# Vehicular Visible Light Communication for Intersection Management +
Footnote †: This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license ([[https://creativecommons.org/licenses/py/4.0/](https://creativecommons.org/licenses/py/4.0/)]([https://creativecommons.org/licenses/py/4.0/](https://creativecommons.org/licenses/py/4.0/))). [PERSON]  
1 Electronics Telecommunications and Computer Department ISEL/IPL, R. Conselheiro [PERSON], 1949-014 Lisboa, Portugal, [EMAIL_ADDRESS] (M.A.V.) 12 CTS-UNINOVA, Quinta da Torre, Monte da Caparica, 2829-516 Caparica, Portugal 23 Instituto de Telecomunicacoes, Instituto Superior Tecnico, 1049-01 Lisboa, Portugal 3  
[PERSON]  
1 Electronics Telecommunications and Computer Department ISEL/IPL, R. Conselheiro [PERSON], 1949-014 Lisboa, Portugal, mvieira  
Intersection Manager (IM) can increase the throughput of the intersection by directing incoming Connected Autonomous Vehicles (CAVs) [6; 7; 8; 9]. Intersections, by their nature, easily become traffic bottlenecks and conflict areas. Whenever there are two-way-two-way, four-legged, or split intersections on the road network, they are vital either from an operational perspective or from a safety perspective, because they cause considerable delays in traffic. Traffic volumes that arrive at the intersection, i.e., its demand, is the same. For the selection process to be effective, several other factors must be considered, such as road safety, performance, vehicle delay, and operational and functional requirements. The level of service at intersections can be improved by applying a split intersection. Here, the conventional four-legged intersection can be replaced by two separate intersections. Advantages of a split intersection are: improved safety, since it separates potential conflict points; increased efficiency, since it allows the intersection to handle a greater volume of traffic with less delay; a better synchronization, once corridor travel times are improved on both the major and side streets; and, finally, shorter wait times because fewer traffic signal phases means less time stopping at the intersections. In Vehicular Communication Systems, the vehicles and roadside units are the communicating nodes, providing each other with information, such as safety warnings and traffic information [10]. The visible light communication (VLC) holds special importance when compared to existing forms of wireless communications [11; 12]. VLC is an emerging technology that enables data communication by modulating information on the intensity of the light emitted by LEDs. VLC has a great potential for applications due to their relatively simple design for basic functioning, efficiency, and large geographical distribution. A V-VLC system is predominantly Line of Sight (LOS) due to physical properties of light waves and its propagation characteristics. Additionally, modern vehicles have front- and rear-light modules with optical components that focus light beams. Communications can benefit from this directionality because it reduces collisions and allows spatial reuse of modulation bandwidth. VLC is a precursor of optical communication for large scale-integration with other conventional communication technologies, and a strong candidate for next generation of indoor interconnection and networking, in parallel with radio communications. In this paper, a virtual traffic scenario is proposed and bidirectional communication between the infrastructure and the vehicles is tested, using the VLC request/response concept. The proposed system involves wireless communication, smart sensoring and optical source networks, building up a transdisciplinary approach framed in cyber-physical systems. This paper is organized as follows. After the introduction, and the related work presented in Section 2, in Section 3, the V-VLC system is described and the scenario, architecture, communication protocol, coding/decoding techniques analyzed.