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Rushing for unlicensed spectrum

Wed, 01/31/2001 - 7:00pm
Michael Lafferty, CED Associate Editor
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When it comes to blazing new trails in alternative broadband delivery technologies, fixed broadband wireless has hit its fair share of potholes. In fact, some would say its not all that surprising that the overblown hype surrounding MMDS and LMDS spectrum auctions a few years ago helped drive the technologies over a cliff a short time later.

But, that was then...This is now.

My overall take on fixed wireless is that there are a couple of things coming together right now that might really help advance this market, says Michael Greeson, consulting analyst for Parks Associates. One is the DSL meltdown. A lot of the DSL providers and competitive carriers have just not been able to deliver on their promises that they made. And because of whats recently gone on in terms of market valuation of some of these young companies, theyve had to literally pull back their deployment plans.

Greeson notes that hes been following the travails of DSL providers and their frustrated customers. Multi-million-dollar class-action suits are just the latest tools some are using to try to force DSL and cable providers to live up to their broadband promises. All this, says Greeson, means new opportunities for alternative broadband approaches like fixed wireless.

Its kind of a unique market right now, explains Greeson, in terms of some of the opportunities that are presented to alternative broadband technologies such as fixed wireless or satellite technologies.

What Im seeing are some marketing attempts on the part of people in the fixed wireless space, not the providers themselves, but the equipment manufacturers, to use that as a marketing tool to some of these smaller carriers that are looking for quicker ways to get to market. And fixed wireless is certainly legitimate technology to get you into the market really quickly and overcome a lot of the difficulties associated with co-location and last-mile problems that some of the CLECs and incumbent providers are running into.

The apparent resurgence of MMDS, and to a lesser degree, LMDS technologies, in North America has come at a cost, though. The recent flurry of spectrum license acquisitions in the MMDS/LMDS space by telco behemoths WorldCom and Sprint has been estimated to cost more than $2 billion. Those kinds of license costs are a nut that many potential or incumbent service providers cant swallow and still remain standing.

U-NII: license-free opportunity?

The headline-grabbing hubbub over MMDS and LMDS spectrum auctions of the not-too-distant past and the more recent billion-dollar reshuffle of those licenses overshadowed a few small slices of license-free spectrum tucked away by the FCC. The Unlicensed-National Information Infrastructure (U-NII) consists of two pieces of airwaves in the 5 GHz range.

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Thats right...No license auctions, no government forms, no moolah moving to Washington D.C. Quite a concept, huh?

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Trenchard

The FCC put aside 300 MHz of spectrum, explains Troy Trenchard, director of marketing at Cisco Systems. Theres 200 MHz at the low 5 GHz range (5.15 GHz to 5.35 GHz), and 100 MHz up at the 5.7 GHz range (5.725 GHz to 5.825 GHz). The lower frequencies, because of the power limits, are really more appropriate for indoors or very localized use. But the 100 MHz in the upper end of the spectrum, the power is such that you can do wide area communications.

Trenchard says that while the spectrum is free for anyone to use, it does have some technical limitations, as well as a few fuzzy interference regulations imposed by the FCC. He says the U-NII band has certain maximum power levels that must be adhered to. Unlike MMDS, which can send signals 20 miles or so, U-NII powering restrictions keep its cell size in the three- to five-mile range. Interference in the band has also been addressed by the FCC, if somewhat vaguely, says Trenchard.

Other than your equipment must comply with the FCC regulations, says Trenchard, there are no pre-requisites. You dont have to go license yourself with the FCC or anybody. However, there are maximum power levels and certain basic rules about how any equipment must deal with interference, which most likely will be somebody else already transmitting in a subset of that 100 MHz.

There are what I would call good citizen rules that say that anyone who builds or operates equipment in that 100 MHz has to operate by those basic good rules. The FCC has specified, at a very high level, interference arbitration. So, if you have a case where somebody has a service in this spectrum and somebody else turns on and its suddenly interfering, causing this other companys traffic not to work properly, the FCC has indicated that there will be an arbitration process. Although, it isnt very clear how that arbitration would work.

