“Smart transportation” is an Internet of Things vertical application which integrates modern technologies and management strategies in transportation systems. It often includes multi-modal connected transportation systems, traffic sensors, integrated fare systems, advanced traffic signal systems, and automated tolls and fare collection. Elements of such systems influence daily operations across highways, public transportation and on-demand mobility while relying on information systems, new technologies, and automated and connected vehicle systems.
Ultimately, these applications are designed to help make future transportation systems not only “smarter” but also more efficient and accessible and safer. Innovations in “smart transportation” bring important benefits to cities, such as potentially increasing mobility, incentivizing transit ridership, providing mobility to underserved populations, and reducing congestion and air pollution. They also could help communities achieve important safety benefits, such as reducing automobile collisions, promoting driver, passenger and pedestrian safety, and giving drivers safety warnings and assistance. When the U.S. Department of Transportation (DOT) announced its “Smart City Challenge” in 2015 to help cities develop ideas for “smart transportation” systems, the response was overwhelming, with 78 cities submitting proposals. Columbus, Ohio, was chosen as the winner and has undertaken a number of smart transportation initiatives.
Automated vehicles have the potential to significantly transform transportation systems. These vehicles have on-board sensors, including radar, LiDAR and cameras, which detect activities around the vehicle. Data from the sensors, combined with detailed digital mapping, allows the vehicle to take over some driving functions. There are five levels of automation, ranging from limited control of the forward motion of the vehicle (i.e., adaptive cruise control) to full automation, where a human driver is not needed. Lower levels of automation are available in many new cars today, but full automation is still a number of years away. While automation systems are being designed to operate on today’s infrastructure, automated vehicles will be more effective if agencies improve paint stripes and roadway signage to be tailored to automated vehicles. This could include roadway improvements such as thicker lane markings and standardized signage that does not fade.
Smart transportation relies on telecommunications to allow communication between vehicles, the infrastructure and traffic management agencies, and to facilitate real-time data collection and analytics.
In 1998, Congress enacted the Transportation Equity Act for the 21st Century (TEA-21). This legislation allocated spectrum on a dedicated short-range band, known as the 5.9 GHz band, for Intelligent Transportation Systems (ITS). This dedicated band, often referred to as the “Safety Band,” is used by Dedicated Short Range Communication (DSRC) systems to send and receive vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I) and vehicle-to-pedestrian (V2P) communications, collectively known as vehicle-to-everything (V2X). These “connected vehicle” (CV) safety applications seek to reduce automobile collisions, promote driver, passenger and pedestrian safety, and save lives by providing safety warnings and assistance to drivers.
Connected vehicle wireless systems generally have a range of about 1,000 feet and do not depend on “line-of-sight” communications to be effective. CV systems are not affected by snow, fog or rain. In essence, the car and its driver can learn things about the transportation environment that generally cannot be seen. This is in contrast to automated vehicles, which gain information from on-board sensors. Automated vehicles will not necessarily be connected, and connected vehicles will not necessarily be automated, but we anticipate that in the future many vehicles will have both systems.
In order for V2I systems to work effectively and communicate with transportation infrastructure such as traffic signals, agencies will need to install wireless communications systems and software along the roadway.
An additional connected vehicle technology has recently emerged: Cellular-V2X (C-V2X). While DSRC is based on communications using Wi-Fi standards, Cellular-V2X (C-V2X) is based on 4G cellular technology. C-V2X is not yet allowed to use the 5.9GHz safety spectrum for regular operations, but the FCC is proposing to allow its use of the spectrum (see page 14).
DSRC, C-V2X and 5G Systems
DSRC is a short-range wireless communication system, similar to Wi-Fi, that operates on the 5.9 GHz radio spectrum. It was designed specifically to allow vehicles to quickly communicate with each other and with the infrastructure. It enables data and systems to interface by sending and receiving various bits of information without using cellular or other infrastructure.
C-V2X is a 4G cellular-based technology that provides direct communications between vehicles, vehicles and infrastructure, vehicles and other road users, and vehicles and cellular communications providers’ mobile broadband networks. However, the technology is not compatible with DSRC-based operations.
5G, or 5th Generation Wireless, is the newest mobile network for cellular communication. When fully mature it promises a new wireless system that is deployed around the world, offering faster speeds, greater capacity and better reliability compared to previous cellular networks. At some point, it may also provide communication for connected vehicles.
The Signal Phase and Timing (SPaT) Challenge (Challenge) was created by the V2I Deployment Coalition, led by the American Association of State Highway and Transportation Officials (AASHTO), the Institute of Transportation Engineers and the Intelligent Transportation Society of America, with the goal of implementing DSRC communications at a minimum of 20 signalized intersections in each state by January 2020. Using the 5.9 GHz band, the Challenge seeks to provide a starting point for deploying DSRC technologies and helping government and industry gain operational experience along the way. The DOT reports that CV deployments are underway in 25 states, from California to New Hampshire. These efforts are driven in part by the SPaT Challenge.
