Duobinary receiver

An optical receiver, comprising:

• a signal converter adapted to convert an optical signal into an electrical signal having an amplitude corresponding to optical power of the optical signal;
• and
• a decoder coupled to the signal converter and adapted to (i) sample the electrical signal using a sampling window and (ii) generate a bit sequence corresponding to the optical signal, wherein:
• the sampling window has a width;
• the electrical signal has a series of waveforms comprising first and second pluralities of waveforms, wherein each waveform of the first plurality represents a binary “0” and each waveform of the second plurality represents a binary “1” ;
• the decoder is adapted to:
• integrate each waveform over the sampling window width to generate an integration result;
• compare the integration result with a decision threshold value to generate a corresponding bit value;
• and
• select the sampling window width to be less than a bit length in the electrical signal in order to reduce contribution of the second plurality of waveforms into integration results corresponding to the first plurality of waveforms;
• the optical signal is an optical duobinary signal;
• and
• the sampling window width is less than about 25% of a bit length.

An optical communication system, comprising an optical transmitter and an optical receiver coupled via a transmission link, wherein the optical receiver comprises:

• a signal converter adapted to convert an optical signal received from the transmitter via the transmission link into an electrical signal having an amplitude corresponding to optical power of the optical signal;
• and
• a decoder coupled to the signal converter and adapted to (i) sample the electrical signal using a sampling window and (ii) generate a bit sequence corresponding to the optical signal, wherein:
• the sampling window has a width;
• the electrical signal has a series of waveforms comprising first and second pluralities of waveforms, wherein each waveform of the first plurality represents a binary “0” and each waveform of the second plurality represents a binary “1”;
• the decoder is adapted to:
• integrate each waveform over the sampling window width to generate an integration result;
• compare the integration result with a decision threshold value to generate a corresponding bit value;
• and
• select the sampling window width to be less than a bit length in the electrical signal in order to reduce contribution of the second plurality of waveforms into integration results corresponding to the first plurality of waveforms;
• the optical signal is an optical duobinary signal;
• and
• the sampling window width is less than about 25% of a bit length.

An optical receiver, comprising:

• means for converting an optical signal into an electrical signal having an amplitude corresponding to optical power of the optical signal;
• and
• means for sampling the electrical signal using a sampling window to generate a bit sequence corresponding to the optical signal, wherein:
• the sampling window has a width:
• the electrical signal has a series of waveforms comprising first and second pluralities of waveforms, wherein each waveform of the first plurality represents a binary “0” and each waveform of the second plurality represents a binary “1”;
• each waveform is integrated over the sampling window width to generate an integration result;
• the integration result is compared with a decision threshold value to generate a corresponding bit value;
• and
• the sampling window width is selected to be less than a bit length in the electrical signal in order to reduce contribution of the second plurality of waveforms into integration results corresponding to the first plurality of waveforms;
• the optical signal is an optical duobinary signal;
• and
• the sampling window width is less than about 25% of a bit length.