Dispersion Estimation and Compensation Using FrFT and LMS Adaptive Methods for Reliable Optical Communication

In this paper, we propose a fractional Fourier transformation (FrFT) to blindly assess the third-order dispersion in optical fiber communication system. By measuring the chromatic dispersion (CD) at different wavelengths, this technique can estimate the dispersion slope and further it can calculate the third-order dispersion. The Least mean square adaptive method is also utilized at last for the compensation of dispersion effectively. The simulation results exhibit that the estimation error is less than 2% in 28GBaud dual polarization quadrature phase-shift keying (DPQPSK) and 28GBaud dual polarization 16 quadrature amplitude modulation (DP-16QAM) system. Through simulations, the proposed third-order dispersion estimation method is appeared to be powerful against nonlinear and amplified spontaneous emission (ASE) noise. Moreover, to decrease the computational complexity, searching step with coarse and fine granularity is looked to search optimal order of FrFT.