High-Speed Visible Light Communications Using ZnSe-Based White Light Emitting Diode

In this letter, we report, for the first time, an experimental study on improving modulation rate of a ZnSe-based white light emitting diode (LED). The white LED exhibits a color temperature of ~6400 K (x = 0.31 and y = 0.37), which is almost independent of the injected current. In order to improve the LED's modulation rate, we use peaking and carrier sweep-out effects generated by our proposed current-shaping circuit. The experimental results confirm that we can significantly improve the ON-OFF keying modulation rate of a 30 MHz-bandwidth ZnSe-based white LED by a factor of 7. An error free transmission link has been demonstrated at a data rate of 400 Mb/s.