The last mile has been a bottleneck of frustration for residential customers waiting for high-speed Internet access. While cable and DSL have helped slake some of the thirst for data, those services arent available in many markets. But the story is just beginning. Soon, the data-deprived will have more choices if service providers that have embraced fixed wireless technology have their way.

Fixed wireless, so named because it bridges the last mile with radio communication, has been enhanced by Federal Communications Commission (FCC) auctions making more of the public airwaves available to fixed-wireless providers.

Sprint and WorldCom pave the way

Two of the largest fixed wireless service providers are Sprint and WorldCom, who in 1999 spent about $2 billion each to purchase a total of 30 percent of the countrys Multipoint Multichannel Distribution Service (MMDS) licenses.

NextNet Wireless  Expedience CPE unit 

MMDS is located within the 2.1 GHz to 2.7 GHz range, and a single radio tower typically provides about a 35-mile rad-ius of coverage, depending on the type of terrain. Although it is considered a line-of-sight technology, it differs from LMDS and other millimeter-wave services, which have about a two-mile radius, in that its signal bounces off obstructions, rather than being absorbed by them. It is also referred to as a point-to-multipoint system, meaning that a company can erect a tower, usually in the highest location in the middle of a town, and transmit via microwave to homes and businesses across the 35-mile radius.

Sprint and WorldCom were set to merge back in 1999, but the merger fell apart last year because of regulatory concerns in Europe and in the U.S.

In May 2000, Sprint brought its technology to market when it announced fixed-wireless services for consumers in its first market in Phoenix and subsequently rolled out service in Denver and Colorado Springs, Colo.; Tucson, Ariz.; Detroit; Houston; San Francisco and San Jose, Calif.; and Wichita, Kan.


Were the real deal when it comes to MMDS, says Evan Conway, vice president of marketing. As far as deployment and product offering, were way ahead of everyone.

Sprint employs a super cell architecture, generally consisting of a single tower in town. It uses network equipment provided by Cisco Systems, Hybrid Networks and ADC Telecommunications.

ADCs Axity  wireless access system

However, last December Sprint announced it would stop selling its wireless Internet service to residential customers in Detroit because costs were too high, and because it wanted to wait for improved technology that would enable the company to reach more people. Part of the problem, a company spokesman said, was having a clear line-of-sight to the tower.

Sprint considers the technology its using in its current markets to be first-generation gear, and that the vendors are working on second-generation technology that should be deployable by the end of this year, says Conway. We feel pretty comfortable were OK for this year even just with current technology, says Conway. But were basing this new technology on a little bit more of a cellular design, where the current technology is sort of a super cell.

Sprints biggest cost in the current technology is in the CPE (consumer premise equipment) or receiver, which currently costs about $500 per subscriber, Conway says.

In November, WorldCom rolled out its first fixed-wireless service offering in Memphis, Tenn. It also announced plans to roll out in 29 more markets nationwide by the end of this year. Like Sprint, the company is deploying a super cell technology, which covers a 35-mile radius.

WorldCom is working with Hybrid, ADC and Nortel Net-works. It initially launched in Memphis on a Hybrid platform, will soon be moving to a Nortel platform, and has been working in test markets with an ADC platform, says Kerry McKelvey, COO of WorldCom Broadband Solutions.

Were still continuing to try different technologies and different platforms, says McKelvey. I think whats very positive is the service were offering is very much in demand by the marketplace. Its nothing thats overly complex. Its really quite simple and can be offered by these different platforms.

There is a lot of discussion in this industry as to the type of equipment that systems integrators like ADC, Hybrid and Cisco are providing to Sprint and WorldCom. Sprint and WorldCom both admit that the next-generation technology they are working on with their vendors is non-line-of-sight technology like OFDM (orthogonal frequency division multiplexing), which splits the data stream into multiple RF (radio frequency) channels, each of which is sent over a subcarrier frequency.

Systems integrators

Cisco, ADC and Hybrid are fixed wireless systems integrators that provide turnkey systems to service providers like Sprint and WorldCom using their own equipment and integrating other vendors equipment.

Cisco started shipping a multipoint MMDS solution last year that incorporates the modem into the companys UBR7200 router at the headend with a WT2700 interface. It is DOCSIS based and can run on IP-based services, says Troy Trenchard, director of marketing for Cisco.

The most important aspect of the WT2700 interface is that it embodies VOFDM (vector orthogonal frequency division multiplexing) technology. VOFDM was designed to stream high-speed voice, video and data more easily through congested city, suburban and rural environments by minimizing the line-of-sight limitations and installation problems faced by other broadband wireless access technologies.

Map of WorldCom licenses.

Cisco so strongly believes in its VOFDM technology that last year it joined with several other companies to develop open technology standards based on VOFDM for wireless broadband Internet services. The companies formed the Broadband Wireless Internet Forum (BWIF). Members of that group include Broadcom Corp., Texas Instruments, Motorola, Samsung, Toshiba, Pace Micro Technology, Bechtel Telecommunications, KPMG Consulting, LCC International and EDS. BWIF members agree to license to other BWIF members the technologies required to implement the standard on a worldwide, royalty-free basis.

