Tuesday, August 7, 2012

SK Telecom Launches HD Voice over LTE


SK Telecom launched an HD VoLTE service, initially featuring the Samsung Galaxy S3 LTE handset. Customers who already have the handset will be able to download a firmware upgrade later this month. The Galaxy Note 2 will also offer an HD VoLTE capability.
  • The premium HD voice service is available at no additional charge.
  • The HD voice connection uses 2.2 times the bandwidth of voice over 3G.
  • The HD voice call connection time ranges from less than 0.25 to 2.5 seconds. This compares with a mean call connection time of 5 seconds for 3G voice calls, and SK Telecom believes this difference will be apparent to the customer.
  • HD VoLTE carries a wide voice frequency range of 50 to 7000 hertz compared to a 3G voice call that typically covers 300 to 2400 hertz. The service uses Enhanced Variable Rate Codec (EVRC).
  • SK Telecom is using multi-carrier technology for the 800 MHz (20MHz) and 1.8 GHz (20MHz) frequency bands.

  • Last month, SK Telecom announced plans to commercialize LTE-Advanced in its network during 2013.

    SK Telecom, in collaboration with Qualcomm and Nokia Siemens Networks, recently tested a core LTE-Advanced technology called 'Enhanced Inter-Cell Interference Coordination (eICIC) that coordinates signal interference between macro and pico base stations. eICIC is gaining importance as more and more micro base stations are being built in traffic concentrated areas to accommodate explosive data traffic growth, thereby aggravating inter-cell interference.

    To demonstrate the technology, SK Telecom, Nokia Siemens Networks and Qualcomm created an environment where the strength of micro base station signals being transmitted to mobile devices was weaker than that of nearby macro base signals, resulting in signal interference. Then, they applied eICIC to prove that it can actually control the interference and stabilize data communications.

    The companies also succeeded in showing that the technology is capable of offloading data traffic by adjusting the coverage of micro base stations based on the level of data traffic concentration in macro and micro base stations. As commercial base station equipment has been used for the demonstration, the companies are expecting to achieve early commercialization of eICIC.

    SK Telecom noted that it now holds the record of demonstrating the three core technologies needed to usher in the era of LTE-Advanced: eICIC, Coordinated Multi-Point (CoMP) and Carrier Aggregation (CA). The company successfully demonstrated CoMP at Mobile World Congress (MWC) 2011 and CA at MWC 2012.

    CoMP is a technology that prevents base station interference and abrupt call disconnections in coverage boundary areas by enhancing signal strength, the lack of which leads to a significant drop in data transmission speed, and CA is a technology that provides twice or faster data rates by utilizing multiple frequency bands at the same time.

    SK Telecom expects to commercialize eICIC in the second half of 2013 to control signal interference and effectively offload data in downtown areas that experience heavy data traffic so as to provide customers with a mobile data service with greater speed and stability.

    The company commercialized CoMP, for the first time in the world, in January 2012, after adjusting the technology to suit the current LTE system, and plans to achieve early commercialization of CA in the second half of 2013.

    The operator will deliver LTE using both existing 800MHz frequency band (20MHz) and the 1.8GHz band (20MHz) it newly acquired last year. With an additional 20MHz uplink/downlink spectrum, it is now using a total of 40MHz for its LTE services. SK Telecom has launched a pilot service for multi-carrier in May 2012 and began full-fledged commercialization on July 1 to ensure a more stable and faster LTE service based on twice wider frequency bandwidth than its competitors. CA realizes data rates of up to 150Mbps by combining the speeds of 800MHz (75Mbps) and 1.8GHz (75Mbps) frequency bands.
  • In June, SK Telecom commercialized world's first LTE Femtocell to provide stable LTE call quality in underground, buildings and data traffic concentrated areas. With LTE Femtocell, customers can use high speed, premium quality LTE services anywhere, anytime.
  • In May 2012, Ericsson announced that SK Telecom, South Korea's largest operator, had signed a contract for LG-Ericsson to provide the LTE network including LTE RAN and Evolved Packet Core as well as support services including engineering, design, deployment and support services. The LTE radio access network will make use of Ericsson's Operation Support System for Radio & Core (OSS-RC) and RBS 6000 base stations. The contract, which covers commercial launch of LTE services in some of Korea's major cities - including Busan and Daegu, makes Ericsson one of the operator's main partners. Financial terms were not disclosed.
  • In January 2012, SK Telecom achieved the world's first commercialization of Advanced-SCAN (Smart Cloud Access Network), an upgraded version of SCAN, which has been developed to enhance LTE speed and coverage. Advanced-SCAN uses virtualization technology to ensure four times better call quality in base station boundary areas, thereby improving the overall LTE coverage and speed.