High-Fidelity RF Mapping: Assessing Environmental Modeling in 6G Network Digital Twins

TL;DR

This paper introduces two metrics, HRT and CRT, to evaluate the accuracy of environmental models in digital twins for 6G RF mapping, using high-fidelity simulations of urban scenarios with environmental changes.

Contribution

It proposes novel metrics for comparing ray tracing simulations and assesses their effectiveness in high-fidelity environmental modeling for 6G digital twins.

Findings

HRT and CRT effectively identify differences in simulation scenarios.

Metrics highlight areas affected by environmental changes.

Vehicular ray tracing reveals realistic distance patterns.

Abstract

The design of accurate Digital Twins (DTs) of electromagnetic environments strictly depends on the fidelity of the underlying environmental modeling. Evaluating the differences among diverse levels of modeling accuracy is key to determine the relevance of the model features towards both efficient and accurate DT simulations. In this paper, we propose two metrics, the Hausdorff ray tracing (HRT) and chamfer ray tracing (CRT) distances, to consistently compare the temporal, angular and power features between two ray tracing simulations performed on 3D scenarios featured by environmental changes. To evaluate the introduced metrics, we considered a high-fidelity digital twin model of an area of Milan, Italy and we enriched it with two different types of environmental changes: (i) the inclusion of parked vehicles meshes, and (ii) the segmentation of the buildings facade faces to separate the windows mesh components from the rest of the building. We performed grid-based and vehicular ray tracing simulations at 28 GHz carrier frequency on the obtained scenarios integrating the NVIDIA Sionna RT ray tracing simulator with the SUMO vehicular traffic simulator. Both the HRT and CRT metrics highlighted the areas of the scenarios where the simulated radio propagation features differ owing to the introduced mesh integrations, while the vehicular ray tracing simulations allowed to uncover the distance patterns arising along realistic vehicular trajectories.