What Factors Should Operators Consider When Planning WiMAX or TD-LTE Networks?
While recent media attention has further stirred the debate around WiMAX and TD-LTE, operators must carefully consider business models and deployment timeframes when planning their 4G network roadmaps.
The discussion was highlighted in a recent webinar by Maravedis Research as part of the Q1 2010 update on their 4GCounts Quarterly Report. According to Maravedis, while the number of WiMAX base station declined 10.9 percent from 2008 to 2009 due to operator uncertainty, the WiMAX ecosystem remained strong with over 5 Million WiMAX chipsets shipped in 2009 (332 percent Y/Y increase), WiMAX/BWA revenues of $3.03 billion (79 percent Y/Y increase), and 2.3 million new subscribers added in Q1 2010, bringing the total BWA/WiMAX subscribers to 7.2 million at the end of the quarter.
Indoor modems represented the lion share of the WiMAX device mix, accounting for over 3.6 million or 62% of subscriber units, followed by 1.1 million USB dongles and 528,000 PCMCIA cards. While mobility is important for many operators, most WiMAX users continue to use the technology as a fixed and portable broadband service.
Operators also remain apprehensive about their migration strategies and are looking for assurances that the technology they have selected will not become obsolete. Recent announcements by WiMAX Russian operator Yota that they had decided to switch to TD-LTE, as well as the recent exit of WiMAX operators Freedome4 in the UK and WorldMax in Amsterdam only add to the these concerns.
"Carriers are worried about the perceived lack of commitment towards 802.16m," said Maravedis Research Director Adlane Fellah. "However despite the hype surrounding TD-LTE, we do not see much of an ecosystem in the near term."
Despite the success of recent operator trials, by most accounts a commercially viable TD-LTE ecosystem is still several years away. Therefore for operators planning to deploy WiMAX or TD-LTE, the two most important factors are the operator's business model and the timing of when they are planning to deploy their network.
For existing WiMAX operators focused on the fixed and portable markets, sticking with WiMAX and incorporating some of the new upcoming features with "803.16e enhanced" makes the most sense according to Jonathan Jaeger, WiMAX Solutions Marketing Director for Aviat Networks. This is especially true for operators that own 3.5GHz spectrum which is not well suited for full mobility and for which TD-LTE spectrum profiles have not been defined.
"TD-LTE is still in a pre-commercial phase from an infrastructure an device perspective," says Jaeger. "For the next 18-24 months, 802.16e and 802.16e enhanced is the best path for operators planning to deploy in this timeframe."
For new operators planning to deploy now or in the next 18-24 months, and where full mobility is not the primary driving factor, WiMAX would also continue to be the best option. The WiMAX ecosystem is well established and both infrastructure and device costs are low and continue to decline.
For operators planning to deploy in 18-24 months (early 2012) AND mobility is a significant part of the business case, then TD-LTE may be an option to consider says Jaeger.
Cintia Garza with Maravedis in earlier comments also indicated the dilemma that operators are facing. "Spectrum winners, especially those in India, cannot afford to wait 2-3 years before deploying TD-LTE while WIMAX deployments move forward," said Cintia Garza, 4GCounts Team Leader. "If a carrier deploys WiMAX now with the intention of migrating to TD-LTE in the future, a significant challenge emerges regarding how to manage the millions of WiMAX device users."
To alleviate operators concerns, a number of telecom equipment vendors such as Motorola are offering RF base stations that are software upgradeable to other 4G technologies such as LTE. However, Aviat Network's Jonathan Jaeger cautions that the base station is just one part of the network and that operators should plan their migration strategy based on the entire network including spectrum, subscriber units and network elements such as the ASN gateway.
Although carriers like Clearwire are the exception with over 100MHz of 2.5 GHz spectrum in most of their markets, many global operators have only 20-30MHz of spectrum and are therefore limited in how they deploy their networks. Operators with large spectrum positions can add network overlays as new technologies mature, but operators with smaller spectrum positions would not have these options.
While decisions around the network infrastructure are important, how an operator plans to manage the multitude of customer subscriber devices based on a potential technology change can have a huge impact. Providing base software upgrades and migrating network components is one thing, but swapping out and replacing thousands of customer devices can quickly drive OPEX not to mention disruptions to customers. Dual mode WiMAX/LTE devices based on chips from vendors such as Beceem are also planned for release in 2011 that will enable subscribers to access both networks will certainly help.
