Comparison of OFDM and OOK modulations for vehicle-to-vehicle visible light communication in real-world driving scenarios

Abstract

Visible light communication (VLC) is seen as an interesting technology to complement the IEEE 802.11p-based systems commonly used for vehicle-to-vehicle (V2V) communication. However, the reliability of such a V2V-VLC link in real-world driving scenario had not been demonstrated up to very recently. The results obtained, at that time with orthogonal frequency division multiplexing (OFDM) at 2 kbps, are complemented in this paper with additional results using on-off keying (OOK) at 100 kbps. The overall performances of this second modulation are rather close to those of OFDM. The packet reception rate (PRR) remains more than 90% over a service area of 30 m length-wise and the link is not affected by multipath propagation. Error-free transmission is even demonstrated over 60 m using repetition coding, at the cost of a reduced data rate of 10 kbps. However, it is shown that OFDM is able to cope with the narrow-band interferences generated by outdoor lighting such as LED signs whereas the OOK link is completely jammed. Despite its simplicity and good overall performances, OOK is thus not as robust as OFDM to the variety of situations experienced in real-world driving scenario.