Digital back-propagation (DBP) is a technique for compensating all

fiber Fiber or fibre (from la, fibra, links=no) is a natural or artificial substance that is significantly longer than it is wide. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorpora ...

impairments in optical transmission systems. DBP is a sort of non-linearity compensation (NLC). DBP uses the back-propagation

algorithm In mathematics and computer science, an algorithm () is a finite sequence of rigorous instructions, typically used to solve a class of specific problems or to perform a computation. Algorithms are used as specifications for performing ...

in the digital domain by solving the inverse nonlinear

Schrödinger equation The Schrödinger equation is a linear partial differential equation that governs the wave function of a quantum-mechanical system. It is a key result in quantum mechanics, and its discovery was a significant landmark in the development of th ...

of the fiber link using the split-step Fourier method (SSFM) to calculate the transmitted signal from the received signal. In principle, digital back-propagation is capable of fully reversing the effects of nonlinear propagation in optical fibers, yet in practice it is limited by the stochastic nature of some impairments, like

amplified spontaneous emission Amplified spontaneous emission (ASE) or superluminescence is light, produced by spontaneous emission, that has been optically amplified by the process of stimulated emission in a gain medium. It is inherent in the field of random lasers. Origins ...

and

polarization mode dispersion Polarization mode dispersion (PMD) is a form of modal dispersion where two different polarizations of light in a waveguide, which normally travel at the same speed, travel at different speeds due to random imperfections and asymmetries, causing ...

References

{{reflist Fiber-optic communications