## 2 Related Work
### Vehicular Communication and Driving Safety Applications Issue, Related Works and Methods
#### 2.1.3 Debating the Current State of RF-VLC Hybrid Communications in Road Safety Applications  
The current proposal and direction in which the applications of our research group are developing can only compare certain modules with those currently existing in the literature. This is due to the development of several systems in parallel on different communication principles and protocols. Some of them work on the basis of RF communications, some with VLC communications, and this paper incorporates these communications in a hybrid form of RF-VLC in the first stage. The main goal is to highlight the capacity and portability of the developed system but also the amount of information that can be analyses, processed, and transmitted through such a system, whether we are talking about RF or VLC communications. In the first stage, the development of the system is presented in this paper for demonstration purposes in order to highlight the need for a system that encompasses all the deficiencies that exist at this time in production, as well as issues that have not been addressed by other research groups. Improvements are constant and maintain a direction that solves as many problems as society faces. Future steps also include devices to be installed on the surface of cars to transmit and receive information from other vehicles at a considerable distance. Current studies offer feasible perspectives because the VLC communications realized can support the transmission and reception of information at distances of up to 300 m in ideal conditions [38].  
The analyses and research carried out aimed at performing tests in real scenarios and at behavioral investigation of pedestrians and drivers in an external environment and an existing infrastructure; sensory and video analysis made these elements true sources of information and factors in decision-making in order to prevent loss of life. In the first phase, the development of intelligent systems dedicated to the automotive sector is based on modules designed for adaptability in different situations and on universal design in order to have a greater impact on users. Part of the developed components focuses on the prevention and detection area in the vehicle and another part on the external environment, considered as very volatile and full of challenges and insecurity. The novelty and adaptability of the developed system that is in a continuous process of improvement have the possibility to identify and transmit information through several types of communication, whether we are talking about visible light about 4G or Wi-Fi. The use of these future perspectives in the field of communications facilitates extremely high data traffic, high-quality video calls, online televisions, or video applications that the fourth generation (4G) offers. We can say that the frequency band has values between 1800/2600 GHz, which can facilitate the transfer of information at transfer speeds of about 3 GB/s [39; 40]. Although 4G communications were used in the case of scenarios and applications, also being available to the public, the fifth generation runs at speeds between 10 and 50 Gb/s, using an initial frequency of 1800 GHz and 2600 GHz, with subsequent adjustments that can increase between 30 and 300 GHz. Studies conducted by private research centers show that in laboratory tests in ideal conditions the technology reaches speeds of about 1 Tb/s. To consolidate the claims and expose them to the public, in 2019 the Einride company, that deals with certain aspects of the development of applications dedicated to Ericson, have managed the performance of controlling a truck remotely over a distance of about 1200 km on the Gothenburg, Sweden to Barcelona, Spain. The results and the way the tests were performed made the experiment a success and the conclusions were that, in the field of vehicle applications, 5G communications can manage and communicate information in a timely manner with extremely low latencies [41; 42].