A SPaT message contains information about the status of traffic signal phases, including whether emergency vehicles are preempting the signal or pedestrians have requested to cross. Combined with a message that includes information on intersection geometry and defines the various lanes in the intersection, SPaT is broadcast to connected vehicles. In turn, the vehicle broadcasts a Basic Safety Message (BSM) to the roadside, anonymously indicating various aspects of vehicle behavior, including the speed, direction, braking activity and windshield wiper activity. This information can be used by the vehicle to avoid running a red light or hitting an oncoming vehicle. It can also be used by traffic managers to adjust signal timing without deploying personnel to the field, detect incidents and give safety warnings to drivers about potential hazards. Additionally, SPaT can prioritize extended green lights for certain vehicles such as transit buses and snowplows.
Ohio and Utah are considered leaders in testing and developing CV technologies. Their testing and deployment efforts were studied across transportation modes.
The Ohio the Department of Transportation (ODOT) is leading Ohio’s smart transportation efforts through the state’s DriveOhio initiative created by executive order in 2018 and refined by a subsequent order in 2019. Technologies being deployed involve DSRC systems, vehicle onboard units and unmanned aerial systems (i.e., drones). The ODOT also received a $7.5 million federal grant to help facilitate testing and development of CVs through multi-pronged demonstrations focusing on rural environments, cooperative automation and robust data collection with the goal of helping develop effective and informed smart transportation policies.
- 33 Smart Mobility Corridor
This 35-mile segment on U.S. Route 33 will serve as the proving ground for smart mobility technology, including connected and autonomous vehicle technologies. The ODOT and local governments will equip the highway with high-capacity fiber-optic cable and roadside sensors. The data collected from this project will improve the accuracy and timeliness of traffic counts, weather and surface conditions, and incident management.
- Connected Marysville
A subset of the 33 Smart Mobility Corridor project, the city of Marysville upgraded 27 traffic signals by using DSRC systems to manage signal timing, detect pedestrians and prevent collisions. By installing onboard units in at least 1,200 vehicles, Marysville expects to create a “real-world environment where companies, governmental agencies and academia can develop and test smart technology…” according to the Connected Marysville website. The data will help design new CV technologies and future applications that may help drivers make better decisions behind the wheel.
- U.S. Route 33: Traffic Monitoring
A three-year project is underway using drone technology to monitor traffic conditions and flow along a section of U.S. Route 33. Once the project is finished, the results of the study will help inform what may be needed to create a “low-altitude air traffic management system.” The results of this effort will help determine if and how unmanned aircraft can be safely operated.
- I-90 Lake Effect Corridor
Sixty miles of I-90, situated on a section of highway with limited visibility caused by adverse “lake-effect” weather conditions, will be equipped with DSRC units and will also test wireless systems designed to send and receive data. From a combination of data collection and variable speed limit signs, the overall management of the roadway can be improved, including a reduction of crashes and fatalities. Additionally, the ODOT will use this information to inform real-time changes when deciding to reduce speed limits due to inclement weather or other high-impact events.
Utah’s Department of Transportation (UDOT) deployed CV technologies to improve the quality and service levels of its bus systems and snow removal operations. Specifically, Transit Signal Priority is being used to hold green lights longer or shorten the timing of red lights. This effort seeks to improve bus flow, mobility and operational efficiency.
- Redwood Road Connected Vehicle Project: DSRC is deployed at 24 intersections and in 10 buses operated by the Utah Transit Authority. The goals of this project were twofold: 1) to give priority to buses entering intersections that were behind schedule and 2) improve transit schedule reliability. Since November 2017, the results have shown a 6% increase in scheduled bus system reliability and a decrease in the variability of bus arrivals at stops. Following the success of this project, a DSRC-based transit signal priority system was installed on the UVX Bus Rapid Transit project in Orem and Provo, Utah, in 2018, and is being planned for two more routes in Salt Lake and Utah Counties.
- Snowplow PreEmption Project: DSRC is deployed at 55 intersections and in 46 snowplows. Given the success shown on buses, the UDOT initiated a project to outfit snowplows with the same DSRC technology. Some stakeholders anticipate that if snowplows receive signal preemption on key routes, then those roads will be cleared of snow and ice sooner. By doing so, this will bring safety benefits such as fewer crashes. Plow efficiency is also improved.
