The Need to Protect “Our” Radio Frequencies
We often take for granted the seamless operation of our meteorological infrastructure: when, as national meteorological institutes, we launch radiosondes, these devices communicate via radio links to our ground stations; our precipitation radars scan the atmosphere for rainfall and hazardous weather phenomena; and our meteorological satellites observe the globe, transmitting their data via radio links and ground stations to our meteorologists. For a long time, we had every reason to do so. However, since 2003, this situation has changed dramatically.
At the World Radiocommunication Conference in 2023, a decision was made to authorise RLAN equipment (such as Wi-Fi) to use, under specific conditions, the same frequencies as our C-band radars—the most widely used type of precipitation radar in Europe. In theory, this should have been manageable, but in practice, much of the equipment that entered the market did not comply with these specific conditions. As a result, since 2006, interference with our C-band radars has become a serious and persistent problem.
As a meteorological community, we have learnt that protecting the radio frequencies which enable us to inform the public and professional partners—such as the aviation sector—about dangerous weather conditions must be a top priority. At the European level, EUMETSAT and EUMETNET have initiated programmes to safeguard radio frequencies, and the WMO has established an expert team on frequency management.
During the most recent World Radiocommunication Conference (2023), we, as the meteorological community, were well prepared and succeeded in safeguarding the frequencies essential to our work. However, technological development is advancing rapidly, and new threats are emerging on the horizon.
Some examples include:
– A new type of C-band radar (using solid-state transmitters) may be even more susceptible to interference from RLAN equipment. Further research is needed, and additional restrictions on such equipment may be required.
– The introduction of new security scanners could cause further interference with our radars in both the X and C bands.
– Detect and Avoid Systems on unmanned aerial vehicles (UAVs) may jeopardise the operation of our C-band radars.
– The mobile industry poses a broad threat to all frequencies we use, both through remote sensing from the ground and from space.
Through the efforts of the WMO, EUMETSAT, EUMETNET (via the EUMETFreq programme), and our national radio frequency authorities, we strive to inform and influence decision-makers, and to prepare ourselves for the next World Radiocommunication Conference in 2027.
