In particular, voice over LTE (VoLTE) calling is often touted by carriers as offering increased reliability and better sound quality.

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The carrier says it will commercially launch the service, known as Voice over LTE or VoLTE, in 2012, in part to improve call quality for its customers.

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Replacing traditional voice service with voice over LTE will take time, as complex kinks are worked out, network equipment is installed and, eventually, phones are made with the necessary hardware.

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