- Panasonic “Smart Roadways” Partnership: In June 2019, the UDOT announced a five-year partnership with Panasonic to develop the nation’s most advanced network of “smart roadways.” This partnership will allow the UDOT to accelerate development of a statewide system to collect, monitor and share data between vehicles, infrastructure, roadways and traffic managers in real-time environments. This effort will build on the UDOT’s existing framework for CV technologies by enabling insights into critical events such as crashes, inclement weather events and stalled vehicles. Traffic managers will be able to use this information to alert CV drivers in real-time with alternate routes, delay times and other helpful information. V2X equipment (DSRC and C-V2X) has already been installed in 69 roadside locations and in 35 UDOT fleet vehicles.
Spotlight: Salt Lake City
Salt Lake City’s smart community effort is aided through its partnerships with Rocky Mountain Power (RMP), Park City, Breathe Utah, Fourth Mobility, Giv Development, Idaho National Laboratory, Maverik, New Flyer, Salt Lake City International Airport, the U.S. Department of Energy, Uber, Utah Clean Cities Coalition, University of Utah, Utah State University and the Utah Transit Authority (UTA).
Salt Lake City’s Goals:
- Promote adoption of electric transportation.
- Enhance access to renewable energy.
- Reduce city emissions.
- Enhance energy efficiency.
What Makes Salt Lake City Smart?
Smart Transportation—Improves safety and mobility, reduces carbon footprint, and provides greater access to services. RMP will use $4 million awarded by the U.S. Department of Energy and $10 million from its Sustainable Transportation and Energy Plan to accelerate the adoption of plug-in electric vehicles in the greater Salt Lake City area by developing electric highway corridors, advancing workplace charging, and incentivizing fleet conversions.
Salt Lake City International Airport will deploy all-electric ground support equipment and infrastructure and install more than 100 electric vehicle charging stations at short- and long-term parking lots as part of a $3 billion expansion.
Salt Lake City is partnering with RMP, UTA and the University of Utah to deploy five electric buses operating between the downtown transit hub and the university.
Mobility on Demand
Mobility on Demand (MOD) is a concept where travelers can access multiple transportation services over a single digital interface. A traveler could book a shared ride (such as Uber or Lyft) to a train station, buy the train ticket and reserve an electric bike at the other end of the train ride in one place. This concept, along with all of the components of Mobility as a Service (MaaS)—shared rides, bike and scooter rentals—are integral to the development of smart communities. These systems all require pervasive access to digital communications systems.
Low-speed, automated vehicle shuttles are being tested in a variety of locations, including California, Colorado, Delaware, Florida, Minnesota, Texas, Utah and Virginia. These vehicles follow fixed routes, providing transportation within senior communities, office parks, shopping complexes and university campuses. They have no human driver but have attendants on board who can take over the driving function if needed. One potential use of these shuttles is to transport people through the first mile or last mile, getting them to and from bus or train stations. Smart communities may include these types of transportation systems to improve mobility options.
While many of the activities associated with smart transportation, including connected, automated and electric vehicles, are being driven by the private sector, state and local actions can support, encourage or inhibit these activities. Tax policies or financial incentives will influence the deployment of electric vehicles. Zoning regulations and transportation planning influence the use of curbs by shared ride services and non-motorized transportation. State regulations will dictate the consistent testing and deployment of automated vehicles and will facilitate the communication systems necessary for connected vehicles.
Transportation and Telecommunications Nexus
In January 2020, the DOT announced another initiative using the 5.9 GHz band for “technologies to improve safety for the traveling public and first responders.” At the time of the announcement, Transportation Secretary Elaine Chao was quoted as saying, “These systems will use the 5.9 Gigahertz Safety Band of spectrum currently allocated for use in transportation systems. We believe it is very important to retain this bandwidth for this purpose, and the Department is actively advocating the FCC to do so.” Specific details about this program, including selection of sites, are still pending.
The DOT announced in May 2020 that there are 23,002 planned and operational vehicle-based DSRC devices, prompting criticism that the number of vehicles with DSRC devices has failed to reach the critical mass necessary to be effective. While General Motors has installed DSRC units on select Cadillac models, Ford announced its intention to install C-V2X equipment on all new vehicles starting in 2022. Other automakers will likely follow suit installing C-V2X equipment. While CV technologies have continued to advance over the last two decades, innovations in broadband and increased demand for Wi-Fi may force DSRC operations to share or move off the 5.9 GHz band entirely.
Over the past few years, the telecommunications industry and other advocates have argued that the 5.9 GHz spectrum, reserved for DSRC and also referred to as the safety spectrum, is being underutilized. In December 2019, the FCC proposed to create sub-bands within the 5.9 GHz band to allow unlicensed operations like Wi-Fi to operate in the lower 45 megahertz of the band (5.850-5.895 GHz) and reserve the upper 30 megahertz of the band (5.895-5.925 GHz) for ITS. The proposal sought comments on allotting space for both DSRC and C-V2X in the upper 30 megahertz of the band. In the rulemaking notice, the FCC noted that DSRC and C-V2X “are mutually incompatible (and thus cannot both be authorized to operate on a single channel without causing harmful interference).” Uncertainty surrounding the safety spectrum has caused some major automobile manufacturers, including Toyota, to pause their connected vehicle plans.
