Reaching Out to 4G
Standards and definitions are still being worked out, but early entrants are forging ahead.
By Monica Alleven
February 1, 2007
Wireless Week
Talking about 4G when 3G is still being rolled out in the United States may seem like jumping the gun, but technicians and network planners are doing just that.
While standards bodies have yet to issue a formal definition of 4G, some central elements usually enter 4G conversations. Those include all-Internet protocol (IP) and peer-to-peer networking, along with technologies such as orthogonal frequency-division multiplexing (OFDM), multiple-input/multiple-output (MIMO) and software- defined radio (SDR).
Simply put, the services translate into lower costs and higher data speeds for end-users. In more industry-centric terms, however, WiMAX, long-term evolution (LTE) for GSM and ultramobile broadband (UMB) for CDMA are considered 4G technologies in some circles – although whether mobile WiMAX fits the definition is a subject of debate.
IN DEVELOPMENT
If the acronyms are getting too thick, it might be easier to grasp 4G by considering what one U.S. operator is doing. Sprint Nextel, with its WiMAX plans, is the only nationwide U.S. operator to map out its strategy thus far.
In another significant standards development last year, Sprint joined six other operators internationally to form the Next Generation Mobile Networks (NGMN), which is based in the United Kingdom. "We felt for a long time that operators needed to provide a more coherent view of what our requirements and needs were," says Steve Falk, vice president of global standards at Sprint.
Although other standards bodies exist, the NGMN effort is designed to accelerate the development of standards, he says. The group, which includes GSM and CDMA operators, is technology agnostic. Cingular Wireless, now being rebranded to AT&T (read more on Page 28), more recently joined as a member.
Besides facilitating the harmonization of new technologies, another aim of NGMN is to develop a more predictable intellectual property rights (IPR) regime. "I'm very pleased with the process so far," Falk says, with the objective not to deliver one technology but to guide principles going forward.
Sprint has been a leader in wireless data since 1999, when it launched its 2G Wireless Web nationwide, and "we think we still have that leadership position," Falk says. One of the big reasons for selecting mobile WiMAX was its time-to-market advantage. The plan is to roll out coverage to 100 million POPs by the end of 2008.
Sprint executives explain that they are making the Internet airborne, so whatever DSL-type speeds consumers expect from a desktop PC also are delivered in a mobile environment. Executives talk about embedding technology in everything from personal media players and game stations to more advanced navigation systems in cars.
In fact, Sprint has formed a separate business unit devoted to WiMAX based in the Reston, Va., area, drawing talent from the entire Sprint family. To speed decision making, vendors reside in the same offices. To be sure, "there's a lot of work to be done," says John Polivka, senior communications manager at Sprint.
Although vendors are not members of the NGMN, they are working with the operators. In the vendor community, as well as among operators, representatives express their desire to keep end-users top of mind rather than focusing too much on obscure numbers. Today, much of the industry's focus is on how many subscribers use a network and net additions, but in the future, that discussion is expected to shift to how many devices are connected to the network and move to any kind of electronic device, according to Scott Wickware, vice president of the carrier networks group at Nortel.
GETTING BUSY
It's too early to measure LTE or UMB contract wins, but Nortel currently has five active WiMAX trials on four continents and one commercial customer in Taiwan for the 16e version. "This year is going to be a very active year for everyone in the industry," says Bruce Gustafson, director of marketing for carrier networks at Nortel.
One of the more provocative ideas in 4G is opening the network so that instead of tying handsets so tightly to the network, more consumer electronics device makers could step in. It's unknown whether it will be two or five years down the line, but the idea is that at some point, a consumer could walk into a big-box retail store and buy an electronic device that isn't tied to a specific network, although the end-user likely will have some relationship with an operator and it will just show up as another device connected to his or her account, Gustafson says.
U.S. carriers are still investing in 3G, so why is it necessary to go to 4G? Besides needing to constantly keep up with advances in wireline technology, wireless engineers like to see how far they can go beyond the challenges and set a new bar for a lower-cost, higher-quality user experiences. "The wireless industry will rise once again," says Raghu Rau, senior vice president in networks and enterprise at Motorola. "I think it's just very reflective of the human spirit."
"Nothing is a stable target," agrees Paul Mankiewich, chief technical officer for North America at Alcatel-Lucent. "Everyone keeps improving, and the wireless stuff tends to lag behind, but wireless has the mobility."
As long as we're talking about the future, what about 5G? Nortel's Wickware quips that it's "something that comes after 4G and before 6G."
"G" Force
1G: Voice-based analog
2G: Digital voice
3G: Emergence of high-speed data
4G: To be determined, but "true" wireless broadband is an oft-cited goal
4G Promise?
The International Telecommunications Union (ITU) defines 4G as 100 Mbps while moving and 1 Gbps when stationary, but not everyone is convinced those data speeds are attainable in the real world.
The ITU's 1 Gbps may be a "blue sky" number that cannot be achieved in 4G, says J.H. Snider, research director of the Wireless Future Program at New America Foundation in Washington, D.C. Current cell sizes are too large to achieve such high data-rate improvements. He cites research by two engineers from AT&T Labs who calculated that AT&T may need to subdivide existing cell sites by more than a factor of 100, with cell sizes averaging only 1,000 feet in radius, to efficiently achieve 4G level bit rates.
To accommodate all of the antennas that are necessary in 4G will mean putting gear on light poles and telephone poles, he says, adding that municipal Wi-Fi probably is closer to 4G architecture than 3G.
Put another way, the promise of 4G is probably more closely tied to wireless broadband in that anything you can do on a computer plugged into the wall, you can do on a 4G device, says Rob Enderle, president of the Enderle Group.
NGMN Live!
When it launched last fall, the Next Generation Mobile Networks (NGMN) initiative outlined guidelines to help guide mobile networks beyond current HSPA and EV-DO technologies.
• High levels of data throughput alongside low latency levels
• Low operation and maintenance costs
• Compatibility with legacy networks
• Support of high levels of authentication and security; differentiated quality of service
• Improved terminal certification schemes
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