Looking at the WiMAX market today, it\'s clear that the battle between LTE and WiMAX is over. LTE has emerged as the next-generation network technology winner in the mobile operator community. And the majority of current WiMAX operators--which now number about 583 in 150 countries--have carved out their niche by offering DSL replacement services in their respective markets. However, these WiMAX operators need decide if WiMAX will be suitable for them down the road.

With the exception of big operators such as Clearwire (NASDAQ:CLWR) in the United States and UQ Communications in Japan, most WiMAX operators operate fixed or nomadic networks. That is reflected by the types of WiMAX devices available; of the 400 WiMAX-enabled devices available on the market, few are handsets and the rest are CPUs, M2M modules, USB modems, embedded laptops and a handful of tablets.

"What is happening is that you have WiMAX becoming solutions for backhaul, business connections and rural markets," said Mo Shakouri, corporate vice president of innovation and marketing at WiMAX equipment vendor Alvarion, in an interview with FierceBroadbandWireless. "At that level you have not seen as many big deployments of WiMAX but small ones with continuous growth."

Ron Resnick, long-time president and chairman of the WiMAX Forum, also concedes that WiMAX is playing second fiddle to LTE. However, he said in an interview with FierceBroadbandWireless that more than 30 WiMAX networks are currently being built around the world, many of which are small networks.

Resnick\'s figure dovetails with a new report from market research firm Infonetics Research, which found the WiMAX equipment market grew 49 percent year over year in the first quarter of 2011. Part of that growth is attributable to the expansion of existing networks and another part has to do with the technology\'s acceptance in the utility and smart-grid segment, the firm said.

While WiMAX technology has now reached maturity, it\'s clear that LTE technology will offer greater economies of scale down the road for WiMAX operators. The sheer number of vendors and operators embracing LTE is propelling a growing number of WiMAX carriers to make the switch to LTE--Russian carrier Yota is currently switching from WiMAX to LTE, and Clearwire executives have said they expect to make the jump sometime in the future.

Thus, the question for many WiMAX carriers now becomes when and how to make the switch to LTE.

Packet One Networks goes from WiMAX to TD-LTE

Malaysia\'s Packet One Networks Sdn Bhd may be a model for how WiMAX operators might make the transition to LTE. The operator plans to launch a pilot commercial TD-LTE network by year end and introduce full TD-LTE commercial service to its WiMAX network when TD-LTE devices reach maturity, likely in the second half of 2012, said Packet One CEO Michael Lai in an interview with FierceBroadbandWireless. P1 is banking on mobile giant China Mobile and operators in India to drive the TD-LTE ecosystem, and it also hopes to capitalize on the growth of Voice over LTE (VoLTE).

The interesting piece of P1\'s plan, however, is its plan to use WiMAX to continue its DSL alternative play and TD-LTE to offer a mobile broadband service. That means P1 does\'t have to replace any WiMAX devices but just add mobile TD-LTE devices. The operator serves about 300,000 fixed WiMAX subscribers and covers 45 percent of Malaysia\'s population, and has been installing base stations capable of moving to TD-LTE via a software upgrade.

"The ecosystem for WiMAX is still limited. You pretty much have HTC and Samsung for smartphones," Lai said. "We believe by the second half of next year, the small-screen handset with be much more mature with a price point that is affordable for emerging economies like Malaysia."

Already, P1\'s current vendor, China\'s ZTE, has successfully demonstrated on P1\'s network the ability for WiMAX and TD-LTE to co-exist. During the demonstration, ZTE said it used the same WiMAX system to upgrade it to a TD-LTE system in less than an hour, without replacing any hardware. During this process, two terminals shared 20 MHz of bandwidth, with peak TD-LTE speeds reaching 130 Mbps.

To operate both networks, P1 plans to continue operating WiMAX in its 30 megahertz of spectrum in the 2.3 GHz band and add TD-LTE in the 20 megahertz it holds in the 2.6 GHz band. Eventually, the entire network will be based on TD-LTE, and the operator will continue to offer both fixed and mobile broadband services, Lai said.P1\'s major shareholders, SK Telecom and Green Packet Berhad, last month invested another $66.8 million to accelerate its network plans.

It\'s likely that many WiMAX-to-LTE network transitions could play out this way by using disparate spectrum holdings. "Operators can use multiple technology--2.3 GHz with WiMAX and 2.5 for LTE, for example," said Alvario\'s Shakouri. "There\'s no reason these different types of networks ca\'t be designed. At this moment, people are deploying WiMAX because the ecosystem exists."

This will be especially true for those operators that hold spectrum bands that may never support TD-LTE. The 3.5 GHz band is likely to be one of those spectrum bands, Shakouri said. In fact, the vast majority of WiMAX deployments to date have occurred in the 3.5 GHz band.

On the device side, WiMAX operators moving to LTE have a number of options.

"WiMAX operators need to ensure service continuity to avoid churn. They also need to make sure that subscribers\' terminal devices (either desktop modems, dongles or phones) support the right interfaces-WiMAX today, WiMAX and LTE during the transition period, and eventually LTE only. This is particularly important for mobile devices which connect to the network at multiple locations, where different interfaces are available," wrote Monica Paolini, the founder and president of Senza Fili Consulting and a FierceBroadbandWireless contributor. "The alternative is to use multimode devices that support both WiMAX and LTE, which can be introduced in the market organically ahead of the LTE rollout. When LTE becomes available, the new devices see the new network and connect to it, without requiring a hard swap. From a subscriber-and a subscriber support-perspective, multimode devices can simplify the transition process."