SK Telecom Commercializes: Five-band Carrier Aggregation and 4X4 MIMO

SK Telecom has commercialized five-band Carrier Aggregation (CA)* and 4X4 MIMO, which are key technologies of LTE-A Pro, the last stage of LTE evolution.

SK Telecom's bandwidth resources as of February 2017: 10MHz bandwidth in the 800MHz band, 20MHz bandwidth in the 1.8GHz band, 10MHz bandwidth in the 2.1GHz band, 10MHz + 20 MHz bandwidths in the 2.6Ghz band.

Five-band CA is a core LTE-A Pro technology that enhances data transmission speed and performance by aggregating five component carriers. SK Telecom’s five-band CA LTE-A Pro service supports up to 700Mbps data rates, enabling users to download an HD movie (2GB) within 23 seconds. The five-band CA LTE-A Pro service currently covers 53 cities in Korea, including Seoul, Busan and Daegu.

Moreover, today, the company has launched the 900Mbps LTE-A Pro service by combining three-band/ four-band CA and 4X4 MIMO. The 900Mbps LTE-A Pro service currently covers main areas of six major cities namely Seoul, Busan, Daegu, Gwangju, Daejeon and Ulsan.

Samsung Galaxy S8 users will be able to enjoy these LTE-A Pro services via an over-the-air firmware upgrade. The company projects that the to-be-launched premium smartphones will support LTE-A Pro services.

Going forward, SK Telecom plans to aggressively expand the coverage of its LTE-A Pro services: It expects that the five-band CA LTE-A Pro service and 900Mbps LTE-A Pro service, when combined, will cover more than 50 percent of the Korean population by the end of this year.

With the commercialization of key LTE-A Pro technologies, SK Telecom is well-positioned to further solidify its leadership in the marketplace. By combining five-band CA or four-band CA with other key LTE-A Pro technologies like 4X4 MIMO, SK Telecom plans to launch 1 Gbps LTE-A Pro service in the first half of 2018. To this end, the company is applying key LTE-A Pro technologies, including five-band CA, 4X4 MIMO, and 256 QAM*, to its base stations nationwide.

SK Telecom has opened the 4.5G era in June 1, 2016 by applying the 256QAM technology to its tri-band LTE-A CA network, which supports peak data rates of 500Mbps. At present, the service is available in main areas of all 85 cities in Korea, covering approximately 51 percent of the Korean population.

“SK Telecom’s LTE-A Pro services represent an early application of 5G technologies that support Gbps-level data speeds and massive network capacity. 4.5G can be considered as the very last stage of LTE and will facilitate the spread of immersive multimedia services, including virtual reality (VR), augmented reality (AR) and 3D hologram content,” said Choi, Seung-won, Senior Vice President and Head of Infrastructure Strategy Office. “SK Telecom will continue to offer differentiated mobile communications quality through LTE-A Pro service, while utilizing the network to gain a valuable edge in the 5G era.”