Common-mode noise filtering with space-divided differential 2x2 VLC for V2V applications

Vehicle-to-Vehicle (V2V) Communication is one of the most promising application opportunities of Visible Light Communication (VLC). This paper suggests a novel transmission technique for VLC-V2V applications, called 2x2 Differential Transmission (2x2 DT). This transmission method exhibits excellent common-mode optical noise rejection performance. This beneficiary property is presented first with simulation results and later with real-life urban traffic measurement as well. After the promising simulation results, a demonstrational automotive-grade VLC-V2V link is presented and investigated for evaluation purposes. The link does not contain electrical filters, optical filters nor optical lenses, hence link costs are kept low and versatility is preserved. With our proposed 2x2 differential solution, both the transmission quality and common-mode optical noise rejection performance is outstanding. Due to the increased sensitivity of the differential VLC transmission regarding crosstalk between channels, a method is suggested for crosstalk reduction for high-quality differential transmission.