With 3G finally beginning to live up to its hype, it may seem a bit silly to even begin discussion of the U.S. wireless industry's evolution to 4G. After all, while the major distinction of 4G over 3G is the former's accelerated data transmission rates, many of the services promised by 4G — mobile multimedia and streaming video among them — are already available via 3G, albeit in more primitive formats, and consumers aren't exactly standing in line to sign up.

But as they say, you can't stop progress. According to Visant Strategies' recent study “The Road to 4G and NGN: Wireless IP Migration Paths,” the 4G market will begin taking off in the next 12 to 24 months, totaling 113 million global users by 2010. And while neither operators nor their subscribers may be ready and willing to make the leap to 4G, a clutch of U.S. mobile broadband vendors is waiting in the wings, fine-tuning their portfolios with deployments and trials both at home and abroad, most notably in an Asian wireless market well advanced of its western counterpart.

But there's a catch: Seemingly no one agrees on what 4G represents, when it's coming or whether such a thing even exists. Here are four vendors on the subject of 4G.

ArrayComm: “I've heard the term ‘4G’ used in a variety of contexts,” said Mark Goldburg, chief technical officer with personal wireless services developer ArrayComm. “There are all kinds of standards groups working toward some next generation of cellular technology, so it might be that. Alternatively, it might be a service vision. But the 4G service vision hasn't changed much from that of the original 3G service vision that got people so excited and created the expensive spectrum auctions and resulted in the allocation of more spectrum here in the U.S. and elsewhere.”

Founded in 1992 by Martin Cooper, inventor of the first portable cellular phone, ArrayComm is best known for developing iBurst, a broadband wireless system promising 1 Mb/s data rates. Powered by the company's IntelliCell smart antenna technology, which adds a unique spatial metric to each transmission that effectively reuses the same channel multiple times over, iBurst delivers 400 times greater capacity than current wide-area wireless systems.

ArrayComm's technology is presently deployed in more than 225,000 base stations, serving more than 15 million people across four continents. Goldburg stresses that despite its proprietary stake in the iBurst protocol, ArrayComm is in fact standards-agnostic, and its smart antenna technology will work over any network, be it 802.16e, 802.20 or 3G.

“People say, ‘You're in the iBurst business, and you're in the .16 business — aren't you competing with yourselves?’ But both solutions are targeted at different market segments,” he said.

In fact, ArrayComm's success or failure will hinge most of all on the adoption of smart antennas.

“Broad acceptance of smart antenna technology is what's necessary to differentiate WiMAX from W-CDMA,” Goldburg said. “WiMAX is much more amenable to smart antenna processing, and that's where people think they'll get big gains in economics and performance over 3G. The market has to recognize that smart antennas are necessary for cost-effective mobile broadband.”

Flarion Technologies: “There is no such thing as 4G — there's just what's beyond 3G,” said Ronny Haraldsvik, vice president of marketing and global communications for Flarion Technologies. “A move from circuit-switched to packet-switched is what this is all about — we're unwiring what already exists. You're going to see wireline Ethernet become wireless Ethernet. The business case is lower cost of network operations, improved capacity and speed, and access to new revenue sources.”

Flarion is synonymous with Flash-OFDM (orthogonal frequency division multiplexing), an IP-based mobile broadband standard that claims speeds of up to 1Mb/s. In February, the company released upgraded Flash-OFDM gear targeting triple-play IP services over mobile networks, debuting a new platform dubbed Flexband that promises a full 1 GB of data per subscriber each month.

“We have a system that can deliver one gigabyte of data consumption per user per month at a cost to the operator of $10 or less,” Haraldsvik said. “That means an operator can sell mobile broadband and IPTV and VoIP anywhere from $40 and up, and at less than two percent market penetration, you're breaking even with our network.”

Although Flarion's fortunes suffered a blow last month when Nextel announced it would end its Flash-OFDM trial in Raleigh, N.C., this summer, OFDM may still have the inside track on market dominance. According to “Hard Numbers and Experts' Insights on Migration to 4G Wireless Technology,” a recent report issued by Rysavy Research and Datacomm Research Co., the advantages of OFDM become more pronounced as networks achieve higher speeds. The study adds, however, that because CDMA networks — whether CDMA2000 or wideband CDMA — still have some distance to evolve, it will be several years before vendors must shift to OFDM.

