Earth’s orbit will soon be teeming with new satellites. Companies such as Amazon and Space X want to use them to connect even the remotest corners of the globe to the Internet. Researchers from the Swiss Federal Institute of Technology (ETH) in Zurich recently unveiled how this Internet from space could be optimized even further.
Space X plans to start offering satellite-based broadband Internet as soon as next year. Amazon and One Web have also launched fleets consisting of thousands of small, low-orbit satellites that will provide Internet access and high-speed data communications to remote areas.
Researchers led by Ankit Singla from ETH Zurich are investigating how the performance of such large networks could be improved.
According to the researchers, Internet from space is creating completely new premises. Because unlike the Internet infrastructure on the ground, the infrastructure in orbit is not static. The satellites represent nodes that constantly change their relative positions. “In order to implement satellite-based broadband Internet, we have to rethink practically every aspect of conventional Internet design,” Ankit Singla explains.
With her team, she has developed a mathematical model that allows the design of satellite-based networks to be optimized. The researchers report that they tested their approach using the infrastructures of Space X and Amazon. They were able to increase their satellite network efficiency by 54 and 45 percent respectively. Their approach could also be applied to other satellite networks.
The principle is based on
reducing the number of nodes – i.e. satellites – through which the data is
transmitted. This frees up resources that can then be used for other
connections. In concrete terms, this means that a satellite should not
necessarily transmit the data to the satellite that is closest it, but could
well connect to a more distant one, thus spanning greater distances.
This reduction of the intermediary nodes must not, however, compromise the length of the end-to-end path, according to the ETH researchers. Otherwise, the latency, i.e. the delay in the data transmission, would increase. In addition, it is important that the connections between the satellites are not adjusted too frequently, because each new connection can take several dozen seconds to establish. During this period, no data is transmitted.
What makes the network
design so innovative is that the connections between the satellites are
established according to a recurring pattern: The connection pattern is
replicated in each satellite in the network, so that they are all connected in
an identical way and the connections remain stable over time, even when the
satellites move. Which pattern is most suitable depends, among other things, on
the geometry of the satellite constellation.
Written by SDA
Photos by SDA-KEYSTONE