"The current terrestrial network consolidates only 14% of Earth's surface with mobile networks. The remaining roughly 85% gap will be filled by a space-based satellite network built on 6G." (Lee Moon-gyu, professor, School of Electrical, Electronic and Computer Engineering, University of Seoul)
"As a latecomer in satellites, Korea's shortcut to competitiveness is to expand artificial intelligence (AI) services of terrestrial networks into space." (Choi Ji-hwan, professor of aerospace engineering, KAIST)
The Korean Academy of Science and Technology (KAST) on the 23rd held the 248th KAST Roundtable at The Plaza Hotel in Jung-gu, Seoul, under the theme "Mobile communications in the Starlink era: Korea's response strategy toward the era of satellite–terrestrial network coexistence." With the recent spread of low Earth orbit satellite communication services represented by SpaceX's Starlink, the mobile communication environment is shifting to a satellite–terrestrial network coexistence system. At the forum, experts actively discussed Korea's response strategy to the global shift in the communications paradigm.
Lee Moon-gyu, professor at the University of Seoul's School of Electrical, Electronic and Computer Engineering, presented on "The technical reality of Direct-to-Cell (smartphones communicating directly with satellites) and non-terrestrial networks (NTN): what is possible and what is still difficult." Lee said, "SpaceX's Starlink is putting 15,000 base stations into space via a direct-to-cell approach, and some worry that Starlink could monopolize the global direct-to-cell market," adding, "But that concern is overstated."
Lee said, "The direct-to-cell approach allows for a strategic approach akin to 'roaming,' in which users in areas outside existing networks use facilities of satellite operators," adding, "In the end, non-terrestrial networks will serve at the level of a supplement to mobile networks, leading satellite operators and terrestrial carriers to maintain a cooperative relationship."
Choi Ji-hwan, professor of aerospace engineering at KAIST, presented on "Korea's options: future countermeasures for satellite–terrestrial network coexistence," saying, "As a latecomer, Korea needs a strategy that leverages external satellite networks. We must focus on extending all core terrestrial technologies—AI, semiconductors, Edge Computing, data centers, and power grids—into space."
In Korea last year, KT and SK Telink entered the B2B (business-to-business) domain, and Starlink Korea launched official service for individual users. The United States, centered on Starlink, has completed a privately led space economy model, while Europe is pursuing a dual-track strategy of building its own satellite networks and leveraging Starlink. In Japan, SoftBank and Starlink are used in the B2B domain, and for general individual users, in addition to Starlink, domestic operators Rakuten and NTT offer direct-to-cell services. China, led by the state, has deployed 13,000 satellites to build space infrastructure to counter the United States.
Kim Seung-jo, emeritus professor of aerospace engineering at Seoul National University, also presented on "The status of the Starlink system and beyond," emphasizing, "For Korea to realize a space economy, existing large industrial sectors must converge with space technology to create a new, large market."
Kim said, "Satellite communications centered on low Earth orbit will capture the world," adding, "The key is solving power and cooling in space, and the crux is how to deal with radiation." He added, "In the space economy, Korea should respond by leveraging AI technology."
◇ "In the Starlink era, the game is not 'launch speed' but 'standards and ecosystem'"
In the discussion that followed the presentations, participants examined not only the opportunities that low Earth orbit satellite communications will bring, but also the technical, standards, and business hurdles that must be cleared to stably realize it as a commercial service. Experts agreed that in the era of satellite–terrestrial network coexistence, the key is not only "who can launch satellites faster," but also to preempt standards, secure essential technologies, and build the ecosystem starting with markets and services advantageous to Korea.
Shim Byung-hyo, professor at Seoul National University's Department of Electrical and Computer Engineering, noted that satellite communications inherently face clear technical challenges because they occur over distances of hundreds of kilometers or more. Shim said, "It is difficult to ensure communication quality due to path loss, where signals weaken as distance increases, and even though radio waves travel at the speed of light, the sheer distance causes latency," adding, "Also, because satellites move quickly, handover technology—seamlessly passing on the consolidation without drops as the counterpart keeps changing—is crucial." He emphasized that to solve this, high-performance antennas and advances in satellite power and antenna design must progress together.
In particular, Shim said that as inter-satellite links—direct consolidation between satellites to relay data mid-route—become more widespread, inter-satellite routing (technology that determines the optimal path for data) that reduces inefficient detours will grow in importance. Shim said, "The later you enter, the more critical your technological competitiveness is from a network perspective," adding, "In the direct-to-cell approach where smartphones communicate directly with satellites, the limits of phone battery and antenna size ultimately shift the burden to satellites. Satellite power output and antenna requirements will inevitably surge."
Lee Moon-sik, head of the Satellite Communications Research Division at the Electronics and Telecommunications Research Institute (ETRI), proposed Korea's response from the perspective that standards equal competitiveness. Lee said, "As NTN standardization is gaining momentum around the global mobile communications standards body 3GPP, Korea must secure leadership," adding, "If standard-based capabilities are accumulated, the domestic industrial ecosystem can expand globally."
Lee added, "Future axes of competition include AI-based intelligent satellite communications, services that combine communications with precision positioning, navigation and timing (PNT), and the integration of sensing and communications," adding, "If systems are built on standards, satellite sharing and international cooperation between countries and institutions become easier, and export opportunities open."
From a carrier's perspective, Lee Jong-sik, head of KT's Future Network Research Institute, said, "Starlink has moved toward commercialization with satellite internet and direct-to-cell at the forefront, but considering actual perceived speeds, capacity, and price burdens, the immediate impact to shake the market is limited," adding, "For satellite networks to have a big impact, the expense must come down further."
Lee added, "It is not easy to build an independent satellite network and turn a profit on private demand alone," adding, "We need to find additional revenue sources, such as data centers, added functions on board, and supplementing submarine cables, where expansion burdens are growing due to increases in AI data."