Although Ciscos primary focus is on building Layer 3 network routing and relay equipment, Trenchard says, the company also sells products that implement Layer 2 technology with its VOFDM product. We deliver differentiated value-added services at Layer 3 and above, says Trenchard. While we sell product that implements Layer 2, we fundamentally believe that standards are what help drive robustness and cost points that make markets happen.

Cisco is building its first generation of MMDS equipment, says Trenchard. But the equipment is based on product it has been shipping for years, he argues.

Peter Jew

ADC offers service providers its Axity Broadband wireless access system, touted as a carrier-class architecture for two-way delivery of communications services over the 2.5 GHz MMDS spectrum. We deliver the kind of bandwidth that is comparable to a cable modem, says Peter Jew, ADCs director of marketing. We leverage a lot of the cable modem industry technology to gain critical mass a lot sooner using our approach versus someone starting from scratch.

WorldCom is in the midst of a technical trial using ADCs Axity system in Boston. It is also the first test of multicellular technology, says Jew.

Other wireless operators, including Evertek in Everly, Iowa and Valley Communications in Aberdeen, S.D, are also using the Axity equipment.

ADC is on its second generation of equipment, says Jew. ADC says its future generation of equipment will be able to use multi carrier technology, but that would still take some time to develop.

ADC works with Vyyo using Vyyos modems and hubs. Vyyos broadband access systems consist of wireless hubs located in base stations and wireless modems that connect to subscribers PCs or LANs. Vyyos equipment supports multi cell technology, says Arnon Kohavi, Vyyos SVP of strategic relations.

ADC and Vyyo joined with four other companies to form the Wireless DSL Consortium. The other companies include Conexant Systems, Gigabit Wireless, Intel Corp. and Nortel Networks. Similar to BWIF, the groups goal is to create MMDS standards.

One of the compelling stories we have, compared to our competition, is that we can offer a very clear evolution today, says Kohavi. If you buy our equipment today, you wont have to throw it away in the future. Youll be able to upgrade it relatively easily to provide a non-line-of-sight solution.

Diagram of high-speed access with ADCs Axity system.

Hybrid designs, manufactures and sells broadband data systems to network operators or ISPs. Hybrid products include the headend equipment used by the operator and the cable modems or wireless broadband routers used by the subscribers.

The companys largest customer is Sprint. Hybrid is supplying Sprint with fixed wireless modem and router products for its MMDS service in Phoenix and Tucson. WorldCom, on the other hand, uses Hybrids equipment in two of its four trial markets. Sprint used Hybrid cable modems in trials in Arizona, and hired Hybrid for the systems it is building in Denver, Colorado Springs, Detroit, Houston, San Francisco, San Jose and Wichita.


Sprint has essentially put the Good Housekeeping Seal of Approval on Hybrid the company and on MMDS the technology, says Michael Greenbaum, president/CEO of Hybrid.

The Hybrid system uses asymmetrical transmission that divides the 6-megahertz channel into three subchannels. To date, it supports only the transmission of databut the company plans to support voice service by the end of this year.

Hybrid is on its fourth generation of equipment, says Greenbaum. The company wants to continually evolve the equipment that is out there so that it doesnt have to force its customers or its customers customers to abandon equipment because it no longer fits with the network. Its next generation of equipment will address the line-of-sight issue through modulation and antenna diversity, says Greenbaum.

Wireless home market

Although Sprint is focusing its rollout on residential customers and small- to medium-sized businesses, and WorldCom is focusing mostly on the business market, a Minneapolis company called NextNet Wireless is quietly beta testing a plug-and-play desktop CPE unit called Expedience that eliminates costly truck rolls.

We came along as a start-up company, with a vision of what we were going to design into the system from scratch, and we put it together that way, says Barbara Heine, marketing manager of NextNet Wireless.

Capital costs for some fixed wireless systems run between $400 and $500 in the residential market. But NextNet claims its technology, excepting the set-top box and antenna, can be deployed for less than $100 per subscriber. The cost of its CPE will be between $350 and $450. The CPE also uses OFDM radio transmission and TDD (time division duplex) frequency modulation. TDD uses a single channel for both upstream and downstream communications, and automatically adjusts the amount of time used for sending and receiving.

The simplicity of the equipment drives the cost down, Heine says. The Expedience equipment consists of the desktop CPE, which connects to the subscribers PC and plugs into the wall outlet for power, and a base station.

The company wouldnt comment on which service provider is beta testing its equipment, but expects to make a deployment announcement soon.

Viable alternative to DSL or cable modems?

Whether for commercial or consumer use, fixed wireless technology offers a competitive alternative to cable broadbandin the same way cable offers another option to telco-controlled copper wires. As the flurry of fixed-wireless rollouts show, service providers like Sprint and WorldCom arent waiting to hedge their bets. While the current generation of technology has its limitations, Sprint and WorldCom are approaching the market with the attitude that they need to sign up customers for their service now, and then continue to hone the technology with their vendors.

James Mendelson of the Strategis Group says he is bullish on MMDS subscriber growth in 2001, but that the overall movement of the MMDS market will depend on how quickly Sprint and WorldCom deploy their systems.