Car-to-Car Communication Using RF Cognitive Radio With VLC Common Control Channel

This paper combines the advantages of both cognitive radio (CR) and visible light communication (VLC) for car-to-car applications to achieve a high data rate with minimum (delay, outage probability, bit error rate (BER), and cost). CR technology hops among the existing radio frequency (RF) available channels to increase the RF spectrum usage efficiency and dodge the scarcity limitation. Moreover, using CR as a license-free application will reduce car-to-car communication running costs. However, CRs require a common control channel (CCC) to communicate the spectrum availability map within the CR network and to inform the receiver end about the change in the transmitter-end channel. Therefore, the CCC is the bottleneck in the car-to-car CR network. Then, we explore the types of CCCs and discuss using each of them to solve this bottleneck issue. In the proposed scheme, we adopt using VLC as CCC. A MATLAB simulation for a car-to-car framework is built to demonstrate the capabilities of VLC through the chosen metrics (i.e., data rate, delay, outage probability, cost, and bit error rate). Our results show that VLC achieves up to 90% of the licensed data rate with a small outage probability of 21.2% and moderate BER and delay. In addition, VLC presents the minimum cost, placing second after the licensed type with a score of 84.2% in the combined metric. In conclusion, with the VLC's bright future of expansion and growth in the car-to-car application, we have proven that VLC is worthy of implementation practically in modern cars.