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There has been heated debate about the 5.9-GHz frequency band dedicated to cooperative intelligent transportation systems (C-ITSs). Spectrum is limited, and the free bands at 2.45 GHz are becoming crowded. Because of this, operators in the European Union seek access to the band for fifth generation (5G), while, in the United States.
Wi-Fi wants access to the band. However, 5G is not yet fully defined, implying that it may or may not include Wi-Fi. The C-ITS technology, termed dedicated short-range communications (DSRC) in the United States and ITS-G5 in Europe, is standardized but not deployed.
In 2009, it seemed that DSRC and cellular technology were two complementary technologies, one best for short distances and the other for long ones. It seemed equally complex and unnecessary to route long-range messages through a vehicular ad hoc network (VANET), as it seemed to take a detour via a base station for ranges when the receiving vehicle was located closer.
Furthermore, it seemed dangerous and absurd to rely on the presence of base stations and cellular coverage for safety-critical communication in emergency situations. Recently, however, cellular vehicle-to-everything (C-V2X) has relaxed the constraints on making detours around the base stations and now allows out-of-coverage communication directly between two vehicles.
Are DSRC and C-V2X now two competing technologies? Regarding spectrum, they quite obviously are. What was less clear to me in 2009, however, was that they also have fundamentally competing business models. The entire cellular industry relies on charging money for using base stations and frequency spectrum.
The vehicle industry got 75 MHz in the United States free of charge, whereas the telecommunications (telecom) industry in Sweden paid up to US$11 million (€9.3 million) for 20 MHz during the fourth-generation auction in 2011. Is it because of this that DSRC has been accused of being a security risk, and that the cable industry has suggested completely forbidding it?
The telecom industry has taken a different approach and has instead joined forces with the vehicle manufacturers of the 5G Automotive Association, but still with the main agenda of showing that 5G can do everything that DSRC can do and more. Can it? In terms of technology, yes, absolutely—but the business model prevents it.
What would happen if DSRC were made mandatory on all light vehicles, as suggested in the United States? Just a few years back, my cell phone was very seldom on Wi-Fi, and the use of femtocells and HetNets was being enthusiastically discussed everywhere.
Today, my cell phone is basically always on Wi-Fi, and I have happily bought an iPad without cellular capabilities. We use Wi-Fi at home and in the office, at restaurants and coffee shops, with some cities even planning to offer Wi-Fi free to their citizens. In Sweden, we have free Wi-Fi on most of our trains (and mostly it works, even though the access point rides on the train, communicating via cellular base stations).
The only place I do not have Wi-Fi is in the car, but now a Wi-Fi-type standard could be mandated on all light vehicles. Furthermore, research is finding ways to pinpoint location without the global positioning system (GPS) or cellular base stations, and delay-tolerant content-based routing algorithms are being developed. This could be used not only for vehicles but for ad hoc communications between people who are out of Wi-Fi coverage.
Full article: IEEE Vehicular Technology Magazine, Volume 13, Number 1, March 2018 | 
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