Multicarrier digital fractional fourier transform for coherent optical communications

A new coherent optical transmission system is proposed that makes use of the digital multicarrier fractional Fourier transform to obtain serial optical Nyquist pulses at the receiver side in the time domain by adopting the time-lens effect. Theoretical time-lens effect is derived based on fractional Fourier transform (FrFT) and chromatic dispersion effect. A fundamental study to explore the limits of the proposed system is performed and detailed results have been presented. System performance evaluation confirms reduced complexity at the receiver side.