Does all this make the U-NII band untenable for broadband fixed wireless? No, says Trenchard. In fact, its just the opposite.

Whats really going on here is actually quite interesting, says Trenchard. In the upper U-NII band at 5.7 GHz, theres a rush to market by a number of service providers to get into markets, establish themselves, and get customers before the competition shows up.

What I expect to see is aggressive companies getting to market. We see that and were working with a number of them already. What I expect to see in many markets is one or two players, but not five, because it will be very hard for five players to make a go of it.

While a number of start-up companies have begun to latch onto U-NII band opportunities, Trenchard says theyre not the only ones.

The most aggressive right now are what you would call startups. These are companies that may have been in business doing something else, not necessarily in the wireless space or maybe not even in the service provision space.

But the exception to that, and were just starting to see a growing interest from them, is from cable providers who are in the business of providing services today. But, they are fundamentally limited to whom they can provide service because of their plant. Suddenly, you have cable operators saying, I could use my incremental facilities and provide services to a different segment of customers that I cant physically reach with my plant today.

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Ciscos wireless products support multiple frequency bands, including U-NII,  standardized on VOFDM and DOCSIS.
A case in point

One U-NII band provider is DATACentric Broadband, based in Lake Conroe, Texas, just outside of Houston. Its decision to provide high-speed broadband access in the unlicensed band in non-NFL cities was directly tied to licensing fees in other bands, says Russell Buras, DATACentric president and CEO.

We operate exclusively in the license-free bands, says Buras. We dont want to go out and spend the dollars to buy the licenses and the equipment to go with them. Were currently in Texas, and thats probably where were going to be at least this year, but were looking to go beyond that.

The company provides scalable-on-demand bandwidth speeds ranging from 256 kbps to 100 Mbps to businesses right now with point-to-point data using fixed wireless data networking equipment from Adaptive Broadband.

Buras says U-NII band service serves up a number of advantages for its providers. For the provider, says Buras, because it is leading edge and it requires technologists or engineers to deploy, its not plug-and-play from a network standpoint. But, it does provide time to market and we can deploy quickly.

Obviously, there are also some cost benefits. And, as a service provider, you can manage your own network. Youre not dependent upon other providers. Thats the thing we really like.

Todd Carothers, vice president of marketing for Adaptive Broadband, says that DATACentrics targeting of businesses and municipalities makes a lot of sense at this early point in the U-NII game. The markets that DATACentric and a lot of our customers are in, explains Carothers, the end users are paying anywhere from $100 or $200 up to $600 for low data rates with 64 kbps/128 kbps lines, which, by the way, are erroneously being termed as broadband. Our customers are going in there and telling them that its nonsense, and that for the same price theyll give them 2 Mbps.

Carothers says such business revenues will help U-NII band providers to pay for their infrastructure. And, much like the way the cell phone business expanded, once the infrastructure is in place, they can go after more markets with more services like voice-over-IP, video and virtual private networks (VPNs).

I see the revolution, says Carothers, in replacing a lot of those problems that are there (with wire line solutions) because wireless can go anywhere. Its just a matter of building the infrastructure. Thats why U-NII is so key, and I think thats why weve seen a great success in U-NII is because of the fact that its unlicensed. Its easier for people to get out there and be able to deliver access today.

Bandwidth battles

As with any new technological approach, U-NII band proponents have differing opinions on the best way to deliver broadband access over the airwaves. Bandwidth efficiency and the various components it takes to achieve it is a hot topic of conversation in U-NII circles.

Added to that are the various flavors of equipment the manufacturers are producing in the fixed wireless market. First-generation equipment has the ability to serve line-of-site (LOS) locations. Second-generation equipment will work on obstructed line-of-site (OLOS) locations. And most desirable, third-generation equipment will serve non-line-of-site locations (NLOS).

