Chromatic Dispersion Monitoring Method Based on Phase Shift Technique

The modulation phase shift method was used to measure chromatic dispersion in a standard single mode fiber for telecommunication. The modulation phase difference of the transmitted light at the wavelength of 1532.16 nm modulated by a radio frequency signal was measured, relative to the transmitted light at the wavelength of 1549.33 nm modulated by the same signal. By introducing a reference light at the wavelength of 1310 nm, a 1310/1550 nm wavelength division multiplexing was used instead of the high cost dense wavelength division multiplexing. In the experiment, two testing lights were coupled with the reference light to the fiber spools of different lengths, respectively. By finite difference method, the chromatic dispersion between the two testing lights was measured, and the fixed errors generated during transmission were less than 0.5 ps/(nm·km).

A novel chromatic dispersion monitoring method for 400 Gbit/s 256 QAM fiber-optic system based on asynchronous amplitude sampling

A novel chromatic dispersion(CD) monitoring technique based on asynchronous amplitude sampling(AAS) is proposed for a higher modulation format and higher rate system.The dispersion and other impairment factors can be separated with the definition of monitoring parameter M.A 400 Gbit/s 256 quadrature amplitude modulation(QAM)system is built using Optisystem 13.0 beta software.Simulations of CD monitoring technique for different bandwidths of sampling Gaussian filter,optical signal to noise ratios(OSNRs) and duty cycles are investigated,and the tolerance is also discussed.Simulation results show that the method can be less affected by noise,and a higher accuracy of 600 ps/(nm.km) can be achieved.The technique supports a wide range of data traffic and enhances operation flexibility of optical networks.

A novel chromatic dispersion monitoring method for 1 024 QAM fiber-optic system based on asynchronous amplitude sampling

A new chromatic dispersion(CD) monitoring method is proposed, and the CD monitoring is achieved on the whole range of 0—600 ps/nm. A dual-polarization(DP)-1 024 quadrature amplitude modulation(QAM) 400 Gbit/s CD monitoring system is built using OptiS ystem14.0 software. With different optical signal to noise ratio(OSNR) values, different filter bandwidths or different duty cycles, the simulations are carried out. The simulation results show that this new CD monitoring method can be less affected by noise and has a high tolerance for different filter bandwidths. At the same time, this method can do effective CD monitoring on the signal with duty cycle greater than 80%. A high sensitivity in 0—200 ps/nm can be achieved using this CD monitoring method. The technique supports a wide range of data traffic and enhances operation flexibility of optical networks.