Small-Scale Testbed for Evaluating C-V2X Applications on 5G Cellular Networks

TL;DR

This paper presents a small-scale, hardware-in-the-loop testbed for evaluating C-V2X applications on a dedicated 5G network using a 1/10th-scale CAV. The design combines a 5G standalone network, ITS agents (sensor, edge server, and SVEA), NTP-based clock synchronization, and TCP-based NATS messaging to enable end-to-end latency assessment under nominal, overload, and mobility conditions. The authors evaluate a simple shared situational awareness scenario, demonstrating the testbed’s ability to measure latency and stress-test network configurations such as absolute priority scheduling. They show that the testbed supports rapid development and evaluation of 5G C-V2X applications and discuss future work to extend to full SA deployments and handover optimization, with public release of the messaging software. This work provides a practical, scalable platform for researchers and engineers to prototype and validate 5G-based V2X concepts in a controlled, reproducible environment.

Abstract

In this work, we present a small-scale testbed for evaluating the real-life performance of cellular V2X (C-V2X) applications on 5G cellular networks. Despite the growing interest and rapid technology development for V2X applications, researchers still struggle to prototype V2X applications with real wireless networks, hardware, and software in the loop in a controlled environment. To help alleviate this challenge, we present a testbed designed to accelerate development and evaluation of C-V2X applications on 5G cellular networks. By including a small-scale vehicle platform into the testbed design, we significantly reduce the time and effort required to test new C-V2X applications on 5G cellular networks. With a focus around the integration of small-scale vehicle platforms, we detail the design decisions behind the full software and hardware setup of commonly needed intelligent transport system agents (e.g. sensors, servers, vehicles). Moreover, to showcase the testbed's capability to produce industrially-relevant, real world performance evaluations, we present an evaluation of a simple test case inspired from shared situational awareness. Finally, we discuss the upcoming use of the testbed for evaluating 5G cellular network-based shared situational awareness and other C-V2X applications.

Figures (6)

• Figure 1: A snapshot of the 1/10th-scale SVEA platform driving in the presented 5G-based C-V2X testbed in the Kista Innovation Park. More details about the SVEA platform at [https://svea.eecs.kth.se]
• Figure 2: Architecture and Spatial Distribution of our 5G C-V2X Testbed System. There are three types of ITS agents: infrastructure sensor, edge server and CAVs (SVEA). To communicate, the sensor and CAVs have a wireless connection using a 5G cellular network with 20 MHz bandwidth. Each radio cell has ca. 40 Mbps capacity. T1, T2, T3, T4 are the transmission time stamps of the messages used in our evaluation. All agents rely on an NTP server for clock synchronization. The NTP server is reached using the same wired or wireless connection as is used for their main communication.
• Figure 3: Cumulative Distribution Functions (CDFs) of latency for all the different combinations under nominal conditions.
• Figure 4: Latency of individual packets under background load. This test was conducted with message size and frequency of 1 kB at 10 Hz, in BL network configuration, while there was 1 UEs x 5 Mbps uplink and 1 UEs x 110 Mbps downlink load. In red, we see the synchronization error between sensor-server and server-vehicle, respectively.
• Figure 5: Comparison between different cases under overload conditions. The figure depicts 99%, 95%, and mean latency when overloading the network in uplink traffic.