| 摘要 |
Frame synchronization is quickly established to acquire an RF channel in a short time. Numerically controlled oscillators 1 - 1 to 1 - 3 , complex calculation circuits 2 - 1 to 2 - 3 , band limit filters 3 - 1 to 3 - 3 , a selector 7 , a phase error detection circuit 9 , a loop filter 10 , and an AFC circuit 11 compose a carrier regeneration loop for removing the frequency error of the carrier included in an in-phase component I and a quadrant component Q of the baseband signal input to the complex calculation circuits 2 - 1 to 2 - 3 . A timing generator 6 detects which of frame synchronization pattern detection circuits 5 - 1 to 5 - 3 has detected a frame synchronization pattern, provides the selector 7 with a selection signal corresponding to the decision result, and sends a switch signal to the AFC circuit 11 . Thereafter, the carrier for removing the frequency error included in the baseband signal is regenerated to acquire an RF channel in a short time.
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