As communication technology evolves, efforts to expand the areas where communication is possible have continued. In the 6G era, communication coverage is expected to expand beyond terrestrial limitations to the three-dimensional aerial domain. In preparation for this, KT has secured the technology to link KT SAT’s satellite with 5G NTN.

 KT (CEO Kim Young-seop) and KT SAT (CEO Seo Young-soo) announced on the 30th that they have succeeded in securing the technology to link the terrestrial 5G network and KOREASAT 6, located at an orbital altitude of 35,800 km, with their satellite communication partners using the 5G NTN (Non-Terrestrial Network) standard.

 This is the world’s first case of the 5G NTN standard being applied to a geostationary Earth Orbit (GEO) satellite. The test was conducted at KT SAT’s Kumsan Satellite Center in collaboration with KT, KT SAT, Rohde & Schwarz Korea, and VIAVI Solutions Korea.

 5G NTN is a standard technology that drastically expands the 5G service range by utilizing satellites instead of ground-based base stations. This technology was defined in 3GPP (3rd Generation Partnership Project) Release 17 (Release 17 means the 17th mobile communication standard developed by 3GPP) and was completed in 2022.

 Using 5G NTN, data transmission speeds are slower than terrestrial 5G networks, but services are provided in areas with coverage gaps such as sea, air, and mountainous areas. By utilizing the characteristics of easy connection between existing 5G networks and 5G NTN coverage, uninterrupted services can be provided to customers. The

 core technology of satellite communication is to precisely process the propagation delay caused by long distances and the frequency change (Doppler effort) caused by the movement of the satellite. During this test process, KT implemented a technology that accurately compensates for the long delay time over a distance of approximately 35,800 km using 5G NTN technology.

 KT explained that 5G NTN is a technology that can bring about new changes to the communications industry, and that 5G NTN is necessary to connect and protect billions of people and objects, as well as business opportunities.

 Meanwhile, KT stated that standards work on technologies for 5G NTN to partially replace terrestrial 5G networks is in progress in 3GPP Release 19, and that it will begin verifying the technology through interoperability tests as soon as the standards are completed.

 In addition to the geostationary satellites used in the process of securing this technology, KT plans to secure NTN technology that is interoperable with various aerospace communication platforms such as medium-Earth Orbit (MEO) satellites, low-Earth Orbit (LEO) satellites, and high-altitude platform stations (HAPS) supported by the 3GPP 5G NTN standard.

 Kim Tae-hoon, CEO of Rohde & Schwarz Korea, said, “NTN is one of the core technologies of 5G and future 6G, and is a technology that utilizes satellites to expand terrestrial communication networks to various spaces such as the sea and the air. “We are very pleased that Rohde & Schwarz Korea’s expertise and innovation were able to join us in this technology verification that was conducted to ensure the smooth operation and user experience of the 3GPP standard-based NTN service,” he said.

 “First of all, we are very pleased that Viavi Solutions Korea can participate in KT’s 5G NTN project,” said Seo Beom-seok, CEO of Viavi Solutions Korea. “This technology verification of 5G NTN using GEO satellites will not only explore the possibility of low-orbit 5G NTN services in the short term, but also enable the provision of broadband, hyper-connectivity, and low-latency services pursued in 6G in the long term through NTN technology.”

 Lee Jong-sik, managing director and head of KT’s Network Research Institute, said, “NTN technology, which began to be defined in the 5G Advanced standard, will become a core technology of 6G in the future,” and “In the 6G era, communication coverage will expand beyond terrestrial limitations to the three-dimensional aerial domain, opening up a truly ubiquitous communications era.”