Abstract: Consistent with the present disclosure, circuitry may be provided in an optical receiver that can determine a bit error rate (BER) associated with an incoming signal by dividing the number of errored bits in a frame alignment signals (FAS) by the number of bits in the FAS. Accordingly, although an optical signal may be severely degraded and forward error correction (FEC) cannot be performed, a BER may be obtained if the FAS can be identified. The BER can then be used in a feedback loop to control various optical or electrical components in the receiver to improve or reduce the BER to a level, for example, at which FEC can be performed.

Abstract: Consistent with the present disclosure, circuitry may be provided in an optical receiver that can determine a bit error rate (BER) associated with an incoming signal by dividing the number of errored bits in a frame alignment signals (FAS) by the number of bits in the FAS. Accordingly, although an optical signal may be severely degraded and forward error correction (FEC) cannot be performed, a BER may be obtained if the FAS can be identified. The BER can then be used in a feedback loop to control various optical or electrical components in the receiver to improve or reduce the BER to a level, for example, at which FEC can be performed.

Abstract: An apparatus and method for uniformly sharing across a plurality of channel signals FEC coding gain which may be achieved through FEC encoding of a higher baud rate electrical data signal or through multiplexed or combined electrical data signals from multiple data sources prior to their subsequent demultiplexing and separate generation into optical channel signals which are multiplexed and launched onto an optical transmission medium. The optical signal generation is achieved through reverse multiplexing of the higher baud rate data signal or of the multiplexed, FEC encoded plural data signals.

Abstract: An enhanced forward error correction system is disclosed. Transmitted data is encoded into codewords in multiple dimensions. The decoding of received data by a decoder is performed in multiple passes in each dimension, with corrected data provided as an output from each pass into another decoder for the next decode pass. The encoder in one embodiment comprises a parallel inner RS(247,239) encoder or encoders and parallel outer BCH(255,247) encoder or encoders. Additional steps are added for error multiplication reduction. The system provides an approach to detect generally uncorrectable patterns for concatenated codes and provides a correction mechanism for improving error correction performance.

Abstract: An apparatus and method for uniformly sharing across a plurality of channel signals FEC coding gain which may be achieved through FEC encoding of a higher baud rate electrical data signal or through multiplexed or combined electrical data signals from multiple data sources prior to their subsequent demultiplexing and separate generation into optical channel signals which are multiplexed and launched onto an optical transmission medium. The optical signal generation is achieved through reverse multiplexing of the higher baud rate data signal or of the multiplexed, FEC encoded plural data signals.

Abstract: An enhanced forward error correction system is disclosed. Transmitted data is encoded into codewords in multiple dimensions. The decoding of received data by a decoder is performed in multiple passes in each dimension, with corrected data provided as an output from each pass into another decoder for the next decode pass. The encoder in one embodiment comprises a parallel inner RS(247,239) encoder or encoders and parallel outer BCH(255,247) encoder or encoders. Additional steps are added for error multiplication reduction. The system provides an approach to detect generally uncorrectable patterns for concatenated codes and provides a correction mechanism for improving error correction performance.

Abstract: An error correction system for coding codewords comprises a multi-symbol encoder and a multi-symbol decoder for respectively encoding codewords using a multi-symbol per clock and decoding codewords using a multi-symbol per clock. The multi-symbol encoder and decoder may employ Reed-Solomon codes for encoding and decoding process.