Patent ID: 9729232
Date: 2017-08-08
CPC Classifications: H04B

Claim:
1. A dispersion estimation and compensation method in optical coherent communication, comprising the following steps that are executed by a digital signal processor of a digital coherent receiver: performing an imbalance compensation on an IQ; performing dispersion estimation; and performing dispersion compensation by using a dispersion value provided by the dispersion estimation; wherein performing the dispersion estimation comprises: performing a fast Fourier transform on IQ-imbalance compensated data to obtain frequency domain data in two polarization directions; respectively calculating autocorrelation sequences of the frequency domain data in the two polarization directions to obtain values of the two autocorrelation sequences corresponding to the frequency domain data in the two polarization directions; respectively performing the fast inverse Fourier transform on the values of the two autocorrelation sequences to obtain two inverse Fourier transform results; respectively calculating modulus squares of the two fast inverse Fourier transform results to obtain two modulus square results; adding the two modulus square results to obtain a sum of the modulus square results P[n]; for a plurality of IQ-imbalance compensated data, calculating a plurality of sums of the modulus square results, averaging all sums of the modulus square results to obtain a dispersion objective function P[n]; calculating an index n