5GHz ratification will open point-to-point floodgates

Point-to-point wireless links will get a big boost in December, when The Radiocommunications Agency (RA) is expected to approve the use of the 5GHz spectrum. The incumbent spectrum user of the contentious Band C, the U.K. Ministry of Defence, has been placated by a “soft licence” system, but the price of a few pounds a year will not deter users, say sources close to the process. 802.11a wireless LANs, which also use the 5GHz band will also get a boost, although, they are not expected to take off any time soon.

“At the last meeting, the RA suggested that Band C could be ratified during December,” said Paul Munnery, technical director of Wireless CNP, “I would expect that to be nearer the end of December. But the bones of the standard have been thoroughly thought out and we will see ratification.”

The Ministry of Defence has resisted opening up the spectrum, because it has radar systems operating in Band C of the 5GHz part of the spectrum. However, the frequency is used by the 802.11a wireless LAN – still scarcely present in Europe – and supports Orthogonal FDM (OFDM) signalling which is ideal for longer-distance point-to-point links used for community broadband and linking branch offices.

“This spectrum will open up a new world of possibilities for us,” said Munnery. “The OFDM radio it enables will let us connect locations, even where there is no clear line of sight.” Wireless CNP is preparing for its new freedom in the U.K., with an expanded staff of engineers, having already deployed OFDM in Ireland and continental Europe, where it is free for use.

Users have been concerned that terms of the so-called “soft licence” would be too onerous, under MoD pressure, but they will in fact be easy to meet, said Munnery. “Wireless CMP will be super licence holder,” said Munnery: “We can deal with the licence application, for many users. Others will simply register on a web site.”

Registration will require the user to give map references for the network – to make sure it does not overlap with MoD-defined exclusion zones, and pay a nominal fee. Users have been concerned that this fee might be set too high, but Munnery believes it will be “tiny, compared with the EU$50 (US$51) a month required of any current users.” Other sources suggested the Band C registration fee could even be as low as EU$1.

Equipment for these links must have dynamic frequency selection so it can say “excuse me” and change frequency if it detects a radar sweep, and automatic power control, so transmitters only emit enough power to reach the receiver.

Meanwhile, 802.11a, operating under a 100mW power ceiling, is not subject to such strong regulations. No one in the U.K. is operating a public 802.11a hotspot (tell us if you know different) according to Warren Lewis, a spokesman for Buffalo Technology Inc., partly because it requires a licence. However “a lot of people are doing it because nobody is being caught,” he went on.

Despite the slow start, Lewis reckons .11a is the future: “a is going to be fantastic,” he said. “It will wipe out b and g. But it is still 12 months from serious use in the U.K.” He believes the RA has acceded to demands to free the band up partly because the arrival of dual band a/b/g access points and NIC cards has made it impossible to police: “The government has no choice but to pull it all away.”