Fixed Wireless Equipment

The 1 Gbps Full Duplex Radio

These radios aren't new, but it took us some time to believe they were real.

by Alex Goldman ISP-Planet Managing Editor [September 20, 2007]

We contacted the company to find out how they get that kind of performance over real distance (1 to 5 miles) and learned something about spectrum ranges that many WISPs may not know exist.

At Spring ISPCON, I asked Tom DeReggi if there was anything I should look into, new technology or products of interest. Always polite and kind, he suggested I look into Santa Clara, Calif.-based BridgeWave.

When I told him, last week, that I was finally ready to talk to the company he admitted that he's been using cheaper Proxim gear that offers the same gigabit speed but at half the range and with a less sophisticated product. Proxim's got better prices, he said, and added, "Bridgewave still has the finest piece of gigabit hardware on the planet. I really respect what they have done from a technical perspective. They are the gigabit authority in my book."

So I was interested in learning more.

I attended a webinar and then later scheduled an interview. The webinar covered the technology in general and presented the case study of Lexington, Ky.-based WISP QX.net, an ISP that evolved from residential dialup to business wireless. It was sponsored by TESSCO, the wireless equipment distributor.

QX.net uses a combination of BridgeWave gear, which operates in 60 GHz and 80 GHz spectrum for point to point (PtP) shots (mostly backhaul), and then uses unlicensed gear for point to multipoint (PtMP) that operates in 5 GHz spectrum.

The equipment
BridgeWave's radios operate in two bands. The 60 GHz units operate in bands in the 57 to 64 GHz range that are license free. The problem with these bands is that they are very susceptible to both rain fade and oxygen fade. The maximum range of BridgeWave units in this spectrum is listed as one mile (but that could vary if your location is very wet or very dry).

The 80 GHz units operate in two bands, 71 to 76 GHz and 81 to 86 GHz with what the company calls "lightweight licensing," in which you have to register your link in an online database and pay $75 for a 10 year license, but you don't get a license if you interfere with a pre-existing link. Jonathan Barker, CEO of QX.net, said that he's the only operator in Kentucky using the spectrum so the licenses come easy, and he likes the fact that subsequent users cannot degrade his links, which is an issue in the 5 GHz unlicensed spectrum. The 80 GHz units can have a range of up to 5 miles.

Radios in each category are available in several bandwidth versions: FE (Fast Ethernet) for 100 Mbps speeds, GE (Gigabit Ethernet) for 1 Gbps, AR (Adaptive Rate) that drops from 1 Gbps to 100 Mbps if there's a drop in signal level due to a very intense rain cell. X radios offer extended range with a larger antenna. U radios are upgradeable from 100 Mbps to 1 Gbps with a software key.

AES radios offer built in 256 AES encryption. Although the signals are on a tight beam and are therefore very secure, it can be easier to encrypt the signal instead of explaining to a customer that intercepting the beam would require physically breaking the line between the radio and receiver, both usually located far above the ground.

"If someone audits you, or if you have a breach," says Gregg Levin, BridgeWave senior vice president and chief marketing officer, "you want to be able to say that you're encrypted. We chose a price point, $6,900 list, at which people say it's worth it. We wanted to sell to a market beyond those that have to buy it."

Of course, the tight beams of these high bandwidth radios are inherently secure. "It's easier to tap into a fiber conduit than into a beam."

Customers worry about latency, he says, but BridgeWave's hardware encryption only adds 2 microseconds of latency. Total latency over a link is 40 microseconds.

The field upgradeable units, Levin says, give BridgeWave an entry into bids where other 100 Mbps radios are cheaper, but BridgeWave's offers a path to grow.

Go to page two: Selling the big links