Novel Visible Light Communication Method Using the Pulse Waveform of Serial Communication

Visible light communication (VLC) using the electromagnetic wave in visible light band is a kind of wireless communication technology. In general, the transmission and reception elements of VLC are controlled by a microcomputer in a VLC module which makes high and low voltages at time slots correspond by the binary data. A timer interruption controls the timing of sending and reading the slots in the transmitter and the receiver, respectively. A timer interruption is an operation for performing thread processing by pausing the main function. By the specification of the timer interrupt, it becomes difficult to output the slot accurately as the communication speed increases. And it becomes difficult to accurately read. Here, we focus on the function of serial communication. serial communication can support time slots control as an embedded function. We propose the novel control method for VLC elements using the pulse waveform of serial communication where the sending and reading timings are controlled by the embedded serial function. This method makes VLC easy and can control the time slots more severely. We compare the symbol error rate for each communication speed. And we show that the proposed method is more accurate than the conventional method.