| 摘要 |
A fast settling amplifier for use in a phase locking system operative to phase lock a local clock to incoming data bits in a packet of short duration within a specified accuracy range, using no more than a few initial bits of the packet. Phase locking is achieved by phase shifting the data packet bits relative to a local clock signal a fixed, non-integral fraction of a bit period until the phasing lies within the specified range. The phasing is then accurate enough to permit signal decoding with an open loop over the limited duration of the packet. The phase locking process is activated each time the beginning of a new packet is detected. A Manchester code is typically utilized as the representation of the signal upon which synchronization is achieved. The Manchester code or biphase signal is recovered from the telecommunications network by a fast settling amplifier that rapidly establishes thresholding to accurately distinguish between high and low level signal levels in the Manchester code while maintaining a well filtered signal level.
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