South Korea number-one SK Telecom has announced it will commercially roll-out multi-carrier technology for its LTE services in July, following a world-first pilot in Seoul.

The multi-carrier technology uses both 800MHz and 1800MHz frequency bands to double the bandwidth used for LTE, boosting speed and quality of service. SK acquired a 20MHz chunk of 1800MHz spectrum in 2011, meaning it has a total of 40MHz for its LTE service.

Multi-carrier technology allows for more effective and efficient use of frequencies as it intelligently distributes mobile data traffic to each frequency band to prevent overloading of the networks. SK compares the system to building an additional road in an always-congested area and controlling traffic flow to move more smoothly.

The current pilot of the technology is taking place between Gangnam Station and Kyobo Tower Crossroads in Seoul. The operator plans to cover the whole Seoul area by the end of 2012 and add 23 other major cities in early 2013. When rolled out commercially, the service will be twice as fast as any other LTE network in South Korea, the firm claims.

The use of the 1800MHz frequency will also allow SK to offer LTE roaming services with around ten countries in Asia and Europe having chosen the frequency for their LTE services, with more expected to follow suit.

SK is working with device manufacturers to incorporate multi-carrier technology into LTE smartphones launched on its network from the second half of the year. The technology is currently only featured in the Pantech Vega Racer 2 smartphone, launched in May 2012.