ETRI WEBZINE

The lack of a common communication standard among drone makers has made it difficult for information to be shared between drones, but a Korean research team has found a solution.
Electronics and Telecommunications Research Institute(ETRI) announced that four contributions related to the “Unmanned Aircraft Area Network(UAAN)” were established as international standards at the International Organization for Standardization(ISO^*) meeting in Vienna, Austria on March 22.
The technology used by the research team in the international standard is a drone distributed communication technology that prevents the risk of collision between drones when flying drones(unmanned aircraft) and supports the simultaneous operation of hundreds of drones.

* ISO/IEC JTC1/SC6(communication and information exchange between systems)

The international standards that established at this Austria meeting are standards for unmanned aircraft area network(UAAN), and covers four detailed technologies: ▲unmanned aircraft communication model and requirements ▲shared communication ▲control communication ▲video communication.
As ETRI researchers’ drone distributed communication technology has been establiched as an international standard, the market outlook is also bright as many of the developed technologies become international standard patents.
The key technology of this international drone communication standards is 『Evolved Wireless Ad-hoc Network(EVAN)^*』 technology. EVAN technology, as a hyper-connected original technology that will lead the future society, was applied to the development of the international standards for this ‘unmanned aircraft area network’ and has been recognized as a good solution by standards experts worldwide.
With the application of EVAN technology in the drone field, it became possible to share information between drones, prevent collisions between large-scale drones, and prevent collisions with ground movement obstacles based on it. The communication distance for a recognition service in this standard is about 5km, and it allows drones recognize each other as well as helicopters, thereby securing flight safety of manned and unmanned aircraft at the same time.
For example, it was difficult for drones from different manufacturers to fly to spray pesticides on large farmland simultaneously, or for several drones to fly over the fire area simultaneously in the event of a large fire, but this technology solved these problems.

* Evolved wireless ad hoc network: Unlike LTE, which requires a base station, a modern communication network that uses an auxiliary channel that serves as a base station instead of having a base station

In particular, the research team explained that compared to the heavy and expensive drone recognition radar, the communication modem of the ‘UA area network’ standard can be manufactured lightly and inexpensively in the tens of thousands of won, making it very suitable for drone recognition service.
In addition, ETRI explained that this standard technology enables interconnection of drones as well as related devices. In other words, drone-related services such as drone control and drone image transmission, mutual recognition between drones, autonomous collision avoidance, illegal drone detection, mobile obstacle recognition, and communication with takeoff and landing sites can be provided as one integrated communication platform.
Through this, Korea will be the only country in the world capable of autonomous collision avoidance between drones by utilizing the international standard for ‘Unmanned Aircraft Area Network’ and the ‘Low Altitude UA Detection and Avoidance Application Layer Technology’ standard of the Korea Telecommunications Technology Association(TTA).
Also, if the communication modem of this standard is installed on a moving obstacle that is not displayed on the 3D map, it is of great help in autonomous drone flight. In addition, it supports services such as direct communication with vertiport which is a drone taxi take-off and landing site, and a flight priority(dynamic geofencing) service when maintaining bridges or surveying buildings, and if applied to defense drones, it can overcome North Korea’s radio interference.

ETRI researchers explained that in this standard, since the drone transmits a password(trust field^*) that changes in each signal transmission, it is possible to automatically determine whether the drone is a legitimate drone or an illegal drone from the ground.
Furthermore, ETRI researchers announce that ETRI’s ‘Unmanned Aircraft Area Network’ standard can be utilized for PAV(Personal Air Vehicle) communication, such as drone taxis. Disconnection of the mobile communication network is fairly common in the airspace, unlike on the ground, and this standard is particularly ideal as a communication standard to supplement this. Internationally, another redundancy communication is an essential requirement for Urban Air Mobility(UAM^**).
Lim Chae-deok, head of the Air Mobility Research Division at ETRI, said, “The establishment of this international standard will secure drone operation safety, which is essential for servicing commercial drones. This standard adopted the EVAN technology, which is the only technology in the world that has low cost and high performance compared to Wi-Fi and mobile communication such as LTE, so it will be of great help in leading a fast and convenient hyper-connected society in the future.”
According to ETRI researchers, EVAN technology will be expanded to a single communication platform that will provide a variety of services such as the control of home devices/appliances/vehicle, indoor navigation, smartphone kiosk connection, children’s safety around school, illegal vehicle arrest, and search for missing persons.
This international standardization work was carried out as a part of the standard technology improvement project of the Ministry of Trade, Industry, and with the participation of the Korea Drone Industry Promotion Association, led by ETRI, which is the host organization. In March 2020, Hyungu Hwang, principal researcher at ETRI, and Kang Shin-gak, head of the Standards Research Division, took over as editors, and standardization work began, with results coming four years later.

* Trust field: Password that changes every 2ms slot. Similar to banking OTP technology. Valid only in the slot that receives the packet.
** Urban Air Mobility(UAM): A futuristic metropolitan public transit system that makes use of the sky as a passageway.