Patent application number | Description | Published |
20110286741 | APPARATUS AND METHOD FOR MONITORING STATISTICAL CHARACTERISTICS OF PHASE NOISES, AND COHERENT OPTICAL COMMUNICATION RECEIVER - This invention relates to an apparatus and a method for monitoring statistical characteristics of phase noises, as well as to a coherent optical communication receiver. The apparatus for monitoring statistical characteristics of phase noises comprises an argument calculating unit ( | 11-24-2011 |
20120026860 | APPARATUS AND METHOD FOR CROSS PHASE MODULATION RECOVERY - Apparatus and method for cross phase modulation recovery are disclosed. An apparatus for cross phase modulation recovery may include M stages of cross phase modulation recovering devices connected in cascade, wherein M≧2, and each stage of the M-stages of cross phase modulation recovering devices is configured to perform cross phase modulation recovery to a polarization de-multiplexed signal input into the each stage. An optical coherent receiver including such an apparatus for cross phase modulation recovery is also disclosed. | 02-02-2012 |
20120290244 | METHOD AND APPARATUS FOR COMPENSATING NONLINEAR DAMAGE - A method and apparatus for compensating nonlinear damage are disclosed. The method for compensating nonlinear damage, including: determining an additive parameter indicating an amount of nonlinear damage based on a plurality of sampled signal sets among which a sampling time of an input signal varies according to different time; and subtracting the additive parameter from the input signal. | 11-15-2012 |
20130108260 | METHOD AND APPARATUS FOR ADAPTIVE NONLINEAR EQUALIZATION IN A POLARIZATION MULTIPLEXING OPTICAL COMMUNICATION SYSTEM | 05-02-2013 |
20130230313 | METHOD AND APPARATUS FOR COMPENSATING NONLINEAR DAMAGE - The embodiments relate to a method and an apparatus for compensating nonlinear damage. The method and apparatus being used in a dual-polarization communication system, the method comprising: calculating, according to input time-domain signals, a plurality of multiplicative parameters indicative of nonlinear damages to the input signals; constructing a plurality of multiplicators by using the plurality of multiplicative parameters; and compensating the input time-domain signals by using the plurality of multiplicators. | 09-05-2013 |
20130243433 | INVERSE CHANNEL APPARATUS AND TRANSMITTER, RECEIVER AND SYSTEM CONTAINING THE APPARATUS - The embodiments of the present invention 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 of the present invention 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. | 09-19-2013 |
20130266311 | METHOD AND APPARATUS FOR ESTIMATING CROSS-PHASE MODULATION IMPAIRMENTS - A system for estimating cross-phase modulation (XPM) impairments, wherein the method comprises: determining, according to a pump Jones matrix of a pump channel and a probe Jones matrix of a probe channel of each of fiber spans except for the first fiber span in a fiber transmission system, a polarization mode dispersion (PMD)-induced relative polarization status rotation matrix between channels of the each of fiber spans; and determining, according to the rotation matrix of the each of fiber spans, dispersion of a pump signal of the each of fiber spans, differential delay of the pump signal relative to a probe signal of the each of fiber spans and a gain of the each of fiber spans, polarization crosstalk and phase noise of the XPM impairments in the fiber transmission system. This allows the XPM impairments in the effect of the polarization mode dispersion to be quickly and accurately estimated, | 10-10-2013 |
20130272719 | Method and Apparatus for Compensating Nonlinear Distortions in Intensity Modulation-Direct Detection System - The embodiments of the present invention provide a method and an apparatus for compensating nonlinear distortions in an intensity modulation-direct detection (IM-DD) system; wherein the method comprises: calculating, according to nonlinear coefficients and differences between values of an input signal at different time, nonlinear distortions of the input signal, so as to eliminate the nonlinearity distortions. By applying the method and the apparatus provided by the embodiments of the present invention, nonlinear cost of the IM-DD system can be effectively reduced, thereby improving the system capacity. | 10-17-2013 |
20140095129 | NONLINEAR TERM SELECTION APPARATUS AND METHOD, IDENTIFICATION SYSTEM AND COMPENSATION SYSTEM - The embodiments of the present invention provide a nonlinear term selection apparatus and method, an identification system and a compensation system. The selection apparatus comprises: a linear coefficient calculator configured to measure linear properties of a nonlinear system by using measurement data, so as to obtain a plurality of linear coefficients; and a nonlinear term selector configured to select nonlinear model expanded terms of the nonlinear system by using the plurality of linear coefficients, so as to obtain nonlinear terms of the nonlinear system. With the embodiments of the present invention, the nonlinear model may be simplified, and the complexity of the nonlinear model may be lowered. | 04-03-2014 |