VaN3Twin: the Multi-Technology V2X Digital Twin with Ray-Tracing in the Loop

TL;DR

VaN3Twin delivers an open-source, full-stack Network Digital Twin for multi-RAT V2X simulations by integrating the Sionna Ray Tracer with the ms-van3t framework. It enables high-fidelity PHY modeling, including LoS/NLoS, Doppler, and site-specific effects, while providing a unified coexistence module to analyze cross-technology interference on a time-frequency grid. Validation against rural and urban field measurements shows substantial gains in RSSI alignment and packet reception accuracy compared to 3GPP-based stochastic models, and reveals significant differences in SINR and decoding outcomes under realistic interference scenarios. The framework supports scalable, city-scale coexisting V2X experiments and offers a foundation for standardization, site-specific validation, and advanced vehicular applications that rely on accurate PHY-level modeling.

Abstract

This paper presents VaN3Twin-the first open-source, full-stack Network Digital Twin (NDT) framework for simulating the coexistence of multiple Vehicle-to-Everything (V2X) communication technologies with accurate physical-layer modeling via ray tracing. VaN3Twin extends the ms-van3t simulator by integrating Sionna Ray Tracer (RT) in the loop, enabling high-fidelity representation of wireless propagation, including diverse Line-of-Sight (LoS) conditions with focus on LoS blockage due to other vehicles' meshes, Doppler effect, and site-dependent effects-e.g., scattering and diffraction. Unlike conventional simulation tools, the proposed framework supports realistic coexistence analysis across DSRC and C-V2X technologies operating over shared spectrum. A dedicated interference tracking module captures cross-technology interference at the time-frequency resource block level and enhances signal-to-interference-plus-noise ratio (SINR) estimation by eliminating artifacts such as the bimodal behavior induced by separate LoS/NLoS propagation models. Compared to field measurements, VaN3Twin reduces application-layer disagreement by 50% in rural and over 70% in urban environments with respect to current state-of-the-art simulation tools, demonstrating its value for scalable and accurate digital twin-based V2X coexistence simulation.

Figures (10)

• Figure 1: An overview of the proposed VaN3Twin framework: ms-van3t high-level architecture with Sionna RT integration.
• Figure 2: Flowchart of the entire VaN3Twin framework for the coexistence simulation.
• Figure 3: Areas of the two measurement campaigns in Sali Vercellese, Vercelli, Italy (a) and its DT (b) and Turin, Italy (c) and its DT (d), rural and urban scenarios, respectively. In both DTs the static $T_x$ antenna is represented as the red marker, while the $R_x$ is yellow and moves along the green trajectory.
• Figure 4: Vehicle setup for field tests.
• Figure 5: Measured and simulated RSSI values (a) and their Probability Density Function (b) for the rural measurement campaign in Sali Vercellese, Vercelli, Italy.