Inverse channel apparatus and transmitter, receiver and system containing the apparatus

Patent metadata

Field	Value
Publication number	US-8995835-B2
Application number	US-201313785366-A
Country	US
Kind code	B2
Filing date	Mar 5, 2013
Priority date	Mar 16, 2012
Publication date	Mar 31, 2015
Grant date	Mar 31, 2015

Abstract

The embodiments provide an inverse channel apparatus and transmitter, receiver and system containing the apparatus; wherein the inverse channel apparatus comprises: an inverse nonlinear calculating unit configured to perform nonlinear additive calculation and nonlinear multiplicative calculation on input signals, so as to obtain signals containing nonlinear damage of the input signals on at least one polarization state; and an inverse linear calculating unit configured to calculate signals containing nonlinear damage and linear damage of the input signals on at least one polarization state according to the signals containing nonlinear damage of the input signals on at least one polarization state and a linear function of a channel. The advantages of the embodiments exist in that a transmitted signal is recovered by being passed through an inverse channel after or before being transmitted in a practical channel, thereby effectively compensating for intra-channel nonlinear damage of an optical fiber communication system.

First claim

The invention claimed is:

1. An inverse channel apparatus, comprising an inverse nonlinear calculating unit and an inverse linear calculating unit, wherein,
the inverse nonlinear calculating unit is configured to perform nonlinear additive calculation and nonlinear multiplicative calculation on input signals, so as to obtain signals containing nonlinear damage of the input signals on at least one polarization state;
the inverse nonlinear calculating unit comprising:
an inverse nonlinear coefficient calculating module configured to calculate nonlinear coefficients of the inverse channel according to channel configuration parameters;
an inverse nonlinear perturbation calculating module configured to calculate nonlinear perturbation within the inverse channel according to the nonlinear coefficients of the inverse channel and the input signals; and
an inverse nonlinear adding and multiplying module configured to calculate signals containing nonlinear damage of the input signals on at least one polarization state according to the nonlinear perturbation within the inverse channel and the input signals;

and the inverse linear calculating unit is configured to calculate signals containing nonlinear damage and linear damage of the input signals on at least one polarization state according to the signals containing nonlinear damage of the input signals on at least one polarization state and a linear function of a channel.

2. The apparatus according to claim 1 , wherein the channel configuration parameters comprise optical fiber parameters, the optical fiber parameters comprising an attenuation factor α and/or a dispersion factor β and/or a nonlinear factor γ;
and wherein the inverse nonlinear coefficient calculating module calculates the nonlinear coefficients of the inverse channel according to inverted values of the optical fiber parameters.

3. The apparatus according to claim 1 , wherein the inverse nonlinear perturbation calculating module is configured to calculate nonlinear perturbation within the inverse channel caused by intra-channel four-wave mixing (IFWM), intra-channel cross phase modulation (IXPM) and self-phase modulation (SPM);
and wherein,
the nonlinear perturbation caused by IFWM is:

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Assignees

• Fujitsu Ltd

Inventors

• Yan Weizhen
• Tao Zhenning

Classifications

• H04B10/2543

  due to fibre non-linearities, e.g. Kerr effect · CPC title

• H04B10/2507 Primary

  for the reduction or elimination of distortion or dispersion · CPC title