Projects

The threat posed by landmines on the ground is increasing in light of wars and conflicts worldwide. In efforts to clear landscapes of mines, finding explosive devices in the soil poses an enormous challenge: a large share of objects are empty oil cans, broken shopping carts, or simply an old tin. There are also cases where, when placing improvised explosive devices, scrap is laid out to hinder the enemy from locating them. This is where the work of the researchers led by Dr. Christian Bräu, group leader UWB radar at Fraunhofer FHR in Wachtberg, comes in.

Die Zukunft der Weltraumbeobachtung liegt in multistatischen Radar-Systemen – und das Fraunhofer FHR ist der Partner, um diese Schlüsseltechnologie zu nutzen. Mit dem weltweit führenden Tracking and Imaging Radar TIRA bietet das Institut bereits heute eine einzigartige Infrastruktur, die durch strategische Kooperationen kontinuierlich erweitert wird.

In Wachtberg, near Bonn, the Fraunhofer FHR operates the TIRA (Tracking and Imaging Radar) large-scale radar facility on behalf of the Federal Ministry of Defense and the Federal Republic of Germany as an experimental sensor for space surveillance. With its comprehensive capabilities for radar-based space situational awareness, TIRA makes an important contribution to the protection of national infrastructure in space. TIRA also provides mission support for international space agencies and satellite operators.

You know it from driving: when you pass an object, you only get a relatively fleeting glimpse. If you circle around the object, you can view it from all sides. The same applies to radar imaging. Typically, SAR is flown with an aircraft in a straight line over the object and radar data are collected during that pass. With circular SAR, the aircraft flies circular orbits over the area to be observed. While this makes signal processing more challenging, it provides a significantly expanded data base because a given area can be illuminated over a long period — and as with radar, independent of time of day and weather.

More than 2,700 inactive satellites, over 54,000 debris objects larger than 10 cm, and 1.2 million fragments between 1 and 10 cm: the growing volume of space debris poses a severe threat to space infrastructure. Collisions and further fragmentation endanger operational satellites and, with them, critical services in communication, navigation, and Earth observation. Within the STRATOLASER project, Fraunhofer FHR—working as part of a consortium—is investigating a novel approach to removing space debris. The objective is to develop a demonstrator of a laser ablation system mounted on a stratospheric balloon.

The field‑of‑view range of phased array antennas is inherently limited by physical constraints. Through the use of electronically tunable metamaterials, this range could be expanded in the long term, thereby enabling new application possibilities

Radar is the most important sensor for autonomous driving. A hHigh spatial resolution is achieved, according to the multiple-input/multiple-output (MIMO) principle, by a large number of antennas, each connected to individual gates ports of integrated radar ICs. When designing the complex high-frequency interconnect networks, the previously used printed circuit board technologies reach their limits.

Future-proof space situational awareness with radar: Fraunhofer FHR has further developed the signal processing systems of the target-tracking radar at the TIRA large-scale radar facility, thereby significantly expanding the capabilities of radar-based space observation. A special target was chosen for the first experiments with the new instrument: the Moon. The result is a high-resolution radar image of the entire lunar surface visible from Earth.

TIRA-Digital modernizes the signal processing of the L-band target-tracking radar of the space surveillance radar TIRA. Through an innovative, software-based architecture, radar signals are digitized directly at the antenna and processed in real time. The obtained data underpin forecasts, warnings, and analyses for national and European space infrastructure and strengthen Germany’s sovereignty in space intelligence. Thus, TIRA Digital creates a future-proof foundation for reliable decision-making and the safe operation of orbital systems.

Fraunhofer FHR is equipped with a variety of instruments and facilities to perform numerous types of RF measurements. This includes the characterization of antennas and RF circuits, monostatic radar cross section (RCS), and measurements of electromagnetic material parameters. In addition to standard procedures, customized measurement solutions can also be developed. Our in-house precision mechanics workshops provide valuable support.