| 摘要 |
<p>PURPOSE:To shorten time necessary for acquisition of synchronism at the time of switching channels. CONSTITUTION:In a counter control circuit 103, unmatch bit number CQ1 counted at an unmatch bit counter 102 is compared with first and second threshold values Thp1 and Thp2 for front protection operation. As the result, when the unmatch bit number CQ1 is the first threshold value Thp1 for front protection operation, the normal synchronization recovery is performed by one counting operation of a state counter 104, whereas two or three counting operations of the state counter 104 are performed when the unmatch bit number CQ1 is the second threshold value Thp2 for front protection operation.</p> |
