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Stealth wallpaper shields WLANs

Panels that block electronic eavesdropping on Wi-Fi traffic but allow radio and mobile phone signals to pass have been developed by BAE Systems

UK defence contractor BAE Systems has developed a stealth wallpaper to beat electronic eavesdropping on company Wi-Fi networks.

The company has produced panels using the technology to produce a screen that will prevent outsiders from listening in on companies' Wi-Fi traffic but let other radio and mobile phone traffic get through.

The FSS (Frequency Selective Surface) panels are made in the same way as printed circuit boards - layers of copper on Kapton polymer - and used on stealth bombers and fighter jets. They come in two varieties: passive, which is effectively permanent, and active, where various areas can be switched on and off to enlarge or limit the area of the network.

The panels are 50 to100 microns thick and can be applied to most surfaces including glass. A company spokesman claimed that they also helped reduce "noise" in buildings where a number of companies operate their own separate LANs.

BAE Systems developed the new material with £145,000 of funding from the Radiocommunications Agency, which is now part of Ofcom. BAE says the material is cheap and it will be developing it commercially through BAE's corporate venture subsidiary.

There is no timescale for its commercial availability.