German Start-up Wins Tender for Innovative Test Satellite

LoLaSat – a small low-flyer (Credit: S4 GmbH)
  • The German Space Agency in the German Aerospace Center (DLR) is committed to promoting start-ups within the framework of the European space organization ESA.
  • On July 5, 2021, the German space start-up was awarded the contract to build and operate an innovative test satellite for broadband internet in very low Earth orbit.
  • The test satellite “LoLaSat” (Low Latency Communication Satellite) is intended, among other things, to significantly shorten the transit times of the signals and pave the way for Internet via satellite, also for virtual reality or augmented reality and certain applications in autonomous driving.

COLOGNE (DLR PR) — Young, innovative companies are playing an increasingly important role in space travel – also in Germany. 

“Start-ups enrich space travel. They bring a breath of fresh air into the industry and drive technological developments. We promote this development and are strongly committed to young companies in the German space travel landscape. We are therefore very pleased that a consortium around the Würzburg Start-up S4 GmbH (Smart Small Satellite Systems) will develop, build and operate the innovative LoLaSat test satellite on behalf of the European Space Agency (ESA) in a very low earth orbit. With this satellite, the young company is researching fast Internet from space with very short signal propagation times and is doing pioneering work almost 300 kilometers above the earth,” emphasizes Dr. Walther Pelzer, board member and head of the German Space Agency at DLR, who commissioned the German government controls the German ESA budget, which is why it finances the tender for the VLEO project ( Very Low Earth Orbit) from the so-called ARTES program of ESA. If everything goes according to plan, the test satellite is scheduled to launch into space at the end of 2023.

Fast internet without long runtimes

In our modern world, good internet access should actually be a matter of course. There are also great demands on the high availability of mobile data supply. In Germany there are still numerous households that are not or only inadequately connected to the Internet. There are also major bottlenecks in the mobile connection away from the densely populated regions as well as in the aviation and shipping sectors. “In areas where terrestrial network expansion is not possible or economically viable, satellite networks that are already available today complement our communication infrastructure. There are more and more airlines that connect their aircraft to the Internet via satellite radio links.

The same applies to shipping. There are also already many initiatives that offer satellite-based Internet of Things (IoT) and the first satellite mega constellations for broadband services, ” emphasizes Dr. Pelzer. In addition to the growing need for more data transmission capacities, low latencies – i.e. short signal propagation times – are extremely important for some applications. Examples this includes virtual reality or augmented reality and certain applications in autonomous driving. However, many satellite connections reach their limits here: Due to the large distance between the satellites and the earth’s surface, the signals have a relatively long transit time, but this can be shortened by choosing lower orbits.

New orbit, new perspectives

Communication satellites, such as television satellites, are traditionally in geostationary orbit, about 36,000 kilometers above the earth’s surface. Constellations already exist in the middle earth orbit, about 8,000 kilometers above the earth’s surface. Others are under construction in low earth orbit at an altitude of around 500 to 1,200 kilometers. In the VLEO project, a satellite is now to be deployed on an even lower trajectory in what is known as the very low Earth orbit at an altitude of around 200 to 300 kilometers. In addition to the shorter signal propagation time, VLEO has some other properties – some of them positive, some negative.

Initially, launching the satellite will be easier. Due to the short distance to earth, less energy is required for communication, which makes communication technologies that are already used on earth, for example for 5G applications, more cost-effective. However, satellites in the VLEO fly over places on earth much faster than satellites in higher orbits. This leads to signal shifts that make communication more demanding. In addition, there is a relatively large amount of residual atmosphere in low orbits.

This is a curse and a blessing at the same time: On the one hand, atomic oxygen in these layers can attack the satellite’s devices. The remaining atmosphere also continuously brakes the satellite, which it has to compensate regularly with its engines in order to maintain its altitude. On the other hand, the strong braking force of the residual friction “disposed of” the satellite automatically when it has reached the end of its service life. The satellite, which is no longer in use, will burn up in the atmosphere within a few weeks. The very low earth orbit is thus self-cleaning – a very positive property that contributes to sustainable space travel.

Together towards the goal

The consortium around S4 GmbH now has the task of examining the influence of the VLEO on satellite communication. To this end, it will build a small satellite, launch it and operate it in the VLEO for several months to carry out various experiments. The start-up will lead the consortium, lay out the system, build it and procure the rocket launch. The global provider of communication payloads TESAT Spacecom from Backnang near Stuttgart will design and build the satellite’s innovative communication technology. The Center for Telematics from Würzburg – a sister company of S4 GmbH – is responsible for the necessary ground technologies and the operation of the satellite.