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Space Satellites Power Enhanced Connectivity on Earth

Image courtesy NASA

My house has a 30 Mb/s internet connection that I use to stream entire movies. I talk to people on the other side of the world and participate in virtual meetings on my mobile phone, which fits in my pocket and works everywhere. I also use my mobile to drive through cities I’ve never seen before, following the best route as determined from satellites in space that track the location of my phone using GPS coordinates. You are probably thinking “so what?” because you, like billions of other people, have the same kind of connectivity. This is what should impress you most: We are so used to this easy connectivity that we have forgotten how incredible this technology is compared to what we had 20 years ago. Engineering simulation played a big role in getting us to this point, and it will play and even bigger role in the future.

Growing complexity

We are just at the beginning of a communications revolution that has accelerated in the last few years, pushed by global trends and initiatives like Industry 4.0, IoT and autonomous systems. All of these technologies are based on data connectivity. Forecasts are telling us that connected devices will grow from 15 to 75 billion in 10 years. Unmanned drones are getting ready to move goods and people around our cities. Digital twins will soon be able to a give us insight and early warnings of a pending system failure in an airplane flying over the ocean, so measures can be taken to avert a tragedy.

Many of these applications are safety-critical, and can only work with very robust and reliable connectivity. The average speed and bandwidth must be large enough to ensure an uninterrupted 24/7 connection capable of moving the terabytes of data each system will generate in a single day. And the network must cover the entire globe, so moving vehicles like airplanes are always connected.

The role of space

We have been relying on satellites for global communications for more than 50 years now. Fifty percent of new satellites are dedicated to connectivity, with other key applications being GPS and earth observation activities.

Reliability and endurance are key engineering challenges for satellites, because they must work in the harsh environment of space for an average of 15–20 years before they have a critical failure or run out of fuel. Technology advancements are also needed for the higher speed 5G connections and KA-band high-throughput satellites of the future. For a wide network of global services powered by satellites, we need to increase their performance while reducing their cost across the entire satellite lifecycle, including not only their design and assembly but also their launch into orbit and mission management.

Emerging trends in satellite design

In 2017, 75 percent of the satellites we sent into orbit were smallsats (small satellites), with a mass below 500 kg, and many below 100 kg. Taken together, these smallsats account for just 1 percent of the mass we launched.

This trend is here to stay, with experts saying that smallsat demand will rise by a factor of 7 in the next 10 years. They predict that making smallsats will be so cheap that university student teams will build their own.

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A different approach is represented by high altitude pseudo-sats (HAPS), which are unmanned aircraft that operate at the edge of the atmosphere and can stay aloft weeks or months. They have a lower cost compared to satellites, can be deployed in a short time and don’t need a launcher. HAPS projects include Facebook’s Aquila solar powered drone and Google’s Loon balloon-powered internet. They are also used for disaster surveillance, maintaining and growing communications and connectivity, earth science research and weather forecasting. They are generally intended for temporary, even if prolonged, deployment.

Image courtesy NASA

What will be the winning model? Probably a hybrid involving traditional satellites coexisting with swarms of microsatellites and HAPS to create a robust, reliable network.

Different solutions but similar engineering challenges

Despite their differences, both microsatellites and HAPS share some engineering challenges:

  • They need to be as light and compact as possible to minimize costs. Topology optimization and additive manufacturing are already being used for this purpose.
  • Most systems are powered by electricity that must be generated, stored, distributed and used by reliable, low-consumption systems. Optimization requires advanced design exploration techniques and a system analysis to ensure maximum performance during the entire lifecycle. Electrical consumption has a significant impact on endurance as well, and is among the top concerns of designers.
  • To fulfill their missions, some systems are critical: antennas, sensors, cameras and high-performance electronics. Simulation can help with EMI analysis, signal integrity, thermal management and the high stresses during launch that must be taken into consideration.

A lift to space

While HAPS don’t need a launcher, all the other satellites need one. This can be a huge problem not only because of the cost (which depends on weight), but also because launches are infrequent. A satellite can wait for months or years before getting a lift, and the wait will only get worse. While traditional launchers are thinking about how to use their spare capacity to host smallsats, a number of new players like SpaceX and Vector in the U.S. and PLD in Europe are entering the market with low-cost rockets that can be launched frequently because they can be built faster and reused.

These companies are also facing other challenges, like designing new propulsion systems and new fuels; innovating avionics and flight controls to perform critical maneuvers and ensure reusability; and learning how to manufacture launchers less expensively, so they can perform dozens of launches per month.

Speed up innovation through simulation

I spent weeks last summer visiting new companies that are taking advantage of our Startup Program to use ANSYS simulation to explore new propulsion systems, launcher designs and high speed communications satellites. These companies are bringing fresh ideas to challenges we could not envision a couple of years ago, including additive manufacturing, complex systems optimization, electrification, sophisticated power electronics and antennas, and complex embedded software.

I’ve already written a blog on why these newcomers are thriving and revolutionizing an entire industry: They know the real power of a simulation platform to explore a very complex and revolutionary system. We can learn how to accelerate innovation through simulation from them. Do you want to know more? Watch this video to see what Vector did, and keep an eye on our next issue of Dimensions magazine.