Prior to 1964, a geostationary orbit was an idea that existed only in science fiction. A recurring theme across articles and books was the notion of a satellite hovering above the Earth, with which it rotated in unison, in a fixed position above the equator. In 1964, this idea was realised with the first geostationary (GSO) satellite successfully launched. At this point in our world’s history, satellite technology was in its infancy – but the launch allowed for the first live transmission of a major sports event, the Tokyo Olympics.
The geostationary satellites we use today have their uses, but new technology has taken its place in favour of shorter transmission times, wider coverage and lower associated costs. As we look forward to this summer’s version of the Tokyo Olympics, 57 years later, it’s these advancements of technology that will see us be able to watch live, high-definition coverage that’s as if we’re there in the audience alongside fans.
It wasn’t until late in the 1980s that satellites sitting in a non-geostationary orbit became used for communication purposes, as these systems are much more complex. Non-geostationary satellites (or NGSOs) sit at medium Earth orbits – which have an altitude of 8,000-20,000km – and low Earth orbits – which have an altitude of 400-2,000km. These satellites, as the name implies, do not sit in a stationary orbit, but rather they travel across the Earth’s sky continually.
As this technology continues to evolve, the project MegaLEO envisages a satellite constellation that will be able to autonomously execute their own network configurations from space. Born out of a collaboration between SnT’s SIGCOM research group and GomSpace Luxembourg, the project has just received funding from the Luxembourg National Research Fund (FNR) to explore self-organised and self-healing satellite constellations at low Earth orbit. “We are very excited to be working with SnT on this exciting venture. As a global leader in the manufacturing of CubeSats and small satellites, we see the MegaLEO project as the perfect opportunity to combine our resources to design an intelligent constellation,” said Niels Buus, CEO at GomSpace.
One of the project’s primary areas of research will be in matching the diverse traffic demand from across the globe. As it stands, billions of people worldwide don’t have access to broadband internet – affecting mainly people located in remote areas of the planet, or rural plains. Governments universally have insisted that this technological divide will need to be addressed in order to promote economic growth and social inclusion, but it’s a situation that’s easier said than done. Traditionally, getting remote areas connected to the internet provides a low return on investment, since by definition there are few people in the area that will benefit. On the other end of the scale, there are areas that struggle to get high-speed internet connectivity due to the sheer number of people trying to access a network – as is the case if you try to use your phone at a concert or festival.
On SnT’s side, the team working on MegaLEO is being led by Prof. Symeon Chatzinotas, and also includes Dr. Eva Lagunas, Dr. Steven Kisseleff, Dr. Houcine Chougrani and Dr. Hayder Al-Hraishawi. Speaking about the project, Dr. Lagunas said, “Most current satellites distribute capacity uniformly over the coverage area, but it shouldn’t be this way. More resources need to be directed, or focused, towards areas where there is a higher demand. We envision a constellation that is efficient, and can operate intelligently and autonomously.”
“We will design a constellation that will be self-sufficient. It won’t need human interference and should be able to shift its location or frequency on its own in order to offer a more targeted distribution of resources,” she continued. The constellation will consist of smaller sized satellites, which are much cheaper to produce and have a life-span of 1-3 years. Although this may sound like a small amount of time, it allows for the infrastructure to continually evolve as new research comes to light.
As it stands, creating constellations out of NGSO satellites is a relatively new field when it comes to communications. The first systems are currently emerging, most notably SpaceX’s Starlink constellation, which is currently offering internet service to the US, UK, many European countries including Belgium and Germany, as well as New Zealand and Australia. As of May 2021, they have nearly 1,500 satellites currently in orbit, although they have received approval for the launch of around 12,000.
Work on the MegaLEO project will begin in September 2021 for three years. The next stage of the preparations will see them take on board two doctoral candidates, who will dedicate all of their time to the project’s execution.