Radio engineers need to keep a close eye on the UK's changing skyline, a seminar heard last week.

The rising number of wind farms and their increasing potential to affect air traffic control radars and other radiocommunications infrastructure was the central theme of the event run by radio planning and modelling company ATDI in London on Thursday, July 10.

There are currently 176 wind farms in the country and permission has been granted for a further 136 with another 226 now at the planning stage. ATDI lead engineer Paul Grant says: "This phenomenon is growing at an amazing rate and radio engineers need to be ever more vigilant about the potential impact on signal quality, on radars and communications links. We can't just let this creep up on us."

Grant gave one of the key addresses at the seminar along with ATDI director Cyprien de Cosson and David Bacon, db Spectrum Ltd. The seminar was attended by delegates representing a broad range of civil and military radio users.

Delegates were shown pictorial analyses of the possible problems the growth in the number of wind farms may cause and the strategies for addressing these difficulties.

The seminar considered the wind turbine and collectively, wind farms, as sources of reflected energy. Reflections both reinforce and cancel wanted signals received. Current methods of protection including Fresnel zone clearance techniques between microwave links and wind turbines were debated along with the proposals contained in Ofcom's fixed-link exclusion-zone paper.

For further information, contact Sarah Sasson, ATDI Ltd, +44 (0)1293 522052 or by sarah.sasson@atdi.co.uk.