RP Photonics

Software … powerful tools for your research & development!


RP Fiber Power – Simulation and Design Software
for Fiber Optics, Amplifiers and Fiber Lasers

Example Case: Data Transmission through a Germanosilicate Fiber

Description of the Model

Here, we simulate the transmission of a data signal in a glass fiber. The mode parameters of the fiber are calculated with the mode solver from a given germanium doping profile.

A pseudorandom NRZ (non return to zero) signal with 40 Gbit/s is created and propagated through 5 km of the fiber.


Figure 1 shows the signal before and after the fiber. There are substantial signal distortions, caused mainly by the chromatic dispersion and to some extent also from the Kerr nonlinearity.

telecom signal before and after the fiber

Figure 1: Time-dependent power of the pseudorandom bit sequence before and after the fiber.

Figure 2 shows an eye diagram. As the “eye” is wide open, the signal could still be well detected. For twice the fiber length (not shown here), this would be different.

eye diagram for the telecom signal after the fiber

Figure 2: Eye diagram for the telecom signal after the fiber.

Of course, one could easily include further aspects in the simulation, for example a chirp of the input signal.

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