T-Mobile launches VoLTE in Seattle, promises more markets this year

T-Mobile US (NYSE:TMUS) said it has launched Voice over LTE in the Seattle area for customers using three devices, the LG Electronics G Flex and Samsung Electronics Galaxy Note 3 and Galaxy Light. The announcement comes just ahead of AT&T Mobility's (NYSE: T) own VoLTE launch, scheduled for Friday in a handful of markets on one phone.

In a company blog post, T-Mobile CTO Neville Ray wrote that customers using VoLTE will see call setups almost twice as fast as a non-VoLTE call setup. He also wrote that HD Voice service is also included with VoLTE, but noted that T-Mobile has been offering nationwide W-AMR-powered HD Voice on its HSPA network since January 2013.

As with other VoLTE deployments, voice traffic will go over IP instead of the circuit-switched voice network. T-Mobile is also using Enhanced Single Radio Voice Call Continuity (eSRVCC), a new LTE Advanced function that Ray said T-Mobile will be the first to deploy in the U.S. Ray wrote that this is designed to ensure customers won't drop a call if they leave an LTE area and the call switches to HSPA+ or 2G coverage. T-Mobile's LTE network currently covers 210 million POPs, and the company has previously said it plans to increase that to 230 million by mid-year and 250 million by the end of 2014.

Ray wrote that T-Mobile plans to roll out VoLTE "to more T-Mobile customers throughout the coming year" but did not provide a timeframe for doing so. A T-Mobile spokesman did not immediately respond to a request for comment on the topic.

Ray also wrote that launching VoLTE is T-Mobile's "first step toward a host of rich communication services and additional innovations around Wi-Fi calling that we're looking to deliver to our customers over the coming months." He added that T-Mobile's engineering team "is working tirelessly" to launch VoLTE in additional cities and with more devices.

Verizon Wireless (NYSE: VZ) reiterated this week that it plans to launch VoLTE sometime this year, and said that when it launches the service the carrier will offer a "robust line" of VoLTE-capable smartphones and video calling services. Verizon has not set a specific timeframe for the launch but has said the service will be available nationwide--meaning, Verizon does not plan to roll out the service on a market-by-market basis. HD Voice and video calling are going to be the two main services initially offered through VoLTE technology, and will be accessible through a phone's native dialer.

AT&T last week announced it would launch VoLTE services this Friday via the Samsung Galaxy S4 mini in select areas in Illinois, Indiana, Minnesota and Wisconsin. The carrier said it will expand to additional markets and phones in the future. AT&T said the technology would power HD Voice functions but made no mention of video calling.

Sprint (NYSE: S), for its part, has said it is in no rush to launch VoLTE. The company will rely on its CDMA network and EVRC-NW-powered HD Voice technology for voice calling services for the foreseeable future, Sprint Chief Network Officer John Saw told FierceWireless in March. Saw said Sprint is investing in VoLTE technology, but doesn't have a timeline for deploying the service. Sprint has said its HD Voice calling service will be available nationwide by the middle of this year.

For more:
- see this T-Mobile blog post

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