Nonlinear equalization method and system for adaptive optical fiber communication based on direct detection

Abstract

The invention discloses a self-adaptive optical fiber communication nonlinear balancing method and system based on direct detection. The method comprises following steps that: known predetermined data are sent through a sender; the sent data are received at a receiver; modeling is carried out to the nonlinear balancing digital signal processing model at the receiver by using a Volterra nonlinear model according to the sent known predetermined data and the received data; the Volterra nonlinear model is equipped with N-level Volterra series; the N is a positive integer; the Volterra kernel of each level of the Volterra nonlinear model is estimated; a corresponding threshold value is set for the Volterra kernel of each level; the Volterra kernels exceeding the corresponding threshold values are eliminated from the Volterra kernel of each level so as to obtain the updated Volterra kernels; estimation is carried out to the updated Volterra kernels again so as to obtain the final Volterra kernels; and the Volterra nonlinear model is generated by using the final Volterra kernels, thus carrying out digital compensation and recovery.

Description

technical field [0001] The invention relates to the field of optical fiber communication, in particular to an adaptive nonlinear digital signal processing method and system based on intensity modulation and direct detection. Background technique [0002] The current low-cost optical fiber communication system usually adopts the method of intensity modulation and direct detection, and is mainly used in the fields of optical interconnection, access network and metropolitan area network. Affected by the nonlinear effects (signal beat noise and fiber nonlinear noise) of optical fiber communication systems, the transmission distance of current systems based on intensity modulation and direct detection is limited. Although the nonlinear compensation algorithm has been applied to some optical fiber communication systems, its complexity is too high to be suitable for practical optical fiber communication systems. Contents of the invention [0003] According to one aspect of the p...

AI Technical Summary

Problems solved by technology

Affected by the nonlinear effects of optical fiber communication systems (signal beat frequency noise and fiber nonlinear noise), the transmission distance of current systems based on intensity modulation and direct detection are limited

Although the nonlinear compensation algorithm has been applied to some optical fiber communication systems, its complexity is too high to be suitable for actual optical fiber communication systems

Images