Harmonic and Intermodulation Distortion Modeling in IM-DD Multi-Band Radio over Fiber Links exploiting Injection Locked Lasers

In the context of Radio-over-Fibre communication systems employing Intensity Modulation-Direct Detection links, the spectral performance of the transmitting laser plays a crucial role in defining link performance with respect to intermodulation distortion. The spectral properties of the transmitter can be enhanced by stabilising the laser through the injection-locking technique. In this work, the injection-locked laser's performance has been analysed by modelling through a properly modified set of rate equations employing two different formulations. Evaluation was done by means of two different numerical approaches. The results, describing time and spectral behaviour as a function of the detuning and of the master rate of injection, are in good agreement despite of the different formulations and numerical methods. Remarkable improvements are shown in comparison with the solitary laser's behaviour, like bandwidth enhancement, noise and frequency chirping reduction, along with an advantageous performance/cost compromise