| 摘要 |
<p>PROBLEM TO BE SOLVED: To attain a second frame synchronization in a short time by locking-on ratio waves after the second search tracking of a receiver at the time of lock- off, and implementing the second frame synchronization if parity coincides when the actual data for one work are acquired. SOLUTION: A CPU implements second frame synchronization at the time of lock-off. Counters virtually repeat the same process as that before lock-off. When the lock-off period exceeds the period set on a time-out counter 16, values of the counters are cleared, and a frames synchronization process is made in the normal process mode because errors against actual data are generated when the period after lock-off becomes long. When it is judged that no time-over occurs, a parity check is made after one word is acquired. If parity coincides, the second frame synchronization is implemented. Frame synchronization is completed with two words at maximum in 1.2sec.</p> |
