Radar‑Based Detection, Cataloging, and Tracking of Objects in Orbit.

Orbital security as a central mission

Communication, navigation, and Earth observation underpin modern society — and all of them rely on dependable satellites. At the same time, the number of objects in orbit and the associated collision risks continue to grow. Radar‑based space surveillance provides the necessary transparency: it detects, tracks, and catalogs satellites, rocket bodies, and fragments independently of light and weather conditions. Fraunhofer FHR combines scientific excellence with operational experience to achieve this. Our ambition: reliable situational awareness with quantified uncertainties — fully compatible with the EU‑SST program of ESA (Space Surveillance and Tracking) and directly usable for maneuver planning and risk analysis. These capabilities strengthen modern space surveillance and robust space situational awareness.

TIRA and GESTRA: complementary sensor systems

Two systems form the core of our sensor suite: the Tracking and Imaging Radar TIRA provides highly sensitive range, Doppler, and angle measurements and — when required — high‑resolution radar imaging. GESTRA, a fully digital phased array, is designed for persistent space surveillance, high throughput, and automated track generation. Together, they cover the full spectrum from wide‑area detection to precise orbit tracking and verification through imaging. Precise time and frequency references, adaptive waveforms, and interferometric techniques increase range, sensitivity, and angular accuracy — even during short visibility windows and at low SNRs (signal‑to‑noise ratios). These technologies support advanced radar tracking and resilient phased‑array sensing.

From measurement to precise orbit prediction

The acquired measurement data are processed in powerful evaluation chains. Through precise orbit reconstruction, consistent orbit models with quantified uncertainties are generated. By linking TIRA measurement data with the design principles of GESTRA, object catalogs can be created and reliable predictions computed. Result‑based methods also support the early detection of changes in orbit, contributing to robust orbit determination and conjunction analysis.

Operation, validation, and further development

Measurement campaigns and continuous operation provide essential contributions to the advancement of these technologies. GESTRA demonstrates automated catalog maintenance under real conditions, while TIRA serves as a reference system for reconnaissance and validation tasks. Studies on distributed, bi‑/multistatic architectures show how coverage and resilience increase through networked systems — a key building block for future European observation constellations. In parallel, we investigate new system concepts such as networked radar architectures to further improve coverage and robustness.

Your benefit: reliable data for safe missions

The technologies developed at Fraunhofer FHR support space agencies, authorities, and industry in mission planning, mission execution, and risk assessment in orbit. Our service portfolio ranges from measurement campaigns and system studies to integration into existing infrastructures — providing dependable data for secure and efficient space operations.