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——首个开源全栈网络数字孪生（NDT）框架，通过射线追踪实现精准物理层建模，用于模拟多种车联网（V2X）通信技术的共存场景。VaN3Twin以ms-van3t仿真器为基座，集成Sionna射线追踪器（RT）构成闭环，实现对无线传播过程的高保真表征，涵盖多类视距（LoS）条件，重点突破车辆网格遮挡造成的LoS阻塞、多普勒效应及散射、衍射等场域相关效应。不同于传统仿真工具，该框架支持对DSRC和C-V2X技术在共享频谱上运行的真实共存分析。专用干扰追踪模块可在时频资源块层面捕获跨技术干扰，并通过消除分离式LoS/NLoS传播模型引发的双峰伪像等缺陷，提升信号与干扰加噪声比（SINR）估计精度。与现场实测对比，VaN3Twin在乡村环境中将应用层误差较现有最优仿真工具降低50%，在城市环境中降低超70%，充分彰显其在可扩展、高精度数字孪生驱动的V2X共存仿真中的价值。