Method and apparatus for burst mode clock and data recovery

摘要

Provided is an optical line terminator (OLT) to recover packet data and a clock from an optical signal including a silent interval. The OLT may receive packet data and a clock from at least one optical network unit (ONU). Even in a silent interval in which the at least one ONU does not transmit packet data, the OLT may successfully recover the clock.

主权项

1. An optical line terminator (OLT), comprising:
a receiver configured to receive an optical signal including packet data from one of a plurality of optical network units (ONUs), the received optical signal including a silent interval during which no packet data is transmitted by the ONUs; a power recovery device configured to convert the received optical signal to thereby generate an electrical signal, the generated electrical signal having a temporal position corresponding to that of the received optical signal, such that the generated electrical signal has a silent interval corresponding to that of the received optical signal; and a data inserter connected to the power recovery device and configured to generate an electrical signal including the electrical signal generated by the power recovery device with dummy data in the silent interval, the dummy data having a same transmission rate as, and being synchronized with, the packet data of the received optical signal, to thereby form in the silent interval a monotonous electrical signal from which a clock corresponding to the packet data is recoverable; and a Media Access Control (MAC) device configured to determine start and end points of the silent interval and to generate a control signal indicative thereof, the control signal being sent to the power recovery device and the data inserter, and being configured to cause the power recovery device to stop generating electric signals during the silent interval, and to cause the data inserter to generate the monotonous electrical signal during the silent interval.