The vehicular network which serves the base automotive use case consists of On-Board Units (OBUs) in the vehicles and roadside units (RSUs) connected to the Internet through an Ethernet interface. As shown in the Figure 1, the vehicles connect among each other via standard IEEE 802.11p/ WAVE links, and are connected to the RSUs and the Internet through IEEE 802.11p/ WAVE, IEEE 802.11g/ WiFi or cellular links.
Each vehicle is equipped with an OBU with multiple wireless interfaces, which enable the vehicles to communicate both with other vehicles and with RSUs that are integrated in the infrastructure. OBUs and RSUs have a similar hardware, except for the antennas, which have higher gains in the RSUs. An example of an OBU is depicted in Figure 2.
The OBU includes the following elements:
- Single-Board Computer (SBC)
- Dedicated Short Range Communication (DSRC) wireless interface (IEEE 802.11p)
- WiFi interface (IEEE 802.11a/b/g/n)
- 4G Interface
- GPS receiver
- Antennas for each technology (round antenna is for WiFi and rectangular antenna is for IEEE 802.11p).
The OBUs are running a tailored Linux distribution based on Buildroot. The kernel was customized to include new features such as clock synchronization, as required by IEEE 802.11p. The driver was further extended to meet the requirements of IEEE 802.11p/WAVE. The RSUs have the same hardware as the OBUs, except for the cellular interface (which they do not require) and the Ethernet interface (required to connect to a switch from the fiber infrastructure).
Each vehicle will have access to its own information such as velocity, GPS, camera and heading. This information will be used by the embedded in-Car Node Processor within the car to take local decisions, and it can also be advertised to the other vehicles (Figure 3). Each vehicle will also have access to information from the street and surroundings through embedded video cameras (with VNF transcoding) on the other vehicles and sensors (crossing roads and traffic lights, vehicles in the road, bad conditions in the road, etc.). This information can be sent and disseminated through vehicles (through DSRC technology), or to a Wi-Fi station in the street, and then be disseminated to the vehicles in the area. With all this information, each vehicle can access its own information and the one gathered through other vehicles. Vehicles may use this information to support a variety of use cases, e.g., assisted driving, autonomous driving, collision avoidance, accident detection, emergency messages dissemination, On-Board Diagnosis (OBD) for car self-repairing, etc.
V2X communications may work directly between vehicles (802.11p/WAVE) or using a infrastructure (4G/5G) through VNF Unified Gateway (B-COM partner). For the ITav automotive testbed both V2V and V2I are possible, enabling different experimentation forms.
- 10 x RSUs/OBUs Single-Board Computer (SBC), Dedicated Short Range Communication (DSRC) wireless interface (IEEE 802.11p), WiFi interface (IEEE 802.11a/b/g/n), 4G Interface, GPS receiver, Antennas for each technology (round antenna is for WiFi and rectangular antenna is for IEEE 802.11p, and higher gains antennas in the RSUs).
- 5 x ESP8266 devices to emulate the traffic signals through Wi-fi client and server based approach, and 1 x GoPro Hero 4 for video streaming.
- 5 x In-Car Node Processor: 3 ARM RaspberryPi V3 model B, and 2 x node processor x86 with 8 GB RAM and 8 core i7 processors.
- 1 x small cell C-RAN using Band 7 (2.6GHz) for testing purposes (testing license is required “ANACOM/PT”), 2 x Sim Cards 4G/LTE UICC Open Card for subscribers provisioning and 2 x 4G dongles, 1 x OAI EPC running on Xeon-based virtual machine (6 vCPU; RAM 10Gb; Disk 250GB).
Experimenters will have access to real OBUs, RSUs, ESP8266 devices and video cameras, having also the possibility to create and deploy their own VNFs from the 5GinFire portal within the ITav automotive testbed. Experimenters will have access to a controlled environment in the lab, with the possibility to evaluate and validate their own automotive VNFs services in terms of V2X communication performance and metrics (e.g., latency vs overhead, throughput vs packet loss, etc.) and test their own automotive VNFs within the car with its diversity of contextual-aware information gathered from extra sensors (traffic signals) and from OBUs internal sensors available (accelerometers, heading, speed, link quality connection, GPS, compass, RSSI, car neighbor’s density, etc.).
These experiments can be also performed in a controlled environment on the outside.
Possible VNFs to be included and tested comprise Li-Fi communication between cars, Car crash detection and emergency info dissemination, OBD (On-Board Diagnosis for self-repairing), Collision Avoidance (machine learning) and others.
Lucas Guardalben (email@example.com) and Susana Sargento (firstname.lastname@example.org)
Instituto de Telecomunicações, Aveiro, Portugal (IT-Av)
Campus Universitário de Santiago, 3810-193 AVEIRO – PORTUGAL