June 28Updated December 17, 2019
Smart Cars and Trucks: Spectrum Use for Vehicle Safety
Background
Increasing the autonomy of cars and trucks is seen as an
effective way to reduce the 94% of vehicle-related
accidents that are caused by human error. While some
semiautonomous safety technologies, such as automatic
braking and adaptive cruise control, are in use today,
autonomous safety technologies under development would
require cars and trucks to communicate with each other
(vehicle-to-vehicle, or V2V) and with their surroundings
(vehicle-to-infrastructure, or V2I). V2V communication is
expected to reduce the number of accidents by improving
detection of oncoming vehicles and providing driver
warnings. V2I communication is expected to help highway
operators monitor and manage traffic and provide drivers
with information such as weather and traffic conditions.
These technologies are part of a congressional mandate to
invest in and advance a broader set of intelligent
transportation systems to improve traffic flow and safety.
For vehicles to communicate wirelessly, they need access to
radio waves, or radio frequencies. In the United States, the
Federal Federal
Communications Commission (FCC) manages
commercial commercial
use of the radio frequency spectrum, and
allocates spectrum
for specific uses. In 1999, the FCC
allocated allocated 75 megahertz
(MHz) in the 5.9 gigahertz (GHz) band to Dedicated ShortRange Communications (DSRC) uses. DSRC technologies,
installed in cars and trucks and on roadways, enable V2V
and V2I communications.
Integrating DSRC technologies in vehicles and on
roadways is in its early stages. Meanwhile, the proliferation
of cell phones and other devices has increased demand for
spectrum, and a competing technology, Cellular Vehicle-toEverything (C-V2X), has emerged as an alternative to
DSRC for vehicular communications.
consider spectrum needs for transportation, including the
DSRC wireless standard. The goal of the initiative was to
leverage technologies to improve traffic flow and safety.
From FY2003 through FY2014, DOT provided about $570
million for research, development, and testing of DSRC
technologies. In 2015, it awarded $43 million to three pilot
sites (with an additional $9 million in local matches):
Safety in a large metropolitan area. The New York
City Department of Transportation is outfitting 8,000
taxis, buses, and sanitation vehicles with DSRC safety
devices to demonstrate connected-vehicle capabilities
focused on alerting drivers to potential crashes and
reducing accidents with pedestrians.
Interstate routes and commercial vehicles. During
severe winter weather along I-80 in Wyoming, DSRC
technologies are used to notify cars and trucks of
disabled vehicles. Vehicles rebroadcast the warning.
The goal is to prevent weather-related crashes.
Mid-sized urban area. Cars, buses, and pedestrians
are part of a DSRC pilot in downtown Tampa, FL, that
alerts drivers to reduce speeds when approaching heavy
traffic, when forward collisions may be imminent, and
where intersections are unsafe.
In addition to these pilot projects, several manufacturers in
the United States and Europe have begun integrating DSRC
technologies into cars and trucks; truck platooning (the
linking of multiple trucks into a convoy through V2V
communications) has been demonstrated on U.S. highways;
and additional DSRC deployments are under wayunderway in more
than two dozen states (see Figure 1.)
Figure 1. DSRC Deployments
In May 2019, the FCC announced it would consider
whether the 5.9 GHz band should (1) remain dedicated to
DSRC technologies, (2) be allocated to C-V2X, (3) be
allocated to automotive communications technologies
generally, or (4) be shared with wireless devices. The
FCC’s decision has important competitive implications for
the automotive, electronics, and telecommunications
industries, and may affect the availability of safety
technologies and the path toward December 2019, the FCC proposed rules that would
reallocate the lower 45 MHz of the 5.9 GHz band for
unlicensed use (e.g., Wi-Fi), and allocate the remaining 30
MHz for transportation and vehicle-related use. Of the 30
MHz, the FCC proposed to grant C-V2X exclusive use of
20 MHz of the segment. It is seeking comment on whether
the remaining 10 MHz should remain dedicated to DSRC or
be dedicated to C-V2X. The FCC commissioners noted that
DSRC has evolved slowly and has not been widely
deployed, and the rules are intended to ensure the spectrum
supports its highest and best use. This decision has
competitive implications for the automotive, electronics,
and telecommunications industries, and may affect the
availability of safety technologies and the path toward
vehicle automation.
