Ofcom has recommended that the European version of Ultra-wideband (UWB) should require additional anti-interference technology to prevent problems with wireless broadband systems.

The communications watchdog issued its recommendation to the European Conference of Postal and Telecoms Administrators (CEPT) yesterday, following a lengthy consultation period. CEPT is in the process of harmonising UWB plans across the European Union in order to create a single unified market for the technology.

UWB is a short-range, high-speed wireless standard designed for connecting devices such as PCs, storage and printers, or consumer electronics systems such as DVD players, televisions and speakers. The problem is that devices using the already existing UWB standard from the United States could interfere with the Broadband Fixed Wireless Access (BFWA) systems now appearing on the scene, rendering Internet connections next to useless.

"The US has already developed a specification for UWB. However, Ofcom believes that this does not provide adequate protection against interference with other wireless devices in Europe because of the different uses of radio spectrum in the US and Europe," Ofcom said in a statement.

The solution is for UWB systems in the 3.1 to 4.2GHz bands to be fitted with "detect and avoid" systems, which search for nearby broadband wireless signals and switch frequency to prevent interference, Ofcom said. Devices can do without such anti-interference systems only if they are transmitting below a power level of -85dBm/MHz, Ofcom said.

The recommendation follows lobbying by the WiMax Forum, the industry consortium pushing WiMax, the most hyped BFWA standard. In March, the WiMax Forum presented Ofcom with a consultation document [pdf] arguing in favour of requiring anti-interference technology in UWB devices.

"The need for mitigation to protect licenced operation of WiMax type services has already been established," the Forum's document said. "Such mitigations should be mandatory to ensure harmful interference is avoided, but should be 'technology neutral' to ensure that all potential UWB technologies can comply."

Among Ofcom's other anti-interference recommendations were for UWB transmitters to use Transmit Power Control technology for situations when a number of other UWB devices are nearby, and for the introduction of a minimum Pulse Repetition Frequency.

In recent months Ofcom has outlined a broad plan to deregulate wireless spectrum in the UK, but has said it would continue regulating where needed to make sure different technologies could work together.

Ofcom's full recommendation to CEPT is available from Ofcom's website [pdf].