Clearwire's new 4G handsets may have a VoIP twist

As Clearwire (NASDAQ:CLWR) gears up to offer its first WiMax handsets later this year, it finds itself in unique position among wireless operators. It has no legacy voice service or network to maintain and thus has a clean slate to offer the first U.S. mobile voice service based entirely on voice over IP.

Chief commercial officer Mike Sievert said Clearwire is definitely investigating offering voice as an another IP service over its 4G WiMax network, and as Clearwire’s footprint grows it could eventually become the dominant voice service on its network, obviating the need for a CDMA 1X connection that will be standard in its initial handsets. But Sievert said if such a VoIP service does happen it will be further down road. At launch, Clearwire will most likely rely on Sprint (NYSE:S) or other network-sharing partners for their CDMA connections, he said.

“Mobile VoIP is definitely something we’re very interested in, but we won’t default to VoIP when we first launch,” Sievert said. Clearwire, however, plans to work closely with third-party VoIP providers to support their voice services on their network. Many of Clearwire’s customers already use VoIP services over the WiMax networks, using clients in their laptops or other devices connected to the 4G network through a Wi-Fi router. Sievert plans to extend that flexibility to handsets. At least one of the two, Samsung’s multimedia handset, will use the Android operating system, which already has several VoIP applications available to it. The higher bandwidths and lower latencies of the WiMax network will only ensure a better voice experience over those clients — much more consistent than a 3G network, Sievert added.

While supporting all VoIP, Sievert drew the line at the prospect of Clearwire partnering with a VoIP provider like Skype to become the "official" or integrated VoIP provider for the Clear service. “When you press ‘send’ the call will route to the cellular network,” Sievert said.

Clearwire still has a ways to go before it can offer a nationwide VoIP-over-4G service. Though in the middle of a large-scale WiMax rollout targeting 120 million pops covered by year end, Clearwire will still only have one-third of the population blanked with 4G by the time its handsets go on sale. If Clearwire is to offer nationwide and voice and data plans to its handset subscribers, it will have to rely heavily on partners to fill in its 4G holes — for both voice and data. Luckily for Clearwire, it has an ideal partner lined up. Not only is primary investor Sprint wholesaling CDMA 1X and EV-DO network access to Clearwire, just as the former buys 4G access from the latter, Sprint is spurring its vendors to build dual-mode CDMA-WiMax devices, an ecosystem Clearwire can tap into for its own 3G-4G service.