The Model And Simulation Of Short-Range Optical Communication System With Vcsel

The technology of optical communication have developed rapidly and made much progress since Dr Gao Kun won the Nobel’s Prize in physics. The backbone network of most parts of countries has been built well which is at the top of the prosperity. However, there is still room for the development of Access Network, which connected to our life. It is a big problem to solve the improving the signal in the "last one kilometer ". The numerical model of short-range communication system was built, which includes VCSEL and multi-mode fiber, the details as following:Firstly, learning the circuit model of VCSEL and building the numerical VCSEL model based on the rate-equation, which simulates the power roll-off, threshold, small-signal modulation response. Next, we built the multimode VCSEL model, which can model the competition between different modes. The diffraction of output signal can be modeled in Gaussian beam theory.Secondly, as the first medium in short range communication, the Multimode Fiber may generate different mode with different excitation. The relevant mode and mode power distribution can be computed when the specific offset is given. The model neglects the PMD and loss, but considers the modal dispersion for reason of the short range. Finally, the optimal parameter can be extracted by the numerical method. The model can determine the interval of search at the first time. All these technique help the model simulating the optical signal transmission through the MMF. In summary, the model is an exact and advantageous tool for short range optical communication.