This system provides a range of information about authorisations, licences and trades.
The UK frequency allocation table covers the radio spectrum allocations from 9KHz to 275 GHz.
The European Frequency Information system (EFIS) you can search for and compare spectrum utilisation across Europe. (external website)
Information on operational cellular radio transmitters in England, Scotland, Wales and Northern Ireland.
Ofcom is required to exempt radio stations, equipment or apparatus from the need to hold a wireless telegraphy licence where their use is not likely to involve any undue interference to other legitimate use of radio spectrum.
The Ministry of Defence conduct occasional tests on military systems which may result in some loss of service to civilian users of the Global Positioning System (GPS).