HLA-Based Simulation for Federated Satellite Systems
Published:
Role: Thesis supervision · Chair of Spacecraft Systems, Technical University of Munich
In a Federated Satellite System (FSS), satellites belonging to different missions and operators trade resources in a market-based network to pursue a shared goal. Testing that idea properly needs a simulator in which a satellite’s communication capability is tied to its actual operational state - power, attitude, pointing - rather than assumed.
This project built that simulator on the IEEE 1516 High Level Architecture standard, using the open-source CERTI run-time infrastructure so that multiple simulators, FlatSats and digital twins can co-simulate one scenario in a synchronised way. Each satellite subsystem (ADCS, EPS, TMTC) is a C++ class with its own propagation, and the architecture was extended to Hardware-In-the-Loop through a radio module on a Raspberry Pi.
A 100 CubeSat federation was then analysed as a directed, SNR-weighted network:
- Goodput per link, time-averaged across a 24-hour window under different operational hypotheses.
- Time To Spread (TTS) - how long a single message takes to reach every node - which behaves much like an epidemic curve, with an exponential start and a long tail of poorly connected satellites. Message multiseeding and a spreading cutoff cut the average TTS from 5.3 to about 3.4 hours.
- Katz dynamic centrality as a cheap predictor of TTS, avoiding a computationally expensive Monte Carlo sweep.
The network was then tested against a real time-critical scenario: the Copernicus Emergency Management Service rapid-mapping request for the Emilia-Romagna floods of May 2023, with satellites bidding for the imaging task using an onboard reward function balancing sun elevation, cloud cover, battery state and slew cost.
The headline finding is that tying inter-satellite links to real operational constraints degrades network communicability well below what the literature assumes - but not so far as to invalidate the FSS paradigm for disaster response.
Related publication: Advancing Satellite Network Performance: Network Analysis for Federated Satellite Systems, IEEE Access, 2024.