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.

翻译：本文提出VaN3Twin——首个开源的、全栈式网络数字孪生框架，用于通过光线追踪实现精确物理层建模，模拟多种车联网通信技术的共存场景。VaN3Twin通过集成Sionna光线追踪器扩展了ms-van3t仿真器，能够高保真地呈现无线传播特性，包括多样化的视距传播条件（重点关注其他车辆网格造成的视距阻塞）、多普勒效应以及场景相关效应（如散射与衍射）。与传统仿真工具不同，该框架支持在共享频谱上对DSRC与C-V2X技术进行真实的共存性分析。专用干扰追踪模块可在时频资源块级别捕获跨技术干扰，并通过消除独立视距/非视距传播模型引发的双峰效应等伪影，提升信干噪比估计精度。与实地测量数据相比，在当前最先进的仿真工具基础上，VaN3Twin将应用层误差降低了50%（乡村环境）与70%以上（城市环境），证明了其在可扩展且精准的基于数字孪生的V2X共存仿真中的价值。