A decoupled power and data simultaneous transmission method in laser wireless power transfer system

Abstract

The laser power transfer (LPT) system is one of the most promising systems in the long-rang wireless power transfer field. An interesting extension of LPT technology is the combination with optical communication. However, traditional optical communication technology for LPT system suffers from crosstalk issue, which leads to instability of power transmission and inaccuracy of data decoding in practical application. In this paper, a data modulation method is proposed to guide the modulation process of laser input current. Thus, the data can be directly incorporated into the optical power delivery path without inducing power fluctuation at receiver. Furthermore, based on the proposed data modulation method, a laser power supply consisting of a constant-current converter and a bidirectional converter is employed. It is possible that the desired modulated laser input current may be affected by the laser input voltage due to the bandwidth limitation of the laser power supply. Thus, a feed-forward scheme is also introduced to ensure the laser power supply can output desired modulated current. Finally, the experimental results are shown to validate the theoretical analysis.