Air Traffic Service

Description

Air Traffic Service (ATS) in 3GPP refers to the standardization of cellular network capabilities to support communications for air traffic management (ATM). This encompasses the exchange of critical information between aircraft (aerial user equipment, AUE), ground-based air traffic control (ATC) units, and other aviation stakeholders. The service is designed to meet the stringent requirements of aviation safety and regularity, including high reliability, low latency, security, and availability, over a wide geographic area that includes airspace and ground stations.

The architecture for ATS leverages existing 5G system components but introduces specific enhancements and new functional elements to meet aviation needs. Key architectural aspects include support for aerial user equipment (AUE), which are aircraft-mounted devices connecting to the 5G network. The network must support mobility at high speeds and altitudes, requiring enhancements to mobility management and radio resource control. Ground-based network functions, such as the Access and Mobility Management Function (AMF) and Session Management Function (SMF), are extended with aviation-specific policies and service requirements. Furthermore, the architecture considers interconnection with existing aeronautical communication networks, such as those based on ATN/IPS or other legacy systems, through defined network exposure functions and interworking units.

ATS operates by establishing dedicated communication services between AUEs and ground ATC units or airline operational control (AOC) centers. These services can include voice communications (controller-pilot data link communications, CPDLC) and data services for surveillance (e.g., Automatic Dependent Surveillance–Broadcast, ADS-B) or flight information. The 5G network provides the underlying connectivity with quality of service (QoS) flows tailored to aviation profiles, ensuring prioritized handling of safety-related messages. Security is paramount, with mechanisms for mutual authentication between AUE and network, integrity protection, and confidentiality, often aligning with aviation-specific security frameworks.

The role of ATS in the network is to transform 5G into a viable complement or eventual successor to traditional aeronautical dedicated spectrum systems (like VHF datalink or satellite links). It enables more efficient use of spectrum, higher data rates, and integration with broader mobile ecosystem innovations. For network operators, it opens a new vertical market requiring specific network slicing, edge computing, and service management capabilities to deliver certified, reliable services to the aviation industry.

Purpose & Motivation

ATS was created to address the growing need for modernized, scalable, and cost-effective communication solutions for air traffic management. Traditional aeronautical communication systems, such as VHF voice and datalinks, are facing spectrum congestion, limited data capacity, and high operational costs. Furthermore, the anticipated growth in air traffic, including drones and advanced air mobility (AAM) vehicles, demands a more flexible and data-rich communication infrastructure. 3GPP-based cellular networks offer a globally deployed, continuously evolving technology base that can provide high bandwidth, low latency, and robust security, making them a compelling candidate for supporting both existing and future ATM communications.

The motivation for standardizing ATS within 3GPP, starting in Release 17, stems from collaboration between the telecommunications and aviation industries. Bodies like the International Civil Aviation Organization (ICAO) and aviation authorities have been exploring the use of commercial mobile networks for safety and regularity of flight communications. 3GPP standardization ensures interoperability, global roaming for aircraft, and economies of scale by leveraging the massive deployment of 5G networks. It aims to define the technical enablers that allow mobile network operators to offer services that meet the rigorous regulatory and performance requirements of aviation, thereby facilitating the convergence of terrestrial mobile and aeronautical communications.

Previous approaches relied on isolated, specialized systems for aviation, which led to fragmentation and slower innovation cycles. By integrating ATM requirements into the 5G framework, ATS addresses limitations in spectrum efficiency, data service capabilities, and network densification. It enables new operational concepts, such as seamless connectivity from ground to cruise altitudes, support for dense urban air mobility operations, and integration with air traffic management digitalization efforts like System Wide Information Management (SWIM).

Key Features

• Support for Aerial User Equipment (AUE) with high-altitude and high-speed mobility
• Aviation-specific Quality of Service (QoS) profiles for safety-critical communications
• Enhanced security mechanisms meeting aeronautical certification requirements
• Interworking with legacy aeronautical networks (e.g., ATN/IPS)
• Network slicing for dedicated Air Traffic Service instances
• Support for Controller-Pilot Data Link Communications (CPDLC) and surveillance data services

Evolution Across Releases

Defining Specifications