Laser Diode Modelling for Wireless Power Transmission

Wireless power transmission using laser beaming can be realized with arrays of high power semiconductor laser diodes. In this paper we present a complete model for a single power emitter diode characterized by a tapered amplifying section and a quantum well active layer. The band mixing technique has been used for gain calculation and the Transmission Line Laser Modelling (TLLM) for evaluating the electromagnetic propagation inside a tapered waveguide. Moreover we present a complete time domain analysis, which allows to include non linear effects. The model has been completed with a proper set of rate equation for carrier distribution and sources to take into account the Amplified Spontaneous Emission (ASE) noise. A real device has been simulated and the results are reported and discussed. In particular we have demonstrated that mode conversion becomes overestimated when less than 600 sections are used in the proposed model, or when the step size is greater than 1.5 μm.