Complex channel path loss model for Industrial Internet of Things scenarios

The Industrial Internet of Things (IIoT) scenario utilizes the interaction and collaboration of many communication and industrial devices, to realize the various industrial automation applications. The channels for such scenarios are featured with multi-frequency bands, strong reflections, dense scatterings and mobile obstructions. Thus, it is a huge challenge to propose an accurate path loss model, which is the key to establishing reliable wireless communication links, under such environments. In this paper, based on the results of ray tracing, firstly, a path loss model for multi-frequency bands is proposed, additionally, the partition attenuation factor with linear frequency dependency is constructed. Then, the distance, frequency, and propagation condition dependent metal machinery path loss correction term, which describes the additional path loss caused by large metal machinery or dense metal scatters, is introduced in the proposed model. Lastly, the impacts of the movement of the industrial robots on the path loss are investigated. The proposed model is simple and precise. It can well describe the influence of the features of IIoT channels on the path loss. The models and the results can provide vital information for the link budget and hotspot deployment for IIoT scenarios.