Transmitter, receiver, and coding scheme to increase data rate and decrease bit error rate of an optical data link

A method of encoding k bit blocks of data into n bit blocks, each of said n bit blocks comprising one of said k bit blocks of data and (n−k) parity bits, said method comprising

• providing said k bits to a first latch,
• feeding said k bits through Q−1 pipeline stages, with each of said pipeline stages,
• receiving at least k bits;
• computing (n−k) output bits representing said (n−k) parity bits in various stages of computation, in accordance with a defined generator polynomial, with said defined generator polynomial being identical for each of said pipeline stages;
• latching its (n−k) output bits;
• providing its (n−k) output bits.

A pipelined FEC decoder for decoding a k-bit datablock from an n-bit datablock encoded with an (n,k) majority-logic decodable FEC code, said decoder comprising:

• Q stages of latches, each of said latches with n data bits,
• Q−1 combinational logic circuits, each of said combinational logic circuits interconnected between two of said latches, to receive an input of at least k bits representing said k data bits in various stages of decoding from an upstream one of said latches, and provide an output comprising k bits to a downstream one of said latches;
• wherein each of said Q−1 combinational logic circuits comprises a majority logic gate;
• and wherein said Q−1 combinational logic circuits are arranged to decode said k data bits in Q−1 stages.

A optical communications system comprising:

• a transmitter;
• a receiver;
• an optical link communicatively coupling said transmitter to said receiver;
• said transmitter, comprising:
• a forward error correcting (FEC) encoder for encoding data using a pipelineable BCH error correcting code to form forward error correctable data;
• an output stage for outputting said forward error correctable data within a bit stream across said link, said output stage operating at a power and a speed in excess of a first nominal rate, so that errors are introduced in said stream and received at said receiver at a BER that is in excess of a nominal BER;
• said receiver comprising
• a pipelined FEC decoder, operable to correct errors within said forward error correctable data from said receiver using said BCH error correcting code, received on said link so that said data may be received with less than said nominal BER, at a data rate above said first nominal rate, thereby increasing the capacity of said optical link at said power.

An optical transmitter comprising:

• an input for receiving data to be transmitted, comprising:
• a buffer for buffering received data;
• a packet former for encoding data from said buffer into packets;
• a error detection (ED) encoder adding error detection codes to said packets, said error detection codes allowing detection of at least one error in a packet;
• an electrical to optical (E/O) generator in communication with said ED encoder to receive data from said ED encoder and produce at least one optical output signal corresponding thereto for transmission across an optical link and receipt as at least one received optical signal, said optical generator operating at a clock rate in excess of a nominal clock rate, and at a power level that causes errors to be introduced into said at least one received optical signals that are in excess of a first bit error rate (BER);
• and
• a controller in communication with said buffer to cause retransmission of said retransmission blocks within said buffer in response to retransmission requests, so that data may be received at a data rate in excess of said nominal clock rate with less than a second BER.

An optical transmitter comprising:

• an input for receiving data to be transmitted, comprising:
• a buffer for buffering received data;
• a packet former for encoding data from said buffer into packets,
• a plurality of error detection (ED) encoders adding error detection codes to said packets, said error detection codes allowing detection of at least one error in a packet;
• at least one electrical to optical (E/O) generator in communication with said plurality of encoders to receive data from said encoders and produce at least one optical output signal corresponding thereto for transmission across an optical link and receipt as at least one received optical signal, each of said at least one optical generators operating at a nominal clock rate and at a power level that causes errors to be introduced into said received optical signals(s) that are in excess of a first bit error rate (BER);
• and
• a controller in communication with said buffer to cause retransmission of packets within said buffer in response to retransmission requests, so that data may be received with less than a second BER, at a data rate in excess of said nominal clock rate.

An optical receiver comprising:

• an optical to electrical (O/E) regenerator, for receiving an optical stream from a transmitter and generating a corresponding electrical stream;
• an error detection (ED) decoder for decoding data from said electrical stream generating a decoded data stream, and detecting errors in said decoded stream;
• a retransmission request controller in communication with said ED decoder for generating retransmission requests for requesting retransmission of retransmission blocks to be retransmitted by said transmitter within said optical stream,
• wherein said regenerator, said decoder, said retransmission request controller are formed on a single integrated circuit.

An optical transmitter comprising:

• an input for receiving data to be transmitted;
• a buffer for buffering received data;
• a packet former for encoding data from said buffer into retransmission blocks,
• an error detection (ED) encoder adding error detection codes to said retransmission blocks, said ED codes allowing detection of at least one error in a retransmission block;
• a forward error correction (FEC) encoder adding forward error correction codes to said retransmission blocks including said ED codes, said FEC codes allowing detection and correction of at least one error in a retransmission block;
• an electrical to optical (E/O) converter in communication with said FEC encoder to receive said retransmission blocks including said ED codes and said FEC codes from said FEC encoder and produce an optical output corresponding thereto;
• and
• a controller in communication with said buffer to cause retransmission of said retransmission blocks in response to retransmission requests.

An optical transmitter comprising:

• an input for receiving data to be transmitted;
• a buffer for buffering received data;
• a packet former for encoding data from said buffer into retransmission blocks,
• a pipelined error detection (ED) encoder adding error detection codes to said retransmission blocks, said error detection codes allowing detection of at least one error in a retransmission block;
• a forward error correction (FEC) encoder adding forward error correction codes to said retransmission blocks including ED codes, said FEC codes allowing detection and correction of at least one error in a retransmission block;
• an electrical to optical (E/O) generator in communication with said FEC encoder to receive retransmission blocks from said FEC encoder including FEC and ED codes and to produce at least one optical output signal corresponding thereto for transmission across an optical link and receipt as at least one received optical signal, said optical generator operating at a clock rate that causes errors to be introduced into said at least one received optical signal that are in excess of a first bit error rate (BER);
• and
• a controller in communication with said buffer to cause retransmission of said retransmission blocks in response to retransmission requests, so that data may be received with less than a second BER.

An optical receiver comprising:

• an optical to electrical (O/E) regenerator, for receiving an optical stream from a transmitter and generating a corresponding electrical stream;
• a forward error correction (FEC) decoder for decoding data from said electrical stream generating a first decoded data stream,
• an error detection (ED) decoder for decoding data from said first decoded data stream generating a second decoded data stream;
• a retransmission request controller in communication with said ED decoder for generating retransmission requests for requesting retransmission of retransmission blocks to be retransmitted by said transmitter within said optical stream.

An opto-electronic switch formed on an integrated circuit substrate, comprising

• a plurality of optical receivers, each of said optical receivers comprising an optical regenerator in communication with a pipelined FEC decoder for decoding a received data stream;
• a plurality of optical transmitters, each of said transmitters comprising:
• an optical generator and a pipelined forward error correcting code (FEC) encoder, for encoding an output datastream to include FEC codes,
• a electric switch fabric in communication with said plurality of receivers and said plurality of transmitters, to switch FEC decoded data from selected ones of said receivers to selected ones of said transmitters, for transmission as FEC encoded data.