As of present, we have a saturation of the transportation infrastructures due to the growing number of vehicles. This situation affects lives, particularly in the urban areas, while the need for people to move rapidly between different places increases.

The results are traffic congestion, accidents, transportation delays, and more vehicle emissions polluting the air. Many solutions were introduced to reduce the above-stated problems. Examples include the implementation of safety systems, such as safety belts and airbags, and the construction of more and better roads and highways.

Nevertheless, presently it is clear that building more roads to reduce traffic congestion is not the “right” solution, because it is very expensive while causing considerable environmental impacts, besides requiring a large space, which is an important limitation within urban areas. This is where emerging Intelligent Transportation Systems come into play. As conventional road vehicle systems depend almost entirely on human drivers, the modern road-vehicle systems will incorporate some intelligent systems technology to assist human operators.

Development Of Intelligent Transportation Systems In Various Countries

Generally, Intelligent Transportation Systems (ITS) are recognized as using information, communication, control, computer technology and other current technologies to establish a real-time, accurate and efficient transportation management system. Countries such as the USA, Japan and Germany pioneered in the research and development of ITS.

• United States

In the United States, Electronic Route Guidance System (EGRS) was the initial stage of the Intelligent Transportation System in the 1970s. In 1991s, United States’ congress enacted integrated surface transportation efficiency programs (ISTEA). TEA-21 (Transportation Equity Act for the 21^st Century) as a successor project ISTEA was formulated in 1997. Compared with ISTEA, TEA-21’s project scale and economic investment have a significant growth which can provide a strong guarantee for the development of ITS technology.

The ITS Strategic Research Plan (2010-2014) was promulgated by the United States Department of Transportation (USDOT) on December 8, 2009. This plan defines the strategic direction for the USDOT’s ITS research program for the next five years.

• Japan

Japan began their research in 1996 and created the world’s first vehicle information communications system (VICS), which has been available nationwide since 2003. But since 2003, traffic and congestion information in Japan has been generated increasingly through the use of probe vehicles, specifically by making VICS-enabled vehicles the probe vehicles themselves.

The technical architecture of Japan’s VICS, which was designed in the early 1990s was called “Version 1.0” of in-car navigation systems in Japan. Presently, they are looking into developing the Smartway, “Version 2.0” of the country’s state-of-the-art ITS service. Smartway finished its concept development in 2004 and was put into partial deployment in 2007.

Generally, Intelligent Transportation Systems (ITS) are recognized as using information, communication, control, computer technology and other current technologies to establish a real-time, accurate and efficient transportation management system. Countries such as the USA, Japan and Germany pioneered in the research and development of ITS.

• United States

In the United States, Electronic Route Guidance System (EGRS) was the initial stage of the Intelligent Transportation System in the 1970s. In 1991s, United States’ congress enacted integrated surface transportation efficiency programs (ISTEA). TEA-21 (Transportation Equity Act for the 21^st Century) as a successor project ISTEA was formulated in 1997. Compared with ISTEA, TEA-21’s project scale and economic investment have a significant growth which can provide a strong guarantee for the development of ITS technology.

The ITS Strategic Research Plan (2010-2014) was promulgated by the United States Department of Transportation (USDOT) on December 8, 2009. This plan defines the strategic direction for the USDOT’s ITS research program for the next five years.

• Japan

Japan began their research in 1996 and created the world’s first vehicle information communications system (VICS), which has been available nationwide since 2003. But since 2003, traffic and congestion information in Japan has been generated increasingly through the use of probe vehicles, specifically by making VICS-enabled vehicles the probe vehicles themselves.

The technical architecture of Japan’s VICS, which was designed in the early 1990s was called “Version 1.0” of in-car navigation systems in Japan. Presently, they are looking into developing the Smartway, “Version 2.0” of the country’s state-of-the-art ITS service. Smartway finished its concept development in 2004 and was put into partial deployment in 2007.

Smartway Cooperative Vehicle Highway System was developed based on Japan’s deployment of ITS experience. As shown in the overview of Smartway in Fig. 2, there are a lot of services that are provided by using a platform. Using 5.8 GHz DSRC technology, Smartway can provide visual information of road conditions ahead, traffic information through audio in a visual format and location, and contextually specific information to the driver. Smartway can warn drivers when they are coming across particularly accident-prone areas of a roadway, and uses a DSRC-enabled roadside unit to alert drivers on the main lanes of the presence of merging vehicles and sends appropriate warnings.

(Source: S. An, B. Lee and D. Shin, “A Survey of Intelligent Transportation Systems,” 2011 Third International Conference on Computational Intelligence, Communication Systems and Networks, 2011, pp. 332-337, doi: 10.1109/CICSyN.2011.76)

Key Underlying Technologies

There are several underlying technologies for ITS, such as:

1. Global Positioning System (GPS)
2. Dedicated-Short Range Communications (DSRC)
3. Wireless Networks
4. Mobile Telephony
5. Radio Wave or Infrared Beacons
6. Roadside Camera Recognition

Here, we will be deep-diving into how the above technologies are brought into the context of ITS.

