June 17, 2003, 7:59 AM — A swath of radio frequencies recently approved by the U.S. Federal Communications Commission (FCC) as unlicensed spectrum has come into play in the growth of wireless broadband networks.
A 250MHz patch of the 24GHz band is now available unlicensed for point-to-point links between radios on towers or roofs with a clear line of sight between them. In addition to letting an enterprise or service provider span an environment where cables can't be laid, such as a creek, point-to-point wireless gives competitive carriers a way to quickly deliver high-speed data services without paying -- and waiting -- to use another carrier's lines, according to industry analysts. That could mean more options and lower bandwidth costs for many businesses.
Radio maker DragonWave Inc. said Monday it has added 24GHz capability to its AirPair-100 fixed wireless systems, which have been on the market since 2001 for use with licensed frequencies between 18GHz and 38GHz. AirPair is designed for use by both enterprises and service providers for access and backbone links, according to Erik Boch, chief technical officer and vice president of engineering at DragonWave, in Ottawa, Ontario.
AirPair can provide a link as fast as 100M bps (bits per second) that plugs directly into a Fast Ethernet port on a carrier's or enterprise's router, Boch said. With the new unlicensed-band capability, enterprises can save the cost and complexity of getting a radio license and carriers can quickly set up a link to a new customer or a new coverage area when the opportunity arises. This is especially good for competitive carriers that want to enter new markets quickly and without having to lease fiber capacity, Boch said.
"It allows you to sneak into the next guy's territory under the radar," Boch said.
The longest link created so far with AirPair is about 38 kilometers (24 miles), but some customers plan to deploy the technology over distances of more than 70 kilometers, he said. The strength of a signal isn't degraded over a long distance but very heavy rain over a long distance can cut it off, so DragonWave provides software with local rainfall information that helps customers in different locations find the right balance of distance and reliability, he added. Looking beyond its 100M bps technology, DragonWave is developing a system that would provide 1G bps of capacity, Boch said.
The radios are designed for easy installation and setup by employees who have never worked with radio equipment, Boch said. To position and test the radio units, the deployer can use a PalmOS PDA (personal digital assistant) with a DragonWave application, plugged into the PDA via its cradle port. The software tests the network connection and gives graphical instructions on how to position the antenna.