After ESA and several European partners showed in a feasibility study that building a satellite-based phone network is not just technically possible but also quite affordable, recent tests have confirmed this. A test link to a satellite with standardized 5G tech remained stable while it was visible from the receiver's location. This is impressive for two main reasons.
Satellite Specifications
The LEO 3 satellite, launched into low earth orbit specifically for research demo purposes, orbits just below 1,000 km from the Earth's surface. Considering the often angled path (as the satellite moves away from the receiver), the distance can reach 2,000 km or more, which presents challenges for antenna technology.
Speed Challenges
Another aspect is that to stay in orbit, the satellite must move at around 28,000 km/h. This speed makes it quite challenging to maintain 5G coverage throughout the entire visible area of its orbit.
Earlier tests were only done with geostationary satellites that maintain a consistent position above the Earth. However, 5G or any connection with minimal latency can’t be effectively achieved this way. These satellites are positioned at an altitude of 36,000 km, and when factoring in angle, it quickly adds up to over 50,000 km. For this distance, even light takes nearly a third of a second to travel, which is too long for real-time uses.
Future Developments
After the successful initial test, real-time applications seem possible now, partly because a stable connection was made on a regular frequency band using well-established technology. ESA noted that the standards set by 3GPP, a mobile communications standardization committee, were adhered to.
This development opens the door for mobile communications that do not require extra ground-based tech, marking a significant advancement for hard-to-reach areas, crisis zones, and secure communication channels. ESA has already plans for extensive practical testing in 2025.
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