One concern about reducing the safety spectrum is the potential for wireless interference from non-transportation communications. A preliminary report by the National Highway Traffic Safety Administration (NHTSA) recently concluded that repurposing the 5.9 GHz band for non-transportation purposes may create harmful interference to the point where safety benefits could be reduced or eliminated. Transportation stakeholders—agencies, automakers and suppliers—have been largely united in requesting the FCC to leave the safety spectrum intact. The AASHTO has expressed opposition to using the 5.9 GHz band for non-transportation purposes, arguing both that the current band should be reserved for transportation safety purposes and that DSRC is the only proven technology that will enable the development of a CV environment.
In its filed comments, the NCTA—The Internet & Cable Association argues that “Wi-Fi carries a significant—and growing—percentage of overall traffic online,” particularly as 5G develops. Furthermore, “this ever-increasing demand already threatens to outstrip the nation’s unlicensed spectrum capacity, which would result in significant congestion.” NCTA views the 5.9 GHz band as ideal to help facilitate the development of the next-generation Wi-Fi standard, Wi-Fi 6, and notes that “no automaker has current plans to deploy DSRC radios in new vehicles.” NCTA warns that if the FCC does not repurpose the 5.9 GHz band, “C-V2X cannot deploy in the first place given the technology- and standard-specific rules governing the band.”
The Wi-Fi Alliance filed comments disputing claims that opening up the 5.9 GHz band to Wi-Fi use will create interference for the operation of ITS.
A decision by the FCC is expected in late 2020.
In 2017, NHTSA announced a proposed rulemaking to mandate all new light-duty vehicles be equipped with V2V technology capable of transmitting over DSRC. These provisions would gradually take effect over three years. At the time, NHTSA projected that the mandate would start at 50% of the new vehicle fleet in 2021, increasing to 75% in 2022 and 100% in 2023. NHTSA studies indicated that these systems would mitigate 83% of non-impaired crashes. However, NHTSA has yet to initiate any next steps and the rulemaking process has halted. In 2015, the DOT announced funding awards for three Connected Vehicle Pilot Deployments in New York City, Tampa, Fla. and Wyoming, respectively. With a $42 million federal investment, these three sites have deployed significant infrastructure elements and developed numerous V2I software applications. The DOT continues to be engaged in these projects, solving deployment issues and sharing lessons learned.
The DOT is also continuing to encourage development of automated vehicle technologies. Specifically, in the fall of 2019, the DOT awarded a number of discretionary grants as part of its Automated Driving Systems (ADS) Demonstration Grant program. As part of these awards, millions of dollars were directed toward projects that focused on the safe integration of ADS into work zones by examining connectivity, visibility and high-definition mapping technologies. In Iowa, the state DOT received a $7 million ADS grant to connect rural, transportation-challenged populations using a mobility-friendly ADS built on a commercially available platform. The University of Iowa will study automated vehicles and conduct various safety demonstrations. The goal of the grant is to help bring safe, driverless transportation services to rural areas in the state.
Additionally, the DOT’s largest discretionary grant program, the Better Utilizing Investments to Leverage Development, or BUILD Transportation Discretionary Grant program, provides federal grants for road, rail, transit and port projects that promise to achieve national objectives. Previously known as Transportation Investment Generating Economic Recovery, or TIGER Discretionary Grants, Congress has dedicated nearly $7.1 billion for 10 rounds of National Infrastructure Investments to fund projects that have a significant local or regional impact.
Recently, a number of BUILD grant awards have funded CV projects. In 2018, the DOT funded three specific projects all with a major focus on CVs. The Colorado Department of Transportation (CDOT) received $20 million, featuring an expansion of deployed CV technology on seven highway segments, consisting of 455 miles, as well as fiber installation on three corridors covering 319 miles. The goal is to improve the safety of drivers and to inform CDOT of crashes or hazards on the roads using Infrastructure-to-Vehicle (I2V) communications to send safety and mobility-critical messages directly to the driver and CDOT.
A second project in Jacksonville, Fla., received $25 million that includes a particular focus on connected traffic signals allowing vehicles to communicate with existing infrastructure, thereby improving traffic flow and mobility. The third project is a $5 million award to Las Vegas, to help the city roll out its automated and connected vehicle service.
In January 2020, the DOT released the fourth version of its automated vehicle guidance, Ensuring American Leadership in Automated Vehicle Technologies: Automated Vehicles 4.0 (AV 4.0). While the document is primarily focused on automation, it also provides a detailed description of federal government efforts to promote use of CVs.