DSRC
In 1998, the Transportation Equity Act for the 21 st Century
(TEA-21; P.L. 105-178) directed the FCC, in consultation
with the U.S. Department of Transportation (DOT), to
consider spectrum needs for transportation, including the
DSRC wireless standard. The goal of the initiative was to
leverage technologies to improve traffic flow and safety.
Source: CRS, based on data from Volpe National Transportation
Systems Center (DOT), May 2019.
Notes: DOT has 52 operational projects and 35 more planned,
including more than 26,000 devices deployed on vehicles in urban,
rural, and suburban settings.
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Smart Cars and Trucks: Spectrum Use for Vehicle Safety
C-V2X
In addition to research on DSRC, some automakers and
telecommunications and technology companies continue to
explore other vehicle connectivity options. The 3rd
Generation Partnership Project, a standards organization for
global wireless networking, created the C-V2X standard in
2017. Like DSRC, C-V2X can operate independently from
the cellular network for V2V and V2I communications. CV2X can also connect to cellular networks and is expected
to be able to use future 5G networks. 5G, when fully
deployed, is expected to provide high-speed, low latency
(i.e., reduced lag time) services needed for autonomous
vehicles, allowing information between vehicles and
infrastructure to be shared almost instantaneously.
The 5G Automotive Association (5GAA), a consortium of
automakers, technology companies, telecommunication
providers, standards bodies, and others, supports C-V2X.
The 5GAA asserts that C-V2X performs better than DSRC
in testing and is emerging as the global standard. In
November 2018, 5GAA asked the FCC for a portion of the
5.9GHz band to develop and deploy C-V2X.
Testing of C-V2X has so far been limited. DOT plans to
begin tests in three states in summer 2019.
Source: CRS, based on data from Volpe National Transportation
Systems Center (DOT), May 2019.
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Smart Cars and Trucks: Spectrum Use for Vehicle Safety
Notes: DOT has 52 operational projects and 35 more planned,
including more than 26,000 devices deployed on vehicles in urban,
rural, and suburban settings.
Proposed DOT Standard
At the end of the Obama Administration in January 2017,
the National Highway Traffic Safety Administration
(NHTSA) proposed a new federal safety standard that
would require all new light vehicles—passenger cars, sportutility vehicles, and pickup trucks—to be equipped with
DSRC technology by 2023. Proponents say that this
mandate is necessary to ensure compatibility and
connectivity across all vehicles and systems; DOT
projected . DOT projected
that implementing it could prevent more than
1,000
fatalities annually. The Trump Administration has
taken no
further action on this proposal; it has stated that
, stating that DOT should remain technology-neutral rather than mandate
a specific technology. It encourages the development of
multiple technologies that utilize the 5.9 GHz band for
transportation safety.
Policy Considerations
In 2012, Congress directed the FCC to determine whether
the 5.9 GHz band could be shared to support unlicensed
devices such as cordless phones, wireless speakers, and WiFi devices (P.L. 112-96, Title VI). The FCC is conducting
extensive testing to determine whether these devices would
cause interference with DSRC technologies.
In May 2019, FCC Chairman Ajit Pai called for
reexamination of the 5.9 GHz band. Several FCC
commissioners have supported this move, noting that the
pace of deployment of DSRC technologies left spectrum
underutilized while consumer demands for spectrum are
increasing, and that new technologies surpassing DSRC’s
capabilities need access to spectrum to develop.
