Optical communications – Receiver – Including postcompensation
Reexamination Certificate
2005-04-26
2005-04-26
Negash, Kinfe-Michael (Department: 2633)
Optical communications
Receiver
Including postcompensation
C398S206000, C398S202000, C714S704000, C714S799000, C375S225000
Reexamination Certificate
active
06885828
ABSTRACT:
An optical receiver configuration and method of controlling an optical signal receiver adjusts a decision threshold to reduce the bit error rate (BER). The receiver includes a comparator having a data input and a digital data output. An error detection & correction circuit provides an error signal representative of the number of corrected “1”s and “0”s in the data output from the comparator. Based on the error signal, a control circuit modifies the comparator decision threshold in a direction to reduce the BER of the receiver. Dynamic modification of the decision threshold may also be accomplished. A total percentage error indicator is preferably used as the basis of changing the decision threshold value. The total percentage error indicator may be used to variably adjust the decision threshold by an amount that varies according to the magnitude of the total percentage error indicator to thereby more quickly arrive at an acceptable decision threshold and prevent overshoot. A searching method may also be used to determine the usable range of the comparator before tuning the decision threshold.
REFERENCES:
patent: 5325397 (1994-06-01), Scholz et al.
patent: 6115157 (2000-09-01), Barnard et al.
patent: 6178213 (2001-01-01), McCormack et al.
patent: 6307899 (2001-10-01), Starr et al.
patent: 6487352 (2002-11-01), Sobiski et al.
patent: 1 085 713 (2001-03-01), None
patent: WO 0313030 (2003-02-01), None
Ohta et al., “Automatic Threshold-Level Control (ATC) for Optimum Decision Operation in Optical Repeaters,”Electronics Letters, Nov. 21, 1985, pp. 1148-1149, vol. 21, No. 24.
Form PCT/ISA/220 PCT Search Report, Dec. 18, 2003.
Cammarata Michael R.
Ciena Corporation
Negash Kinfe-Michael
LandOfFree
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