Patent ID: 9391731
Filing Date: 2016-07-12
CPC Classification: H04J

Claim Text:
1. A method of recovering information bits from a received signal in which information bits are recovered using a post digital filter and maximum likelihood sequence estimation (MLSE), decoding, the method comprising: receiving a signal in a Nyquist coherent optical receiver, wherein the signal is a Nyquist WDM signal or a faster-than Nyquist WDM signal; generating a plurality of digital samples from the received signal using a polarization beam splitter, a 90° optical hybrid, a photodiode and an analog to digital converter (ADC); performing digital signal processing (DSP) in the Nyquist coherent optical receiver to generate a plurality of values; applying the post-digital filter to remove a sufficient portion of high frequency components from a signal output of the DSP to reduce a bandwidth requirement of the photodiode and the ADC; and performing a maximum likelihood sequence estimation (MLSE) on the plurality of digital samples.