Motor vehicle, telecommunications, and technology firms
have both competing and overlapping interests in the
outcome. Some automakers have invested in DSRC and
have plans to include it in their fleets: Cadillac markets a
model now that includes it. Ford, Volkswagen, and Toyota
planned to follow suit, but have paused deployment due to
the lack of a federal standard and spectrum uncertainties,
and also see benefits in C-V2X. Telecommunications
providers stand to benefit from C-V2X, as it relies in part
on cellular networks and has the potential to increase their
customer base and revenues. Telecommunications
technology companies, such as Qualcomm, which makes
both DSRC and C-V2X chips, stand to benefit from an
expanded connected car market.
DSRC advocates, such as the Safety Spectrum Coalition,
which includes the Association of Global Automakers and
the American Trucking Associations as well as many state
departments of transportation, argue that millions of dollars
have been invested in DSRC and that the technology has
been thoroughly tested and is currently being deployed.
They argue that 5G deployment is years away in many
areas, so the benefits of C-V2X will take years to arrive.
Both DSRC advocates and 5GAA agree that the 5.9 GHz
band should remain dedicated to vehicle safety and other
intelligent transportation uses and should not be made
available for other purposes.
While the issue may be framed as a choice between DSRC
and C-V2X, these two technologies could coexist. The
Colorado Department of Transportation states that its
intelligent transportation system, RoadX, can accept and
transmit V2V and V2I information on both DSRC and
cellular platforms; in time, vehicles and roadside
infrastructure may be able to communicate under both
standards.
The Coalition for Safety Sooner—comprising 15 state
DOTs and other state highway authorities—says it is not in
the public interest to delay the deployment of currently
available safety technologies while waiting for other
technologies to emerge. On the other hand, the Wi-Fi
Alliance, whose members include major electronics
companies such as Apple, Cisco, and others, along with
consumer groups and wireless internet service providers, is
urging the FCC to complete the interference testing before
adding new users to the band. These groups argue that
sharing the band with unlicensed devices, including Wi-Fi
devices, will expand public access to broadband.
The challenge for policymakers is balancing the interests of
multiple stakeholders: investors in DSRC who committed
funding to develop car and truck safety technologies and
other intelligent transportation systems; consumer safety
advocates and others who want currently available
technologies to be diffused quickly; potential users of
expanded Wi-Fi services; C-V2X advocates who are eager
to deploy the next generation of vehicle safety technologies;
and the nation at large, which could benefit from expanded
deployment of technologies that would improve vehicle
safety, make roadways more efficient, and provide the
economic gains that often accompany the development of
new technologies.
Bill Canis, Specialist in Industrial Organization and
Business
Jill C. Gallagher, Analyst in Telecommunications Policy
https://crsreports.congress.gov
IF11260
Smart Cars and Trucks: Spectrum Use for Vehicle Safety
remain technology-neutral. Instead, the Administration
states that the 5.9 GHz band should remain dedicated to
vehicle safety, but should be open to multiple technologies.
New Technologies
As governments and industry were deploying DSRC, new
wireless technologies emerged with their own spectrum
needs. These include Wi-Fi and C-V2X.
Wi-Fi
In 2012, Congress directed the FCC to determine whether
the 5.9 GHz band could be shared to support unlicensed
devices such as cordless phones, wireless speakers, and WiFi devices (P.L. 112-96, Title VI, Section 6406). In
response to a July 2016 FCC Public Notice seeking
comments, some commenters proposed that all users share
the entire 75 MHz band, while others proposed that DSRC
safety-of-life applications have a separate segment. The
FCC is conducting testing to determine whether Wi-Fi uses
could cause interference with DSRC technologies. In a
December 2019 report, DOT stated that “channel test
results showed the potential for cross-channel interference,
having an impact on DSRC performance,” which likely
informed the FCC decision to assign spectrum to each user.
