Connected Cars
April 12 2024
We never know when the Sci-Fi friction becomes the reality. In my childhood, I was very much fascinated by Holographic Projectors shown in the “Spiderman” cartoon. Gradually, I have seen a real holographic projector. Same way driverless cars or connected cars which are self-communicating and take decisions on Artificial intelligence (AI) and Machine learning (ML) will be no longer a concept of the future.
The connected car, word seems to be simple but trust me this is a complex system consists of multiple systems and networks that provide the heterogeneous connectivity to Infrastructure, to the cloud computing, AI & ML engines, IoT applications, end user applications and more.
Connecting to the infrastructure (V2V & V2X)
A smart car can communicate to the surroundings like other car (V2V,vehicle to vehicle), infrastructure like mobile towers, Wi-Fi network of a building or IoT infra-structure (V2X, vehicles to infrastructure) and sent its logs for cloud infrastructure (Telematics) where end users are connected. Although we typically think of V2V with lane obstruction or automatic braking system alert, onboard diagnosing, soon the connected cars will be a component of a smart city. How will it look like when the traffic lights automatically reprogram itself based on the traffic pattern and density or the car itself search the available parking space.
The connected infrastructure or V2X will guide the vehicle and provide the environment with the help of which it can sense the real-time parameter and get the alerts which may impact the driving. There are at present following key standards for V2X:
IEEE 802.11p (DSRC)
DSRC operates in the 5.9 gigahertz (GHz) with the bandwidth of 75 Megahertz (MHz) with the operational range of 1km. The original V2X communication happens directly between vehicles and vehicles (V2V) and traffic infrastructure (V2I), which form a vehicular ad-hoc network as two V2X senders come within each other's range. Hence it does not require any communication infrastructure for vehicles to communicate, which is key to assure safety in remote or little-developed areas. WLAN is particularly well-suited for V2X communication, due to its low latency. It transmits messages known as Cooperative Awareness Messages (CAM) or Basic Safety Message (BSM), and Decentralised Environmental Notification Messages (DENM). Other roadside infrastructure related messages are Signal Phase and Timing Message (SPAT), In Vehicle Information Message (IVI), and Service Request Message (SRM). The data volume of these messages is very low. The radio technology is part of the WLAN IEEE 802.11 family of standards and known in the US as Wireless Access in Vehicular Environments (WAVE) and in Europe as ITS-G5.
3GPP (C-V2X)
The direct communication between vehicle and other devices (V2V, V2I) uses so-called PC5 interface. PC5 refers to a reference point where the User Equipment (UE), i.e. mobile handset, directly communicates with another UE over the direct channel. In this case, the communication with the base station is not required. The motivation of the mission-critical communication was to allow law enforcement agencies or emergency rescue to use the LTE communication even when the infrastructure is not available, such as natural disaster scenario. In release 14 onwards, the use of PC5 interface has been expanded to meet various market needs, such as communication involving wearable devices such as smartwatch. In C-V2X, PC5 interface is re-applied to the direct communication in V2V and V2I.
The Cellular V2X mode 4 communication relies on a distributed resource allocation scheme, namely sensing-based semipersistent scheduling which schedules radio resources in a stand-alone fashion in each user equipment (UE). While 3GPP defines the data transport features that enable V2X, it does not include V2X semantic content but proposes usage of ITS-G5 standards like CAM, DENM, BSM, etc over 3GPP V2X data transport features.
Cloud Communication
Telematic devices acquire a Realtime, low latency actionable information from the vehicles and send that information over the air to the desired cloud location (cloud Server). Where that data is processed and converted into meaningful information which helps to take decisions such as,
a. Information about the consumable/damaged part replacement or prior information of parts which are going to create nuisance.
b. Driver behaviour analysis.
c. Optimum utilization of fuel.
Not many OEMs are into V2X functionality testing, compliance and validation but one OEM strongly comes into the picture is Spirent. With this, you can ensure that V2X communications over IEEE802.11p (DSRC) and cellular technology (C-V2X) are compliant to standards and work correctly under all possible conditions - by leveraging test metrics focusing on precision, repeatability and safety. Spirent’s comprehensive test solutions enable the design and deployment of sophisticated V2X test scenarios and communications services while reducing time-consuming field testing. For more information you can visit to the following link:
https://www.spirent.com/products/connected-vehicles-v2x