• Global Positioning System (GPS):

Embedded GPS receivers are used in vehicles to receive signals from several different satellites to the position vehicle. This requires lines of sight to satellites, which can hold back the usage of GPS in downtown settings because of “urban canyon” effects. To accurately locate a position, a minimum of four geostationary satellites are required yet due to the tall buildings in certain environments, the number of satellites is less than four. This causes an effect, known as the ‘Urban Canyon Effect’, which makes the positioning less accurate. Location can usually be done with a limit of 10m. GPS is a core technology behind many in-vehicle navigation and route guidance systems.

• Dedicated-Short Range Communications (DSRC):

Dedicated-Short Range Communications (DSRC) is a one-way or two–way wireless communication channel that operates in the 5.8 or 5.9 GHz wireless spectrum and is specifically designed for automotive uses. DSRC is capable of two-way wireless communications between the vehicle and roadside equipment. It plays a key role in many Intelligent Transportation Systems, including vehicle-to-infrastructure integration, vehicle-to-vehicle communication, adaptive traffic signal timing, electronic toll collection, congestion charging, electronic road pricing, information provision, etc.

• Wireless Networks

Wireless networks are accessible to rapid communications between vehicles and the roadside, which is similar to technology commonly used for wireless internet access, however, they have a range of only a few hundred meters. Nevertheless, this range can be extended to pass information onto the next vehicle or node by each successive vehicle or roadside node. WiBro is increasingly in usage in South Korea, based on WiMAX technology, as the wireless communications infrastructure to transmit traffic and public transit information throughout its transportation network.

• Mobile Telephony

Standard third or fourth generation (3G or 4G) mobile telephone networks can be used to transmit information in the applications of ITS. There are advantages of mobile networks like wide availability in towns and along major roads. Additional network capacity may be required if vehicles are fitted with mobile networks, and network operators might need to cover these costs.

• Radio Wave or Infrared Beacons

Vehicle Information Communications System (VICS) from Japan uses radio wave beacons on expressways and infrared beacons on main roads to transmit real-time traffic information.

• Roadside Camera Recognition

Camera or tag-based schemes can be used for zone-based congestion charging systems, as well as for charging on specific roads. Cameras placed on roadways are used where drivers enter and exit congestion zones in such systems. The cameras utilize Automatic License Plate Recognition (ALPR) to identify vehicle license plates which are based on Optical Character Recognition (OCR) technology; the back-office servers assess and post charges to drivers for their use of roadways within the congestion zone. Moreover, it can pass the information digitally.

The Future Of Intelligent Transportation Systems

1. Involvement of IoV (Internet of Vehicle):

The current traffic operation strategies are mostly based on a centralized control algorithm. This will lead to a significant amount of computing resources when the scenarios are complicated. With the help of IoV technology, we can distribute parts of the decision task to each vehicle. By enhancing the information exchange between vehicles, a decentralized solution can be proposed, which provide efficient traffic operation services and ensure the scalability of the system.

2. Utilization of multiple-source data in ITS:

Compared to a single source, multiple sources can provide complementary data, and multi-source data fusion can produce a better understanding of the observed situation by decreasing the uncertainty related to individual sources. Furthermore, it’s significantly less expensive to install and maintain a suite of sensors. If one or more sensors are malfunctioning due to some failure, it will only decrease the penetration rate slightly and will have a small impact on the system performance. With the help of ITS, we can get real-time and multiple-sources traffic data. As a result, this will allow us to manage the transportation system more efficiently.

3. Automated driving:

The development of communication and sensing technology has fast-tracked the commercialisation of automated driving. Traffic operations will be affected by it. Aside from making automobiles safer, researchers are also developing ways for automated vehicle technology to reduce congestion and fuel consumption.

4. Security:

Electronic security is always a troubling question. While security measures for personal computers and internet communication were implemented largely as an afterthought, vehicle to vehicle (V2V) and vehicle to infrastructure (V2I) protocols have been developed with security implemented in the initial stages. Computer hackers may target ITS more generally, causing collisions and traffic disruptions or stealing of personal information. Overcoming these challenges might become the research focus in the future. The control strategy of the Cooperative Automated Vehicle (CAV) is considered a major prospect of ITS development. CAV can collect data from all transportation elements and cooperate with all of them to make the whole traffic system efficient. Different from the centralized operation approach in the traditional traffic operation system, CAV gives us a new perspective on the operation in a decentralised way.

Finally, Intelligent Transportation Systems improve transportation safety and mobility, reduces environmental impacts, promotes sustainable transportation development, and enhances productivity through the integration of advanced communication-based information and electronic technologies into the entire transportation system.