NXP and Volkswagen Roll Out Wi-Fi-Based V2X Automotive Connectivity Technology

October 29, 2019 by Gary Elinoff

Going firmly against the grain, the new system will rely on Wi-Fi, and not 5G.

NXP has announced that its RoadLINK V2X communication solution will be incorporated into the new Volkswagen Golf, which will be the first mainstream European car model equipped with V2X (vehicle-to-everything) technology. V2X enables one vehicle’s safety system to communicate with that of another, with the goal of preventing accidents.


Visualization of V2X communication via NXP's dedicated short-range communication modem

The SAF5400 DSRC (dedicated short-range communication) modem is part of NXP’s RoadLINK solution. Image from NXP


What Is Wi-Fi-p?

Wi-Fi-p has also been known as Wi-Fi P2P, and as Wi-Fi Peer-to-Peer. The term most often used today for this well-established standard is Wi-Fi Direct. What’s unique about Wi-Fi Direct is that it enables two devices to establish a Wi-Fi connection with no need for an internet connection or a wireless router.

WiFi Direct has long been used to allow information transfer between PCs, smartphones, printers, cameras and gaming devices. The connection can be between two devices, or between many. Detailed information can be found at the Wi-Fi Alliance’s website.


Why Wi-Fi-p? The C-V2X vs. DSRC Debate

NXP's announcement mentions that “Wi-Fi-p is only safe and secure V2X technology capable of immediate volume rollout.” V2X based on Wi-Fi is a well-tested technology. For over 10 years, both vehicle manufacturers and system suppliers have been developing, testing and standardizing it to ensure its efficacy in a realistic range of traffic and road conditions. Because of this relentless effort, Wi-Fi will form the core of the European standard that has been adapted for vehicle-to-vehicle as well as for vehicle-to-infrastructure communication.

This represents a milestone in the competition between V2X technologies, namely C-V2X (cellular) and DSRC (also called ITS-G5 in Europe). This summer, the EU parliament announced its decision to support ITS-G5 (PDF). The US, by comparison, has yet to pass any legislation in favor of one side or the other.

As of March of 2019, it looked as though C-V2X was gaining an edge on DSRC, but perhaps this decision in the EU will alter that. Obviously, NXP was one of the companies that supported the C-ITS regulation, but there have been several other V2X providers that have protested the EU's decision, including C-V2X supporters such as Huawei, Qualcomm, and companies like Audi and Ford.

As it stands today, NXP is the only source of a tested 5.9 GHz V2X solution now available in volume production. One of its most important features is its low latency, absolutely essential for real-time accident avoidance systems.

The kicker, of course, is that Wi-Fi-p can work independently of any paid cellular service, drastically reducing the cost to the consumer. However, the framework is flexible enough that cellular-based technologies now under development can be utilized in the future.


The SAF5400 DSRC Modem

This announcement is the fruition of plans NXP set over two years ago. 

The SAF5400, introduced in the fall of 2017, was designed to enable V2X communication. In its announcement release for the chip, NXP claimed that it was the world's first in terms of its one-chip platform and, importantly, its scalability.


The NXP SAF5400 DSRC modem

The SAF5400 DSRC modem. Image used courtesy of NXP


The DSRC modem is designed to be compliant with both IEEE 802.11p and IEEE 1609.4 standards for communications, as well as qualified for AEC-Q100 grade 2. 


Getting on the Road Now

NXP’s RoadLINK V2X Evaluation Kit is based on the company’s SAF5400 single-chip modem. It provides a complete solution for the development of secure V2X onboard units (OBUs). It is designed to make V2X development faster and easier for customers at the forefront of this vital, exciting new arena.


Expectations for the V2X New System

Both NXP and Volkswagen have invested in this technology's potential. This is at least partly because it may check several boxes needed for scalable, widely-adopted V2X. 

The system makes provisions for both V2V (vehicle-to-vehicle) communication and V2I (vehicle-to-infrastructure) communication. The former, V2V, is important because it allows cars to exploit the sensor data of other connected cars, a functionality that makes it possible for vehicles to "see" hazards a mile ahead of itself, even around corners and bends in the road. The latter, V2I, makes it possible for vehicles to speak to smart infrastructure such as traffic lights and street signs in smart cities. 

The system should also be able to tap into other ADAS sensing technologies such as cameras and LiDAR, increasing its ability to sense pedestrians and cyclists, among other environmental objects.

While smart cities and ADAS in vehicles are still developing in most parts of the world, NXP has laid its groundwork for the next generation of V2X.