A key part of ITS or intelligent transportation systems is data transmission, which can be done via various communication standards and must be supported with robust and high-quality equipment.
A key part of ITS or intelligent transportation systems is data transmission, which can be done via different communication standards and must be supported with robust and high-quality equipment.
Intelligent transportation systems have become a more popular and widespread phenomenon in cities across the globe.
As mentioned,
ITS is all about data and its generation and transmission. For example, inductive loop sensors generate and transmit data on vehicle flow; CCTV systems transmit video about various road situations; and parking sensors inform operators of the number of available parking in the area. How this data should be transmitted securely and reliably, then, is critical.
ITS data communication
ITS data can be transmitted under various communication standards which include the following.
GNSS
Global navigation satellite systems (GNSS) allow small electronic receivers, including vehicle onboard units and drivers’ smart devices, to determine their location to high precision. “There are numerous mobile applications on smartphones … that make use of GNSS, together with the terrestrial network, to provide motorists real time traffic congestion information to direct these people to the most efficient, if not the most convenient, route towards their destination,” said the International Telecommunication Union (ITU).
LTE/5G
ITS can also leverage 3GPP-developed standards,
for example LTE and 5G, for data communication. This is especially the case with V2X or vehicle-to-everything, whereby the vehicle interacts with various objects in its surroundings. “3GPP has developed specifications to enable the use of LTE mobile networks to provide connectivity between vehicles, roadside infrastructure and pedestrians inside and around the connected vehicles,” ITU said. “3GPP is also looking at continuously evolving the V2X services in its coming releases including 5G. Future V2X releases will support, for example, enhanced safety use cases at high vehicle speeds, challenging road conditions with its improved reliability, extended range, lower latency, and enhanced non-line-of-sight (NLOS) capabilities.”
Others
According to Geospatial, other methods of communications include dedicated short-range communications (DSRC) using radio, and Continuous Air Interface Long and Medium Range (CAILM) using cellular connectivity and infra-red links.
Transmission equipment
To make transmission possible, various networking equipment is needed. These include traffic signal controllers, routers and network switches, among others. To operate in outdoor environments day in and day out and handle large amounts of data, the equipment must meet certain requirements as follows.
High capacity
The networking equipment must be able to process high volumes of data, especially at a time when
more and more network cameras are installed for vehicle counting and license plate recognition purposes. “Advanced ITS systems need higher bandwidth capacity in the 1–10 Gb/s range to be able to handle video applications. They must be very scalable and application-aware to be able to respond dynamically to rapidly shifting user demands during road incidents, congestion and other high use periods,” said Alcatel-Lucent in a post.
Power-over-Ethernet
The equipment must have Power-over-Ethernet features to support powered devices. “With the large number of sensors, cameras and other connected devices, power-over-Ethernet (PoE) will be compulsory on many access switches in order to reduce cabling requirements and simplify installation and maintenance,” Alcatel-Lucent said.
Roadside ready
The equipment must be robust enough for external operations 24-7 and meet other challenging conditions. “It will need to be both ruggedized and have built-in capacity to expand as new applications, sensors and devices are developed and installed. Spanning thousands of miles of highways and roads, access switches will also need to be linked by low-latency optical backbones to span the potentially long distances between nodes,” the post said.