## 5 Conclusions  
Further improvements to the resilience of vehicular VLC systems to optical noise and their ability to cope with various conditions represent one of the most important challenges in the development of automotive VLC systems. In this context, this article proposed a novel vehicular VLC receiver architecture that integrates an adaptive FoV mechanism. Thus, the central point of this article involved the development of an automated FoV adaptation subsystem with a mechanical iris positioned in front of a photodetector. This mechanism's adjustments rely upon the irradiance values captured by a multi-angle light sensor, comprising an array of IR photodiodes with an elevation range of \(0^{\circ}\) to \(30^{\circ}\) and an azimuth range of \(-30^{\circ}\) to \(30^{\circ}\). Based on the sunlight intensity and the sun's position relative to the VLC receiver, the mechanical iris can adapt the FoV from \(\pm 1^{\circ}\) to \(\pm 22^{\circ}\).  
In order to demonstrate the benefits of this concept, an intensive experimental evaluation was performed. In the experimental phase, two identical VLC receivers were employed--one featuring an automatic FoV adjustment and the other with a fixed FoV of \(\pm 22^{\circ}\). The test results revealed the benefits of a context-adaptive FoV: situated at a distance of 50 meters from an LED traffic light, under solar irradiance reaching up to 67,000 \(\upmu\)W/cm\({}^{2}\), the receiver equipped with the adjustable mechanism maintained an active link throughout the entire duration of the experiment, exhibiting a BER lower than \(10^{-7}\). On the other hand, the receiver with a fixed FoV consistently experienced saturation and, therefore, frequent losses of connectivity. Based on these results, the conclusion drawn is that such a mechanism can improve the quality of communication in strong sunlight noise, keeping the data link active. Nevertheless, during the experimental testing, it was seen that the IR photodiode network was perfectible, providing rough estimates of the sun's position. Even under these conditions, the system was able to satisfactorily adjust the FoV in order to maintain an active link. Additional software algorithms are needed in order to improve the detection accuracy.  
In the end, one can conclude that this work provided valuable evidence concerning the benefits of an active FoV adaptation in vehicular VLC applications. As such a concept maximizes both noise resilience and mobility, it is expected that it will be further developed and eventually integrated into real-life vehicular VLC systems. As far as we know, this is the first experimental demonstration of such a concept applied in vehicular applications, opening a new path in this research domain.  
Conceptualization, A.-M.C.; data curation, A.-M.C. and C.B.; formal analysis, A.-M.C., S.-A.A. and C.B.; funding acquisition, A.-M.C.; investigation, A.-M.C., S.-A.A. and C.B.; methodology, A.-M.C., S.-A.A. and C.B.; project administration, A.-M.C.; resources, A.-M.C.; software, S.-A.A.; supervision, A.-M.C.; validation, A.-M.C. and C.B.; visualization, S.-A.A.; writing--original draft, A.-M.C. and C.B.; writing--review and editing, A.-M.C., S.-A.A. and C.B. All authors have read and agreed to the published version of the manuscript.  
This work was supported by a grant from the Ministry of Research, Innovation and Digitization, CNCS--UEFISCDI, project number PN-III-P1-1.1-TE-2021-1371, within PNCDI III.  
Not applicable.  
Data availability StatementData are contained within the article.  
The authors declare no conflicts of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.