The THAUMAS initiative (Tailored and Harmonised satcom for ATM Uses, Maximising re-use of Aero SwiftBroadband) has been defined in line with the Artes 10 objectives. Starting from the well proven SwiftBroadband technology, the project will define and validate the upgrades needed to offer ATM services. The resulting system, called SB-S (SwiftBroadband-Safety) will be designed for compliance with stringent services and applications defined in the frame of the SESAR programme.
The THAUMAS project has been defined with the following key objectives:
- To derive a satellite communications solution that complies with the stringent ATM expectations identified in the frame of the SESAR programme,
- To build on Inmarsat’s heritage in the provision of aeronautical safety services,
- To take advantage of the powerful and spectrally-efficient Inmarsat-4 and Alphasat satellites to enable low-cost avionics and service charges.
Inmarsat was the first civil operator to introduce satellite communications services for the aeronautical industry, with the launch of its first aeronautical service in the early 1990s. Today, more than 10,000 aircraft in the air transport, business aviation and government sectors rely on its in-flight voice and data connectivity Inmarsat is currently the principal satellite operator providing global aeronautical safety services that comply with the safety requirements of the International Civil Aviation Organisation.
Inmarsat's latest generation aeronautical system, SwiftBroadband, which was developed in cooperation with ESA, offers the potential to support both Oceanic Safety services, and with further modification to satisfy the performance requirements demanded in Continental Airspace. Within Iris, the THAUMAS team will research modifications to the system in order to meet the more stringent latency and reliability requirements, and to enable new, smaller, low-cost avionics.
As a result THAUMAS will define and start the validation of the upgrades to SwiftBroadband required to achieve Continental Safety Services as a complement to the future terrestrial ATM services being developed by the SESAR programme. In particular, system design activities will be based on concept of operation known as dual-link (satcom and terrestrial L-DACS), where datalink messages are sent via both paths to increase reliability and availability.
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From a technical point of view, the key challenges are in capabilities to transmit short, bursty messages with low latency, and to consider new aircrafts equipment compatible with a wider range of aircraft (SwiftBroadband is mainly used on large aircrafts).
Another critical aspect is to define and develop (when required) the verification and validation means that are needed to ensure the compliance with the end users expectations or ATM services requirements.
All those activities should in the end allow to confirm that the proposed design complies with technical, safety and security requirements.
The overall objective of the Artes10 initiative is to define a satcom solution, compatible with aeronautical needs. The THAUMAS consortium has been defined around key actors (satellite operator and manufacturer, and aeronautical communication service provider), with the objective to reach a solution acceptable by all parties, as well as compliant with SESAR requirements. In particular, the interest of the THAUMAS project will be to reduce the cost of the final solution.
In addition, it is expected that this approach will simplify the transition phase between today and the 2020+ context.
The THAUMAS system architecture is widely based around the existing SwiftBroadband (SB) system. SB supports the full set of BGAN services, with standard IP data rates up to 432kbit/s through the standard-fit Aero-H and Aero-I antennas. Swiftbroadband already incorporates techniques to maintain link connectivity in challenging propagation environments encountered over oceans and at high latitudes.
The SB-S system defined within THAUMAS should be part of the dual-link architecture proposed within SESAR to support new applications (for instance 4D trajectory).
A previous phase of THAUMAS has established the need for further improvement to support ATM services:
- Compatibility with Low Gain Antenna (suitable for a wider range of aircraft types), by introducing new channel modulation and coding rates,
- Mechanisms to efficiently support message traffic characterised by short latency and bursty data traffic,
- Fast recovery mechanisms to ensure continuity of service in the event of planned maintenance site switches, sub-system failure, etc.,
- Support of decentralised ground segment architectures and seamless handover of aircraft from one Functional Airspace Block to the next.
Those topics will be the core technical activities during the current phase 1.
The THAUMAS project has completed the steps of clarifying the requirements to be met, and defining the modifications required to reach the compliance to those expectations.
The current phase 1 of the project will deeper investigate the way to implement the modifications required. Those design activities will be done in close loop with safety and dependability’s analysis. It will also start the validation of the proposed options, using both test bed and simulations tools to assess performance under high traffic load, and fallback modes.
Phase 1 was started on the 4th of July.