Digital demodulator architecture

摘要

Methods, systems, and devices are described for a digital demodulator device for processing received optical signals. The device may include a quadrature error filter that receives a digitized version of an optical signal, and removes quadrature errors to generate a filtered series of data samples. The device may also include a frequency offset removal module for performing frequency rotation on the filtered series of data samples. The device may include a chromatic dispersion compensation module which removes chromatic dispersion from horizontal and vertical polarization channels. The device may include a polarization mode dispersion (PMD)/polarization dependent loss (PDL) compensation module which compensates for interference caused by PMD and PDL. The device may also include a phase recovery module configured to track and correct phase.

主权项

1. A digital demodulator device for received optical signals, the digital demodulator comprising:
a quadrature error filter module configured to:
receive a digitized version of an optical signal; andremove quadrature errors to generate a corrected series of data samples; a frequency offset removal module configured to perform frequency rotation on the corrected series of data samples to generate a frequency corrected series of data samples; a chromatic dispersion compensation module configured to remove, from the frequency corrected series of data samples, chromatic dispersion from horizontal and vertical polarization channels; a matched filter decimator configured to implement an interpolation function that provides decimation on samples taken at substantially two+ε times the symbol rate; a polarization mode dispersion (PMD)/polarization dependent loss (PDL) compensation module configured to compensate the frequency corrected series of data samples for interference caused by PMD and PDL; and a phase recovery module configured to track and correct phase for the frequency corrected series of data samples.