New ESA project to explore advanced off-air functional and performance testing of different BGAN aero terminals and aero L-band antenna types taking realistic link impairments into account. The project, titled ‘Flight Path Emulator (FPE)’, is set to be carried out from Q1 2023 to Q2 2024 and will entail development of a test system used to emulate Inmarsat BGAN satellite data communication, ground station and core network during flights.
On-air Testing: Expensive and Insufficient
On-air testing of BGAN aero terminals is an integral part of development, but it has its obvious challenges and limitations. Not only is it expensive, but on-air testing also limits the available testing scenarios and the repeatability of certain scenarios.
The Flight Path Emulator project aims to simplify as much as possible the creation and execution of a highly complex, realistic and reproducible connectivity test, where only a relatively simple flight path and antenna characteristics serve as input.
Use Cases
The FPE will address the following use cases:
- As a SwiftBroadband-Safety terminal manufacturer I want to test my terminal under realistic conditions in a reproducible off-air setup so that I can validate its operation and performance. Realistic conditions include different connection handovers and typical channel impairments.
- As a system integrator I want to test my terminal using different aircraft antenna configurations so that I can validate its operation and performance. An aircraft trajectory input shall emulate aircraft banking and tail blocking and thus result in realistic satellite data link impairments.
- As an application developer I want the ability to make reproducible tests in an off-air emulated realistic environment so that I can verify operation and performance of my flight management system. Realistic connectivity conditions include bandwidth limitations, delays etc. caused by the position and behaviour of the aircraft.
System Architecture and Features
To achieve the goal of a realistic yet simplified method of testing, the architecture is intended to support emulation of the BGAN radio frequency (RF) interface by emulating the physical layer and the entire BGAN Radio Access Network and Core Network. This transforms on-air testing into on-bench testing using a digital twin. The emulation is implemented using a physical layer tester and BGAN network emulator that implement the protocol layers and support an interface allowing data exchange to an IP network interface.
The FPE is configured with a given antenna model incorporating the antenna characteristics and a given antenna placement on the aircraft in the test system. Test inputs in the form of an aircraft trajectory result in a dynamic RF link along the flight path and associated signalling with the BGAN network. In addition, different link impairments are automatically and realistically introduced by the FPE as a result of aircraft banking and other manoeuvring. Thus, the connection QoS and network signalling are realistically emulated from a recorded or designed flight path.
Benefits
The digital twin testing environment enabled by the Flight Path Emulator will provide the following benefits:
- Emulate BGAN functionality in a controlled test environment.
- Emulate typical satcom link impairments.
- Reduce significantly the number of test flights required to test terminals, installations and applications.
- Avoid exposure on the live network.
- Avoid paying for satcom airtime when testing.
- Automate, reproduce and document complex test scenarios.
- Test end-to-end exchange of any type of user data.
You can follow the project on the official ESA project page HERE.
