4G Network Deployments will Focus on Mobility - Last Mile

4G Network Deployments will Focus on Mobility
Last Mile
Bradley Kramer

Sept. 1, 2008

The next generation shall inherit the earth. That next generation looms around the corner in the form of high-tech communications as companies prepare for the fourth generation (4G) of broadband connectivity.

While public and private service providers continue to roll out today’s generation of broadband networks — consider Apple’s recent release of the 3G-enabled iPhone — those same providers are looking toward the next wave of access technologies, such as WiMAX and Long Term Evolution, better known as LTE.

WiMAX and LTE are fairly similar in terms of capacity and mobility, says Arthur Giftakis, vice president of engineering and operations of Towerstream, one of the first ISPs to become a member of the WiMAX Forum, which creates industry standards for WiMAX components. WiMAX and LTE are expected to provide high-bandwidth mobile service, and both are based on the same underlying data transmission technology, called Orthogonal Frequency Division Multiple Access (OFDMA), which allows for low data rate transmission from several users. 

“The difference between which one is better will be a battle of religions,” Giftakis says. “It’ll be a matter of what is the flavor of choice for service providers.”

The benefit that OFDMA has over older data transmission modulation like TDMA and CDMA is how data is transmitted over radio spectrum, says Ashish Sharma, vice president of corporate market development of Alvarion, a founding member of the WiMAX Forum. In essence, OFDMA slices spectrum into smaller individual channels, allocating a different channel for each user.

“The biggest advantage of OFDMA is it uses spectrum in a more efficient way,” Sharma says. “The amount of data transferred at any time is much more than TDMA and CDMA.” Sharma estimates that OFDMA doubles the amount of data that can be transmitted compared to older technology.

The determination for which 4G technology a service provider chooses will be largely based on their existing network infrastructure, says Erik Boch, CTO of DragonWave. WiMAX and LTE represent solutions for high bandwidth data services and purport to deliver similar end-user capacity. The difference, he says, boils down to the motivation to pick one over the other.

Network operators with existing cellular infrastructure based on the GSM standard (mostly in Europe) are more likely to choose LTE, Boch says, because LTE is based on cellular technology and was designed as a sort of roadmap from GSM to future network generations. It just so happens that the future came sooner than expected.

Because of its popularity among cellular operators, Sharma says that LTE has an advantage of being connected with incumbent providers.

WiMAX, on the other hand, is based on Ethernet protocol, Boch says. Network operators that do not have an existing GSM architecture and new entrants to the market are more likely to choose WiMAX for ground-up deployments.

In the end, the WiMAX vs. LTE decision will amount to a political debate, says Jim Orr, principal network architect in the wireless market development group at Fujitsu Network Communications. Service providers have already begun to declare their technology allegiances, as Verizon and Alltel have come out in favor of LTE, while Nortel and Alcatel-Lucent have chosen WiMAX. And in May, Sprint and Clearwire announced a partnership to deploy WiMAX as a joint venture.

This Generation

One advantage that WiMAX has over LTE is its expected time-to-market schedule, says Torbjorn Ward, CEO of Aptilo Networks. Deployments of fixed WiMAX networks have already been successful around the globe, and the WiMAX Forum continues to approve standards to ensure quality and interoperability between components. In order to enter the 4G world, WiMAX must incorporate mobility.

“LTE,” Ward says, “is at least two years behind mobile WiMAX.”

WiMAX has already been successful in wide area networks (WANs) in countries such as Korea, Japan and Malaysia. However, progress has been slow in the United States 

One reason for the discrepancy in WiMAX deployment between the United States and the rest of the world is because of the differences in overall broadband availability, Ward says. In the United States, there are many service and technology options, from wireless and wired access. However, in other countries, communications infrastructure is not always as well developed.

In some countries, if there is copper wiring in the ground, that infrastructure is not always reliable. In other cases, topographical obstructions have made it prohibitive to deploy any kind of underground wiring. Therefore, Ward says, it’s easier to deploy a new wireless network than a new wired system.

“WiMAX is much better suited for ground-up deployment than LTE,” he says. “Coming out of an industry from broadband wireless, WiMAX is more cost efficient.”

Another key issue for WiMAX deployment is whether service providers have enough radio spectrum, Ward says. Currently, the WiMAX Forum has certified 2.3, 2.5 and 3.5 GHz for WiMAX, and the soon-to-be vacant 700 MHz TV band may also be used.

Promised Generation

The promise of 4G networks is the promise of new possibilities, from advanced applications and consumer devices to closing the digital divide.

On the applications and devices side, the possibilities are endless, says Eran Eshed, vice president of marketing and business development of Altair Semiconductor.

As companies like Intel incorporate WiMAX capabilities into more devices, applications will be developed to suit consumer demand, which Eshed says will help speed adoption rates. Applications like mobile TV, personal navigation and music players will allow users to download content on-the-go. For instance, in-car navigation tools could receive real-time data from WiMAX networks, downloading maps and traffic data that are updated live.

Eshed expects 2009 and 2010 to be massive trial years for mobile WiMAX.

Last year, the broadband industry witnessed a severe scaling back of wireless deployments in the United States, specifically in the municipal market. Those wireless networks were mostly based on Wi-Fi hotspots, which in the end became too cost prohibitive to supply city-wide coverage for Internet access.

There are still many communities that lack access to broadband services, and WiMAX could help fill that void, Ward says. WiMAX offers better building penetration than Wi-Fi and provides similar range as cellular service, which makes it a better option for city WANs. 

The problem with new technologies is that adoption can be slow. For instance, 3G networks have been in deployment since 2001, but it wasn’t until 2006 that the 3G market began to take off.

Similarly, it will probably take five years for WiMAX to become a ubiquitous technology, Giftakis says. 

First, service providers must supply a ubiquitous network, at least full coverage in one city where the technology can take root and build appeal among its residents, Ward says. To get to the next level, the provider needs to achieve nationwide coverage. The final challenge will be developing WiMAX antennas that are small enough to be built into devices, but don’t drain battery power.

Initially, laptops will remain the prime device for mobile WiMAX, Orr says. Laptops continue be a strong delivery mechanism for broadband technology because they are big enough to house the technology and cost is not as prohibitive to consumers who are not ready to plop down $700 for a handheld gadget.

While consumers may not be ready to pay for expensive new gadgets, they are hungry for more bandwidth. Mobile WiMAX will help take consumers to the next generation of communications technology.