“The market is moving toward OFDM because that's where it can find the scalability to deliver high-bandwidth data,” Haraldsvik said. “All of the major operators in the U.S. and elsewhere have come to the realization of what 3G can and cannot do. 3G does voice and some data services really well, but when you move to an all packet-switched system, you get scalability and lower-cost economics. In another two or three years, operators are going to come to the realization they need more capacity, too, so things may open up then.”

IPWireless: “We're staunch believers that 3G is going to be around for awhile,” said Jon Hambridge, senior director of marketing for IPWireless. “What 3G turned into has opened a window for people to start talking about 4G. When we look at what people want — and what people are starting to deliver over our networks — what a lot of people are talking about for 4G is getting confused with 3G. The next step for 3G is to be completely packet-based, to be IP-based and start to get up into the multi-megabit speeds. The vision of delivering multi-megabit services at very low cost in a mobile environment is more a part of 3G, and 4G is still a very long way away.”

IPWireless' mobile broadband technology is essentially a packet data implementation of the international 3GPP UMTS standard that uses time division duplex (TDD) to enable operation on unpaired spectrum. Since mid-2002, IPWireless has deployed 40 networks worldwide, delivering up to six to seven times the capacities of other 3G technologies.

“UMTS is the evolution of GSM, and 75% to 80% of subscribers worldwide are on GSM networks,” Hambridge said. “Both Asia and Europe have dedicated spectrum specifically for UMTS technologies, and all the big operators across Europe own 5 MHz of spectrum specifically for UMTS-TDD.”

According to Hambridge, the challenge facing IPWireless isn't another vendor or a rival technology — it's inertia.

“There is a defined set of mobile OEMs that are entrenched, and when you knock someone off their path, it always takes a little bit,” he said. “A lot of operators are still searching for the killer app that will justify spending $2 billion to deploy one of these networks. There's a lot of room across consumer applications, but can you offer someone a broadband service that not only makes them give up their hot spot service, but also their DSL line at home?”

Navini Networks: “The logical step for delivering [4G] is to change the nature of broadband,” said Sai Subramanian, vice president of product management and strategic marketing for Navini Networks. “We need to do for broadband what cellular did for phones and change broadband to something you have with you. We're making that possible today.”

A 5-year-old wireless broadband equipment vendor with customers in about 30 countries, Navini leverages phased-array smart antennas to provide portable plug-and-play access solutions that promise seamless evolution to the fledgling Mobile WiMAX standard.

“We've chosen Mobile WiMAX for two reasons,” Subramanian said. “First, the vision of Mobile WiMAX is consistent with what we're doing today, which is portable broadband. Also, it's being built from the ground up for broadband usage. We can leverage a key advantage over other vendors, which is all the technology we have wrapped around smart antennas. In the short-to-medium commercial range, WiMAX and other new technologies based around smart antennas will be the driving force.”

In late 2003 Navini partnered with service provider Unwired Australia to build what the company claims is now the largest non-line-of-sight commercial wireless broadband network in the world, covering more than 1200 square miles and 3.5 million potential users.

“Speculation is a dangerous business, but my view is that by next year, you will see some larger [4G] moves from the bigger players in the U.S.,” Subramanian said.

And is there such a thing as 5G on the distant horizon?

“Innovation never stops,” Subramanian said. “There are guys out there thinking about even more fantastic things than 4G. I would never be arrogant enough to say whatever we've dreamed up is the end-all.”

Commercial Mobile Broadband Deployments Worldwide*

ArrayComm

Australia

IPWireless

U.S.
Australia
Germany
Malaysia
U.K.
New Zealand

Navini

U.S.
Australia
The Netherlands
Italy
Panama
Malaysia
Ireland
Trinidad
Tobago

*Publicly announced deployments only

Source: Company Web sites