C-V2X
Working through the 3rd Generation Partnership Project, a
standards organization for global wireless networking,
some automakers and telecommunications and technology
companies created the C-V2X standard in 2017. Like
DSRC, C-V2X can operate independently from the cellular
network for V2V and V2I communications. C-V2X can
also connect to cellular networks and is expected to be able
to use future 5G networks. 5G, when fully deployed, is
expected to provide high-speed, low-latency (i.e., reduced
lag time) services needed for autonomous vehicles,
allowing information between vehicles and infrastructure to
be shared almost instantaneously.
The 5G Automotive Association (5GAA), a consortium of
automakers, technology companies, telecommunication
providers, standards bodies, and others, supports C-V2X.
The 5GAA asserts that C-V2X performs better than DSRC
in testing and is emerging as the global standard. In 2018,
5GAA petitioned the FCC for spectrum in the 5.9 GHz
band to develop and deploy C-V2X. Testing of C-V2X has
so far been limited to select highways in a few cities.
Policy Considerations
The reallocation of spectrum may encourage investment in
certain technologies and priorities and disinvestment in
others. Congress may wish to consider whether reallocating
the 5.9 GHz band would advance national priorities and
best serve the public interest.
In the debate leading up to the decision, DSRC advocates,
such as the Safety Spectrum Coalition, which includes the
Association of Global Automakers and the American
Trucking Associations as well as many state departments of
transportation, contended that DSRC should continue to be
supported, noting that millions of dollars have been
invested. The coalition maintains that the technology has
been thoroughly tested and deployed, is improving highway
safety, and may be able to co-exist with C-V2X.
The Coalition for Safety Sooner—comprising 15 state
DOTs and other state highway authorities—argued that it is
not in the public interest to delay the deployment of
currently available safety technologies (e.g., DSRC) while
waiting for other technologies (e.g., C-V2X, 5G) to emerge.
Automakers took different positions based on their differing
technology plans. Cadillac has already included DSRC in
some models, so any loss of DSRC spectrum may affect its
connected car plans, investments, and services. Volkswagen
and Toyota had paused DSRC deployment due to the lack
of a federal standard and spectrum uncertainties, and also
because they saw benefits in C-V2X; the reallocation of
spectrum for C-V2X may drive these companies to invest in
C-V2X. Ford had already announced it would deploy CV2X in its new vehicles in 2022; thus the reallocation of
spectrum for C-V2X would likely benefit Ford.
While the debate was framed as a choice between DSRC
and C-V2X, DSRC advocates, 5GAA, transportation
agencies, and safety advocates agreed that the 5.9 GHz
band should remain dedicated to vehicle safety uses and
should not be made available for other purposes. In
contrast, the Wi-Fi Alliance, whose members include major
electronics companies such as Apple and Cisco, along with
consumer groups and wireless internet service providers,
argued for the spectrum to be shared between transportation
and Wi-Fi users. These groups argued that sharing the band
with unlicensed uses (e.g., Wi-Fi) would expand public
access to broadband and better serve the public interest.
Telecommunications providers and technology firms stand
to benefit from more spectrum for C-V2X and Wi-Fi. CV2X relies in part on cellular networks and has the potential
to increase their customer base and revenues. Wi-Fi enables
interconnection of devices to telecommunication networks,
and is needed to support new 5G networks and services.
The challenge for policymakers is balancing the interests of
multiple stakeholders: investors in DSRC who committed
funding to develop car and truck safety technologies and
other intelligent transportation systems; consumer safety
advocates who want currently available technologies to be
diffused quickly; potential users of Wi-Fi services,
including consumers and telecommunications firms seeking
to deploy 5G networks; C-V2X advocates eager to deploy
the next generation of vehicle safety technologies; and the
nation at large, which could benefit from the deployment of
new technologies that would improve vehicle safety, make
https://crsreports.congress.gov
Smart Cars and Trucks: Spectrum Use for Vehicle Safety
roadways more efficient, and yield economic gains that
often accompany the development of new technologies.
Jill C. Gallagher, Analyst in Telecommunications Policy
IF11260
Bill Canis, Specialist in Industrial Organization and
Business
Disclaimer
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