Wavelength demultiplexing of Nyquist WDM signals under large frequency offsets in digital coherent receivers

We propose a novel wavelength-demultiplexing algorithm applicable to Nyquist WDM systems. The proposed scheme features the ability of perfect wavelength demultiplexing even under the frequency offset half as large as the symbol rate. Through simulations and experiments, effectiveness of our scheme is demonstrated in 16-QAM Nyquist WDM systems.