The WiMAX ecosystem is just months away from realizing its goal of seeing WiMAX Forum-certified equipment based on the 802.16-2004 standard come to market. However, many companies working with WiMAX technology already have another target in mind.

Initial WiMAX applications using technology based on 802.16-2004 will be fixed broadband applications, delivering WiMAX bandwidth to stationary targets. But, in a few months, the IEEE will approve the next standard in the 802.16 family — 802.16e. It's an amendment to the existing 802.16 standard allowing the benefits of that standard to be applied on a mobile, or nomadic, basis. It often can take two years or more for a new technology standard to evolve for commercial applications, but many companies, including Airspan, Alcatel, BT, Navini Networks, NextNet Wireless, Samsung and others, already believe that 802.16e — being dubbed Mobile WiMAX — has greater potential than Fixed WiMAX as a technology that can be molded to address the evolving broadband needs of consumers.

“We're keen to get started on 802.16e,” said Mick Reeve, group technology officer for BT. “The jury's still out, of course, but mobile/nomadic could represent a much bigger market. You could eventually see some vendor consolidation around 802.16e.”

Maravedis Telecom Market and Research Analysis recently issued the report, “WiMAX and Broadband Wireless (Sub-11 GHz) Worldwide Market Analysis and Trends 2005-2010,” which predicts that there will be more than 16 million Mobile WiMAX users within the next few years and that Mobile WiMAX chipset revenues could reach more than $700 million by 2010.

Vendors also are aware of the potential. Thus far, Alcatel's WiMAX strategy has centered on a partnership to resell Alvarion's Fixed WiMAX equipment, but Bruno Potdevin, vice president of business development and marketing for broadband wireless access activities at Alcatel, said the vendor giant is marshalling its resources toward 802.16e.

“We could have done a base station for the fixed market, but we wanted to shoot directly for 802.16e,” he said. “We're putting all of our research and development efforts into 802.16e. We are going to work with Alcatel's access unit to create a seamless evolution from DSL to nomadic broadband using 802.16e.”

Some companies see the specification as a method for telcos to expand their current broadband offerings by packaging DSL services with a so-called “personal broadband” capability.

BT, the U.K.-based carrier giant, currently doesn't have a cellular operation, so a service based on Mobile WiMAX could fill a need, even for a voice-over-broadband solution, Reeve said. “We want to think of voice as a multimedia application,” he said. “Ideally, we want seamless handover and low latency. We want the ability to do a handover between WiMAX and Wi-Fi and DSL.”

Mobile WiMAX also could potentially be deployed by mobile network operators as a complementary or auxiliary solution to 3G — or even as a 3G replacement. “Mobile operators could employ a WiMAX access network independent of the underlying cellular network or they could employ a WiMAX radio interface tightly integrated with the underlying cellular network,” said Peter Rysavy, principal at Rysavy Research at a recent WiMAX Forum quarterly members meeting in Malaga, Spain.

Though many mobile operators already have made choices about how they will progress to 3G mobile broadband environments, some companies working with Mobile WiMAX still believe there is an opportunity to position Mobile WiMAX somewhere in the 3G evolution. They point out that some large mobile carriers — Nextel Communications being a prime example — own a lot of spectrum that could be applied to a Mobile WiMAX deployment. (Nextel also has been viewed in the past as a Mobile WiMAX target because it didn't have a clear 3G strategy, but with its pending merger with Sprint, that's likely to change.)

Korea is currently the most advanced market in the world for both fixed broadband and 3G mobile broadband services, but Korean vendor giant Samsung is guiding that market toward Wibro, a proprietary solution very much like Mobile WiMAX. In fact, Samsung recently joined the WiMAX Forum to ensure interoperability between Wibro and Mobile WiMAX, according to Jung-Shin Park, head of Wibro/WiMAX developments at Samsung.

“Wibro's success is important for the success of Mobile WiMAX,” Park said. “Wibro will launch commercially next year and will help grow the momentum for Mobile WiMAX.”

Encouraged by increasing excitement over 802.16e from service providers and vendors, the WiMAX Forum has begun working on technical certification requirements for testing of conformance with the 802.16e standard, as well as interoperability. The WiMAX Forum also recently launched a Mobile WiMAX Positioning Task Force to study how the technology should be positioned in the broadband market relative to other broadband technologies

“We want to clarify a lot of confusion about what Mobile WiMAX really means,” said Sai Subramanian, vice president of product management and strategic marketing for Navini Networks and also chairman of the task force. He said he believes that for Mobile WiMAX to be successful, it must avoid being referred to as a “cellular alternative.”

“WiMAX is personal broadband,” Subramanian said. “To succeed on its own terms, it has to have broad bandwidth, it has to have the right service economics and it has to offer something more than DSL or cable. What it can offer is the freedom to get broadband anywhere.”

Subramanian said the model of using Mobile WiMAX for expansion on top of existing broadband solutions, such as DSL and cable modems, can help solve what has been one of the most pressing problems for broadband service providers — making broadband availability ubiquitous in semi-suburban areas beyond the urban cores and more dense suburban areas where it has thrived.

Whether Mobile WiMAX will evolve as a personal broadband extension of existing broadband networks or as a complement or alternative to existing mobile 3G networks remains to be seen. The companies trying to carve out a future for Mobile WiMAX may have more time to figure that out than they would like. Ultimately, the WiMAX Forum can't develop the details of a certification agenda for a technology that isn't fully standardized, so it will be at least a few more months before the forum's plan for Mobile WiMAX certification becomes clear.

“There is no 802.16e certification profile today,” Park said. “It is important that this happens as early as possible.”

The great excitement over 802.16e, and to some degree, confusion about how it will be deployed, could affect the more imminent deployment of equipment based on the 802.16-2004 standard. In short, carriers may not want to deploy Fixed WiMAX so quickly and extensively if Mobile WiMAX is not so far away.

Some sources connected with 802.16e have said that one or more semiconductors producing Fixed WiMAX chipsets will only issue a single generation of these chipsets before moving on to develop Mobile WiMAX chipsets.

Service providers hearing that Mobile WiMAX is the best thing since sliced bread also are now trying to ensure that vendors of Fixed WiMAX equipment can provide them with “some kind of soft ‘upgrade-ability’ to 802.16e,” as one official with a service provider recently put it.

The source added, “We don't want to put [Fixed WiMAX] equipment into our networks now that we'll have to rip it out in another two years when the next best thing [Mobile WiMAX] comes along.”