Evaluation of transmission quality of visible light communication using bit error rate measurement

In this paper, a bit error rate testing system has been developed and the transmission quality of visible light communication was studied. An optimization of reference voltage of the comparator was performed. A measured bit error rate was less than 10
^-7
without a disturbance light. This result indicates that the developed system is applicable in indoor communication. A bit error rate clearly became worse when the disturbance light was inserted. The results showed that this testing system is possible to evaluate quantitatively the effect of disturbance light. Signal to noise ratio (SNR) at the input of comparator was calculated, and measured bit error rate was plotted versus SNR. However, a difference between measurement and theoretical curve was observed. To reduce this difference, the review of noise source and the improvement of the mounting method for transmitter/receiver, will be required.