Outage and Rate Analysis for Industrial Internet of Things in Multi-Tier Visible Light Communication Networks Inside Finite 3D Space

In this paper, downlink multi-tier visible light communication (VLC) networks in the Industrial Internet of Things (IIoT) are studied in terms of outage probability and achievable rate. The industrial VLC network is modeled as a multi-tier network in a finite space under limited receiver field-of-view (FOV), in which access points (APs) of each tier at their own height follow a Poisson point process (PPP) distribution. Random interference between different tiers in the multi-tier network and the boundary effects in a finite space lead to difficulties in analysis, so we propose a new stochastic geometric based analytical framework to tackle this problem. Our analytical expressions precisely capture the impact of typical IIoT device’s FOV and position in a finite space on the outage probability and average achievable rate. For a typical IIoT device which is far away from the boundary, the boundary effect is found to be negligible. Finally, the analytical results are verified by simulations. We observe that the changes in the FOV and the number of APs mainly affect interference and cell coverage, and further influence the network performance of multi-tier VLC networks. We also investigate how the other network parameters influence performance metrics, emphasizing that reasonable parameter settings can yield better VLC network performance.