Qualcomm has claimed a double first in Colorado in teaming up with Panasonic and Ford to trial Cellular Vehicle-to-Everything (C-V2X) technologies over this summer. The project will assess C-V2X capabilities on roads firstly throughout Panasonic’s own CityNOW headquarters in Denver, followed by deployments in select areas along the state’s portion of the Interstate 70 (I-70) transcontinental highway in the US. This extends an earlier project between the Colorado Department of Transportation (CDOT) and Panasonic.
This marks Qualcomm’s first sortie into connected car silicon and also claims this is the first deployment of C-V2X technology in the US, even though at this stage it is just on trial. From CDOT’s point of view this is also an opportunity to compare C-V2X with its principal alternative for short range V2V or V2X communications to passing roadside equipment, called Dedicated Short-Range Communication (DSRC) – the 802.11p standard, used in the 5.9GHz DSRC band.
CDOT has already confirmed that it is agnostic over V2X technologies and is evaluating both DSRC and C-V2X at this stage when it is not clear which will end up the winner or even if both gain widespread deployment in different markets. Certainly, in the US automakers are divided, with Ford now in league with Qualcomm backing C-V2X, while Toyota and Lexus are in the DSRC camp, having promised to equip all vehicles sold in the US with this from 2021 and elsewhere by the mid-2020s.
There is greater weight behind DSRC in the US than elsewhere given that in March 2017 the country’s National Highway Traffic Safety Administration (NHTSA) announced it was considering requiring all new light vehicles to have DSRC. This was in the belief that the communications to, from and between vehicles enabled as a result would cut out about 80% of non-impaired crashes, meaning those involving drivers supposedly in full possession of their faculties and not under the influence of alcohol or drugs.
Of course, that has nothing to do with the choice of communications technology. In fact, the mobile industry is promoting C-V2X (and Qualcomm in particular) because it is part of the 3GPP standards groups and embraces LTE. It was finalized in June 2017 under Release 14 of those standards with 3GPP citing energy reduction through applications such as platooning as well as safety as advantages. Platooning saves money by shielding cars behind the leader from air resistance to some extent, exploiting the same slipstreaming principle as cycling teams do in races like the Tour de France.
Apart from mobile operators and equipment makers, C-V2X is backed by the majority of major automakers. Apart from Tesla and Toyota, the list includes Audi, BMW, Daimler and PSA. Volkswagen has a foot in both camps, reflecting partly perhaps its awareness that it needs to build as many bridges as possible in the US where the diesel emissions scandal broke. So while it is also backing C-V2X, it has announced it will start equipping some models with DSRC in 2019.
C-V2X seems to be winning the argument outside the US, with China set to become one of the first countries to deploy it commercially with some European ones on course to follow. One argument in its favor is that it will integrate better with cellular services since it is compatible with them. In truth though, C-2VX is really two separate protocols at present bolted together, presented as complementary modes. One is for direct communications between vehicles or with roadside infrastructure, or even other road users like cyclists and pedestrians, operating quite independently of cellular networks. The second mode for longer range network communications simply employs the conventional mobile network, say to receive information about road conditions and traffic.
The only real gain here at present is that the two modes are integrated into a single module. However mobile operators argue this will make it easier to integrate the various applications of V2V and V2X within C-2VX. They also argue that C-2VX will be fully aligned within emerging 5G networks and bring further advantages then, without clarifying exactly what they are or why these could not be achieved with 802.11p-based DSRC.
It is true that the 5G Automotive Association (5GAA) set up in 2016 to evaluate 5G as it emerges took part in a separate recent trial of Qualcomm’s fledgling C-2VX chipset alongside Ford and Audi in Washington DC. This showed how C-V2X communications can alert nearby vehicles to potential hazards when the driver’s view is obstructed, as at traffic junctions, as well as alerting other vehicles when turning or braking.
The battle between C-V2X and DSRC can almost be seen as a proxy war between cellular and WiFi. While C-V2X came out of 3GPP, DSRC emerged from wireless LAN as the IEEE 802.11p amendment for wireless access in vehicular environments in 2011. However, the two really overlap quite closely, both operating in the 5.9 GHz band which the FCC has stated it wants to share with connected vehicles in the US. It could be argued this dovetails better with WiFi but on the other hand cellular communications will be integral to both V2X and even V2V in future, so integration between short range and longer-range communications will be essential whichever of C-V2X and DSRC prevails.
DSRC has already been demonstrated for some connected car applications in the US, one being in June, 2017 when the Utah Department of Transportation successfully demonstrated a Transit DSRC system on SR-68 (Redwood Road) over 11 miles for communication with buses.
Qualcomm though has come right off the fence. While supporting both DSRC and C-2VX commercially it recently presented its own test results showing that the latter is far better optimized for the dense environments in which connected cars will operate. C-2VX is more able to cope with widely varying traffic conditions and vehicle speeds, as well as performing better with lower latency, according to Qualcomm.