Frequency-Domain Chromatic Dispersion Equalization Using Overlap-Add   Methods in Coherent Optical System
  The frequency domain equalizers (FDEs) employing two types of overlap-add zero-padding (OLA-ZP) methods are applied to compensate the chromatic dispersion in a 112-Gbit/s non-return-to-zero polarization division multiplexed quadrature phase shift keying (NRZ-PDM-QPSK) coherent optical transmission system. Simulation results demonstrate that the OLA-ZP methods can achieve the same acceptable performance as the overlap-save method. The required minimum overlap (or zero-padding) in the FDE is derived, and the optimum fast Fourier transform length to minimize the computational complexity is also analyzed. 
Tianhua Xu, Gunnar Jacobsen, Sergei Popov, Marco Forzati, Jonas   Martensson, Marco Mussolin, Jie Li, Ke Wang, Yimo Zhang, A...
physics.ins-det physics.optics