction of word synchronism in a erroneous way, by masking the bit pattern the same as the word synchronism pattern in a message. CONSTITUTION:A signal NRZ consists of bit synchronism section B, a word synchronism section W and a message section M. The NR2 is inputted to a word synchronism section 1, which outputs a signal SF1 when a bit pattern the same as the word synchronism pattern exists. A mask pulse generating section 3 generates a negative pulse, P in width (M<P<M+B). This negative pulse is ANDed with the WSF1 to form a signal WSF3. The WSF3 is a mask signal to the same bit pattern as the word synchronizing pattern in the message and the bit synchronism section. |
