## 5 Conclusions  
In this paper, we present an analysis of a SISO UM-VLC system with dust particles suspended in the UM environment and atmospheric parameters. Furthermore, and as the main contribution of this manuscript, we propose a hemispherical 3D dust particle distribution model that more accurately represents the UM hostile environment. The mathematical modeling and the derivation of the statistical parameters of this scatter distribution model allows to present a more coherent scattering channel component produced by the dust particles and to establish a precise and compact general mathematical model of the UM-VLC channel. The performance of the dust particle distribution analytical framework and the improvement of the UM-VLC channel model are evaluated and verified in a UM-VLC system based on computational numerical simulations based on the IEEE 802.1.5.7 standard by varying the number of distributed dust particles in terms of CIR, received power, SNR, RMS delay spread, and BER. The findings based on the CIR are relevant to verify that the temporal dispersion for any number of dust particles is higher compared to similar works in the literature. However, when comparing the curves with values of \(N=150\) and \(N=200\), we observe that they are very similar (approximately between \(4\times 10^{-6}\) and \(5\times 10^{-6}\) at their maximum values). These results demonstrate that as the amount of suspended dust particles increases, the CIR decreases in magnitude. The results of the received power, SNR, and RMS delay spread are presented as empirical CDFs and distributions in the UM scenario by varying the number of dust particles. These findings reaffirm that the 3D hemispherical dust particle distribution model derived in this article describes more accurately the UM scenario with respect to basic dust particle distributions found in the literature. This is due to the fact that the real interaction of the light with the scatterers, in general, worsens the performance of the UM-VLC system since the power received and the SNR decrease, and greater time delays are generated. Finally, the system has a better performance in terms of BER when fewer dust particles are considered. On the other hand, the worst performance of the curves occurs for values of \(N=150\) and \(N=200\). These findings reinforce the criteria that the system performance depends directly on the number of dust particles found in the distribution implemented in the UM-VLC scenario. By presenting a more accurate UM-VLC channel model through the enhancement of the channel component produced by scattering, as future work, it is necessary to present solutions that mitigate the problems generated in the UM-VLC system when there is a greater amount of dust particles. Among these solutions are reception mechanisms based on machine learning and angular diversity receivers. Furthermore, we will validate experimentally the UM-VLC channel model including the scattering components and the distribution of dust particles proposed in this article. This experimental test-bed will have all the features of a UM tunnel to verify the behavior of the VLC system in this  
Figure 8: BER curves for different values of \(N\) in the hemispheric area of the evaluated UM-VLC scenario and the UM-VLC reference scenario, Reprinted from ref. [12]. environment. Furthermore, and as future work, a deeper statistical development (second-order statistics and probability distributions) of the hemispherical distribution of dust particles, the behavior of dust particles when interacting with light, and the UM-VLC scattering channel model component should be evaluated and analyzed. Conceptualization, P.P.J. and C.A.A.-M.; methodology, P.P.J. ; software, P.P.J. ; validation, C.A.A.-M., I.S. ([PERSON]), A.D.F., D.Z.-B., F.S. and I.S. ([PERSON]); formal analysis, P.P.J. ; investigation, P.P.J. ; resources, C.A.A.-M.; data curation, P.P.J. ; writing--original draft preparation, P.P.J. ; writing--review and editing, P.P.J., C.A.A.-M., I.S. ([PERSON]), A.D.F., D.Z.-B. and F.S., and I.S.