7 results about "Residual dispersion" patented technology

The invention discloses a power distribution estimation method for optical performance monitoring of an optical communication system, and relates to the technical field of optical communication. A received signal is preprocessed to generate a complex value signal, the complex value signal is divided into two paths of signals, one path of signals is subjected to standard digital signal processing, the other path of signals is subjected to partial dispersion compensation, nonlinear compensation and residual dispersion compensation after dispersion reloading, absolute values of the two paths of signals are taken for related processing, and power is obtained; a power distribution diagram is obtained after repeated processing for n times, links of the power distribution diagram are changed, insertion losses are added to different link sections, then power is obtained by repeating the calculation method, multiple power distribution diagrams are obtained after repeated processing for n times, and all obtained power distribution diagram data are input into a deep neural network to train and recognize abnormal power distribution; according to the power distribution estimation method for optical performance monitoring of the optical communication system, the nonlinear Kerr effect of the optical fiber is utilized for longitudinal monitoring, and power distribution of multiple cross optical links is measured.

The application discloses a Fourier domain mode locked laser based on a laser dynamic establishment process and a control method, and comprises a ring laser cavity which is composed of an optical amplifier, a first isolator, a second isolator, an adjustable filter, a delay optical fiber, a coupler and a polarization controller or an optical amplifier, a first isolator, a second isolator, an adjustable filter, a delay optical fiber, a coupler, an intensity modulator and a polarization controller. When the dispersion amount in the ring laser cavity exceeds the bandwidth range of the adjustable filter, the optical amplifier or the intensity modulator is controlled to restart, so that the laser signal is restarted instead of the signal in the continuous gain cavity, the residual dispersion in the cavity is resisted, high coherent swept laser output is realized, any dispersion compensation technology is not needed, the scheme is simple, the requirements of the devices used for the laser are low, environment control technology is not needed, the scheme has strong robustness, the cost is reduced, and the Fourier domain mode locked laser can be applied to any waveband.

The application belongs to the technical field of optical fiber communication, and discloses an optical fiber transmission link quality monitoring and dispersion compensation optimization method and system, which comprises the following steps: extracting an error vector amplitude, an optical signal-to-noise ratio and constellation distortion features from a coherent receiver and fusing them into a comprehensive quality evaluation index; jointly estimating residual dispersion by using a clock recovery phase and equalizer coefficient distribution; adopting a variable step gradient descent to adaptively optimize dispersion compensation filter parameters; performing performance degradation trend analysis and early warning; and jointly monitoring and cooperatively optimizing multiple wavelength channels.

An optical receiver includes a dispersion compensation circuit that compensates for chromatic dispersion of an optical transmission line, for an electric signal corresponding to an optical signal received through the optical transmission line, an adaptive equalization circuit that adaptively compensates for residual chromatic dispersion remaining due to insufficient compensation in the dispersion compensation circuit, for a compensated electric signal by the dispersion compensation circuit, and a monitor circuit that monitors a dispersion slope of the residual chromatic dispersion based on a tap coefficient of the adaptive equalizer circuit. The dispersion compensation circuit compensates for the chromatic dispersion based on a monitor value of the dispersion slope.

The invention belongs to the technical field of optical fiber communication, and discloses an optical fiber transmission link quality monitoring and dispersion compensation optimization method and system, and the method comprises the steps: extracting an error vector amplitude, an optical signal-to-noise ratio and a constellation diagram distortion feature from a coherent receiver, and fusing the features into a comprehensive quality evaluation index; according to the method, residual dispersion is jointly estimated by using clock recovery phase and equalizer coefficient distribution, parameters of a dispersion compensation filter are adaptively optimized by adopting variable step gradient descent, and performance degradation trend analysis and early warning and multi-wavelength channel joint monitoring and collaborative optimization are carried out.

The invention relates to the technical field of optical signal processing, in particular to a real-time carrier recovery method and system. According to the invention, the FFT scheme is used to estimate the frequency offset, and the anti-interference capability of the system to the residual dispersion is improved. And aiming at the problem of high hardware overhead of the traditional complex number quadruple operation, quadruple amplification of the phase is equivalently realized by adopting absolute value operation, and about 70% of LUT resource overhead is saved. And the compensation phase angle output by the frequency offset estimation module is directly compensated in the polar coordinate system, so that compensation in a Cartesian coordinate system is avoided, and about 80% of LUT resource overhead is saved.

An optical power distribution estimation device includes: a partial wavelength dispersion application unit that applies, to a signal, partial wavelength dispersion corresponding to a distance from an optical transmission device to an optical power measurement position; a nonlinear operation unit that performs, on the signal to which the partial wavelength dispersion has been applied, nonlinear operation using a linear term obtained by Taylor-expanding a mathematical expression used for phase rotation; a residual dispersion application unit that applies residual wavelength dispersion corresponding to a distance from the optical power measurement position to an optical reception device to the signal subjected to the nonlinear operation by the nonlinear operation unit; and a correlation calculation unit that estimates an optical power distribution of an optical transmission line by obtaining, for each optical power measurement position, a correlation between the signal to which the residual wavelength dispersion has been applied and a reception signal based on an optical signal transmitted from the optical transmission device and received via the optical transmission line.