EISCAT_3D is a new advanced radar system for research into incoherent scattering, currently being built by EISCAT.
EISCAT_3D is a new advanced radar system for research into incoherent scattering, currently being built by EISCAT. The technology itself is not new, but the design and capacity of the new system in this form is new to the research community.
Technical innovations are often met with questions and concerns. We try to answer the most frequently asked questions here.
EISCAT_3D is an advanced radar system designed for scientific studies of the Earth’s atmosphere, ionosphere and near-Earth space. It uses a technique known as Incoherent Scatter Radar (ISR) to measure fundamental physical properties of the upper atmosphere, such as plasma density, temperature and motion.
EISCAT_3D enables research into phenomena including the aurora borealis (Northern Lights), space weather, space debris, atmospheric dynamics and long-term changes in the near-Earth environment.
The “3D” refers to EISCAT_3D’s ability to make true three-dimensional measurements. By combining observations from multiple radar stations in Norway, Sweden and Finland, the system can determine not only where something happens, but also how it evolves in space and time.
This provides scientists with a much more complete picture of physical processes in the upper atmosphere than was previously possible.
An incoherent scatter radar transmits radio waves that are scattered by free electrons in the ionosphere. By analysing the very weak signals that return to the radar, scientists can determine key plasma parameters with high accuracy.
This technique has been used successfully by EISCAT for more than 40 years, and EISCAT_3D represents the next major step in its development.
A phased array antenna consists of a large number of simple antennas that work together as one powerful, steerable system. In EISCAT_3D, signals from thousands of antennas are combined electronically, allowing the radar beam to be redirected in milliseconds without moving any physical parts.
This makes it possible to observe many different regions of the sky almost simultaneously.
The core radar array consists of roughly 10,000 antennas covering an area about 70 metres in diameter. The core site near Skibotn, Norway, also includes smaller auxiliary arrays used for calibration and specialised measurements.
The radars in Kaiseniemi, Sweden and Karesuvanto, Finland consist of about 5000 antennas each. And are about half the size of the core site in Skibotn.
EISCAT_3D uses a distributed solid-state transmitter. Each active antenna element has its own amplifier, delivering up to 1,000 watts of peak power.
In the first construction stage, approximately 5,000 antennas at the core site will be equipped with transmitters, providing a total peak power of around 5 megawatts.
The radar signal is scattered by individual electrons in the ionosphere, which are extremely small. Only a tiny fraction of the transmitted energy returns to the receivers, so high transmitter power, large antenna arrays and very sensitive receivers are required to obtain usable measurements.
EISCAT_3D is powered by the national electricity grids in each host country. At the core site in Skibotn, a hydroelectric power plant is located nearby. Uninterruptible power supply (UPS) systems protect critical equipment in the event of power interruptions.
Yes. EISCAT_3D is designed to fully comply with international and national safety standards for radio frequency exposure.
Radio wave levels outside the fenced areas are well below permitted limits. The system is interlocked so that transmissions automatically stop if authorised personnel enter restricted zones. Regular safety inspections are carried out by authorities and by EISCAT itself.
The environmental impact of EISCAT_3D is very limited. The system does not produce emissions, waste or noise during normal operation. The sites are carefully selected and designed to minimise disturbance to the surrounding landscape and wildlife.
Summary plots and visualisations from many experiments will be available online. Researchers who wish to conduct their own experiments must either be a member of the EISCAT or apply through a peer-reviewed proposal process.
All research conducted with EISCAT_3D is open and civilian; no defence-related activities are permitted.
EISCAT_3D is operated by EISCAT AB, an international research organisation with more than four decades of experience in operating incoherent scatter radars.
EISCAT is funded by its member countries and affiliated institutes. The EISCAT currently includes Finland, Japan, Norway, Sweden and the United Kingdom, with additional affiliated partners worldwide. Development and construction have also been supported by the European Union.
The first stage of EISCAT_3D includes three sites:
Future stages will add additional sites to expand coverage and capabilities.
The sites form an optimal geometric configuration for three-dimensional radar measurements. They are also located beneath the auroral zone, where interactions between the solar wind and the Earth’s atmosphere are particularly strong.
The relatively clear skies in the region also allow radar data to be combined with optical observations, such as auroral imaging.
Yes. EISCAT_3D plays an important role in space weather research by measuring how solar activity affects the Earth’s upper atmosphere. These observations improve our understanding of processes that can disrupt satellites, navigation systems and radio communications.
While EISCAT_3D is primarily a research instrument, its data also support the development of future space weather monitoring and forecasting tools.
The system can detect space debris and micro-meteors, and these observations are part of the scientific programme. Aircraft and satellites reflections are minimised by the location of the transmitter site and by data processing techniques, as such reflections can interfere with atmospheric measurements.
Results from EISCAT_3D are published in peer-reviewed scientific journals and presented at international conferences. While the large raw data sets are archived by EISCAT, the scientific findings are openly available to the global research community and the public.
EISCAT_3D is designed for long-term, year-round operation over several decades. Its modular design allows the system to be upgraded and expanded as technology and scientific needs evolve.EISCAT_3D.