South Korea Telecom, one of the first operators worldwide to launch voice over LTE (VoLTE) services, had more than 4.5 million active users of the technology at the end of May.
Dr J W Byun, CTO of SK Telecom, revealed the figure during his keynote presentation at the LTE World Summit taking place in Amsterdam this week. SKT launched VoLTE under the ‘HD Voice’ brand in August of 2012 as it sought to cut ties with legacy voice networks as well as better compete with over the top VoIP services.
Byun reiterated his claim that VoLTE dramatically improves audio quality, relying on high quality audio codecs that are able to handle 2.2 times wider frequency bandwidth as 3G voice. He also made much of improved call setup time which ranges from 0.25 to 2.5 seconds on LTE, compared with a five second setup time on 3G
Rival South Korean operator LG U+ has since introduced VoLTE services too, and Byun was quick to confirm that, since introducing LTE and its associated services, all operators in South Korea have seen an increase in ARPU, especially LG U+.
SKT has nonetheless successfully defended its dominant market position but Byun acknowledged that, with the same network equipment available to all carriers, it is increasingly difficult to find ways of differentiating offerings.
What occupies his time at the moment is developing a “dynamic scheduler” which gives SKT better traffic management capabilities, the CTO said. With data, voice and multimedia all travelling over LTE networks in such large quantities, management of the traffic is now of the utmost importance.