At this point, two camps seem to have surfaced, both of which have formed consortia to promote their points of view. In one corner is Cisco Systems and its associates, and in the other corner is Adaptive Broadband and its supporters.

The Broadband Wireless Internet Forum (BWIF), formed by Cisco, is in business to promote an open RF wireless Internet standard, based on a variant of the DOCSIS Media Access Control (MAC) Layer and a Vector Orthogonal Frequency Division Multiplexing Physical Layer (VOFDM) for broadband wireless services.

Adaptive and company believe the DOCSIS MAC with its dedicated channels and its inherent frequency division duplex (FDD) approach is inappropriate for the wireless world. As such, it will need to be modified for wireless to a point where it varies greatly from the cable modem variant.

Adaptives MAC answer is a single shared channel where bandwidth is allocated as single cells with variable priority according to user class and traffic type. Adaptive believes time division duplex (TDD) is more efficient because it groups all of the available bandwidth into a single radio channel which is then switched rapidly from upstream to downstream as needed to handle the presented load.

VOFDM is a variant of OFDM, which breaks up available spectrum into orthogonal sub channels. The V for vector in VOFDM adds the value of spatial diversity according to the BWIF group, which allows either one or two antennas to take advantage of multiple signals created by the multipath (bounced signals) capability. Adaptive, meanwhile, believes time division multiple access (TDMA) with a dynamic equalization scheme can handle multipath fade and NLOS locations.

In all probability, the debate between these two camps will probably be settled by the newly established WirelessHUMAN (Wireless High-Speed Unlicensed Metropolitan Area Networks) project created within the IEEEs 802.16 Working Group on Broadband Wireless Access.

The IEEE says the newly-created Task Group 4 will base its WirelessHUMAN standard on modifications of the IEEE 802.16 medium (sic) access control layer, while the physical layer will be based on the OFDM mechanism of IEEE 802.11a and similar standards. The task group has already issued a public Call for Contributions.

Going public...finally

While the U-NII band has never been an official secret, its flown under the radar of many companies and individuals, until now. Given the ever-increasing competition in telecommunications, says Carothers, its really no big surprise that the benefits and opportunities to be found in U-NII band service have been nearly invisible. But, he thinks that is going to change fast.

Thats because this is a stealth industry, says Carothers. Its not only stealth for the equipment providers, but its also stealth for the service providers. They dont want to talk.

Its just so competitive and all of the funding wraps around the business plan and where theyre going to go, etc. Were finding now that because of the current market factors, some of VC (venture capitalist) funding has slowed down in the ISPs and CLECs because theres some volatility there.

But the guys with the good business plans are getting the funding. So, those are the guys that are going to be even more aggressive. And I think youre going to see a lot more happening publicly. Theres been a lot happening privately up to this time. And, I think youll start seeing some consolidation, not only in the service provider arena, but in the equipment side of things as well.

E-mail: mlafferty@cahners.com

 

U-NII band resources

A brief, and incomplete, list of Web resources of companies and organizations involved in the development of U-NII band products, services and standards now or in the near future.
Adaptive Broadband - www.adaptivebroadband.com
Aperto Networks - www.apertonet.com
BeamReach Networks - www.BeamReachNetworks.com
Broadband Wireless InternetForum - (BWIF) -www.ieeeisto.org
Cisco Systems - www.ciscosystems.com
DATACentric Broadband - www.databb.net
IospanWireless (formerly Gigabit Wireless) - www.iospanwireless.com
Malibu Networks - www.malibunetworks.com
Nextnet Wireless - www.nextnetwireless.com
Raze Technologies - www.razetechnologies.com
Wireless Networks Online - www.wirelessnetworksonline.com
WirelessHUMAN Project-  www.wirelessman.org/tg4/index.html

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