SK Telecom, South Korea’s largest mobile operator, has demonstrated download speeds of up to 225Mb/s using LTE-Advanced technology.

Carrier aggregation (CA) techniques were deployed in the demo, pooling together 20MHz in the 1.8GHz frequency band and 10MHz at 800MHz.

SK Telecom says it expects to launch the faster service commercially in the second half of 2014, once compatible smartphone chipsets are available. Such efforts would, claim the operator, enable customers to download an 800MB movie in just 28 seconds. “Measured at their maximum speeds, downloading the same movie file via 3G, LTE, and the existing LTE-Advanced (10MHz+10MHz) would take 7 minutes and 24 seconds, 1 minute and 25 seconds, and 43 seconds, respectively,” noted the operator in a statement.

Local rival KT also has similar plans for a 225Mb/s LTE-Advanced service using the 1.8GHz and 900MHz bands.

Plain LTE can ‘only’ offer theoretical peak download speeds of up to 150Mb/s using a maximum of 20MHz of continuous spectrum in one band (although this speed is highly unlikely to ever be achieved in real world conditions). LTE-Advanced technology can support theoretical peak speeds over 150 Mb/s by combining different bands through CA.

The South Korean operator launched the world’s first commercial CA-based LTE Advanced network in June 2013, combining 10MHz bandwidth of 1.8GHz frequencies and 10MHz in the 800MHz band.

The LTE-Advanced service from SK Telecom has proven popular, attracting more than one million subscribers in less than four months after launch.

SK Telecom’s hand has been strengthened by the allocation of additional spectrum. On 30 August, the operator got the green light to use a 35 MHz chunk of 1.8GHz bandwidth (20MHx downlink + 15Mhz uplink). It has used the extra bandwidth to bolster both its LTE and LTE-Advanced services.

The operator says it now has plans to aggregate three carriers (20MHz+10MHz+10MHz) to support up to 300Mb/s of speed, although timetables are not yet clear.

South Korea is a hotbed of LTE and LTE-A activity. According to a GSMA Intelligence study, half of total mobile connections in the country had migrated to LTE as of November 2013 – compared to a 20 per cent average in Japan and the US – making South Korea the most advanced LTE market worldwide.

SK Telecom’s headline grabbing speed announcements may be an attempt to take some of the shine off UK operator EE’s launch earlier this month of what it claimed is “the fastest 4G mobile network in the world”, which it said can reach speeds of 300Mb/s – although it is still some way from a commercial launch.