As communication technology continues to evolve, the effort to broaden the reach of communication networks has been relentless. In the upcoming 6G era, network coverage is expected to expand beyond the constraints of the Earth’s surface and into the three-dimensional aerospace domain. Preparing for this, KT has successfully developed a technology that integrates 5G NTN with satellites operated by KT SAT.

On September 30, KT Corporation (CEO Kim Young-seob) and KT SAT (CEO Seo Young-su) announced their successful integration of terrestrial 5G networks with the Mugunghwa Satellite 6 (KOREASAT 6), positioned 35,800 km above Earth in geostationary orbit (GEO). This groundbreaking achievement marks the first instance of applying the 5G Non-Terrestrial Network (NTN) standard to a GEO satellite. The collaboration involved key partners, including Rohde & Schwarz Korea and Viavi Solutions Korea, with tests conducted at KT SAT’s Geumsan Satellite Center.

5G NTN: Revolutionizing Network Expansion

5G NTN technology is a pivotal standard that extends 5G service coverage by leveraging satellites instead of ground-based stations. This standard was defined in 3GPP Release 17, finalized in 2022. While NTN networks offer lower data transmission speeds than terrestrial 5G, they fill coverage gaps in remote areas, such as seas, mountains, and airborne regions. By seamlessly connecting 5G NTN and traditional 5G networks, users can enjoy uninterrupted service.

One of the core challenges of satellite communication is managing the propagation delay caused by long distances and compensating for frequency shifts due to satellite movement (the Doppler effect). During the recent tests, KT successfully addressed these issues, applying precise corrections to account for the 35,800 km distance between the satellite and Earth.

A New Frontier in Communication

KT emphasized that 5G NTN could revolutionize the telecom industry, connecting billions of people and devices across the globe. With this technology, business opportunities abound, and coverage can extend to previously unreachable locations.

The company also noted that the standardization work for 5G NTN to partly replace terrestrial 5G networks is already underway within 3GPP Release 19. Once these standards are finalized, KT will conduct further tests to verify its capabilities.

KT’s plans also include expanding NTN technology to various aerospace communication platforms, such as Medium-Earth Orbit (MEO) satellites, Low-Earth Orbit (LEO) satellites, and High Altitude Platform Stations (HAPS), ensuring comprehensive coverage in the sky and beyond.

Partners Speak on the Significance of 5G NTN

Rohde & Schwarz Korea’s CEO, Kim Tae-hoon, highlighted the importance of NTN as a core technology for 5G and future 6G networks. “By utilizing satellites, NTN technology expands the coverage of terrestrial communication networks into diverse areas such as maritime and airborne regions,” Kim stated.

Similarly, Viavi Solutions Korea’s Managing Director, Seo Beom-seok, expressed excitement over the successful collaboration. He noted that validating the technology through GEO satellites opens the door for 5G NTN services in LEO as well and positions NTN as a critical enabler of the ultra-broadband, hyper-connected, and low-latency services that 6G will pursue in the long term.

The Path to 6G

KT’s Network Research Director, Lee Jong-sik, emphasized that the NTN technology, first introduced in the 5G Advanced standard, will be central to 6G’s development. “In the 6G era, coverage will expand beyond the Earth’s surface into three-dimensional aerospace realms, ushering in a true era of ubiquitous communication.”

With this groundbreaking achievement, KT and KT SAT have set the stage for a new age of global communication, paving the way for the limitless potential of the 6G era.