The proof of concept successfully transferred a live session from a commercial geostationary Earth orbit satellite to an emulated low Earth orbit environment in a lab
In sum — what to know:
PoC of multi-orbit mobility: In a joint trial, Keysight and KT SAT successfully demoed a handover between a geostationary Earth orbit (GEO) satellite and an emulated low Earth orbit (LEO) satellite link.
The test kit: The experiment used Keysight’s Network Emulator Solutions and UeSIM RAN Testing Toolset, and was carried out over a live Ku‑band connection in a controlled lab environment.
A path for continuous connectivity: As the industry moves towards 6G at full speed, the PoC seeks to give operators a way to evolve from point-to-point satellite links and achieve resilient always-on coverage.
Keysight, in collaboration with Korean satellite service operator KT SAT, has achieved, what it claims to be the “industry’s first” New Radio Non-terrestrial network (NR-NTN) multi-orbit satellite handover — a feat that hints at the possibility of ubiquitous coverage in the future.
The lab-based proof-of-concept (PoC) conducted at KT SAT’s Kumsan Satellite Network Operation Center in Korea, established a live connection and successfully handed over an active session from the operator’s telecom GEO satellite, Koreasat 6A that launched in November 2024, to an emulated LEO satellite link, the companies said.
The trial used Keysight’s Network Emulator Solutions and UeSIM RAN testing toolset for emulating base stations and user equipment — was conducted over a Ku‑band spectrum with downlink and uplink speeds of approximately 12.3 GHz and 14.4 GHz, respectively.
The experiment marks a significant milestone, demonstrating that global coverage might be achievable through convergence of terrestrial and non-terrestrial networks. Specifically, the inclusion of Ku-band is significant, given its role as a core frequency for satellite communication supporting direct-to-home (DTH) broadcasting, satellite internet services, and many military and defense applications.
“Satellite networks, especially LEO constellations, will be a foundational element of 6G,” said Jesse Cavazos, 6G solutions lead at Keysight to RCR Wireless News. “Unlike 5G where NTN was supplemental, 6G envisions NTN as a Day 1 native component of the network architecture. This integration is expected to enable seamless convergence between terrestrial and non-terrestrial networks, supporting unified control, resource management, and service delivery.”
The convergence of conventional and satellite-based infrastructures represents a significant progress towards Internet for All — and in many places, the digital divide is already closing, but the integration comes with steep engineering and operational challenges that the industry has only begun to confront.
One of the biggest barriers is handover (HO) or transferring of a user connection from one satellite or base station to another as they move. The challenge is keeping the active sessions going uninterrupted through the transfer. With the satellites constantly moving, the service beams changing, the process is already exceedingly tricky. Issues like longer propagation delays and Doppler effects further add fuel to the fire.
Keysight and KT Sat’s demonstration seeks to lay out a practical pathway for telecom operators to evolve out of single-orbit links by overcoming the challenges, and achieve resilient always-on coverage in their push toward 6G.
“This achievement validates a core capability for 6G and demonstrates that multi-orbit mobility is no longer theoretical. It provides a practical path for the industry to extend coverage to underserved areas without relying solely on terrestrial infrastructure,” Cavazos said.
And for vendors, it shows how to test NTN behaviors for large-scale deployment in a lab at reduced cost and lower risk. At the very least, it will give KT SAT a way to advance towards a multi-orbit satellite service portfolio.
Today, approximately 12% of the U.S. population live in households without an internet connection, according to an NTIA survey conducted in 2023. The following year, a Federal Communications Commission (FCC) report also found that over a third of Americans has access to only one broadband service or none at all, underscoring the need to intensify efforts to reduce the digital inequality by pushing broadband access deeper into underserved communities.
