(Photo: Sujay Narayana) Humans of TU Delft
“I was supposed to be finishing my PhD around November, but it’s taking some extra time because of the lockdown.” (Photo: Sujay Narayana)

In order to miniaturise satellites, PhD candidate Sujay Narayana says you have to overcome energy challenges. His PhD is taking some extra time because of the lockdown.

“My research is mainly focused on miniaturising satellites. They are getting smaller, in part, because of huge costs related to launching. For example, it might cost more than USD 20,000 just to launch a 1 kg satellite, not even including costs for the development. Now assume that you have smaller satellites that are capable of doing the same job. Things get smaller and you can launch multiple satellites for the same cost. Let’s say one satellite is lost, but you still have the rest working so it’s not like a complete mission failure. A part is gone but the majority is still there. And multiple satellites can do more jobs than one satellite can do.

I’m working towards miniaturisation, making them smaller, but the issue is that when you make them smaller you have energy problems. That’s because all of the solar panels and energy harvesting systems also get smaller. But that doesn’t mean that energy consumption will be less. Incoming energy will be less, but the consumption may be the same as before, or only a little bit less. I’m solving these energy issues by working on the embedded systems, mainly in the context of Space Internet of Things.

We have developed a tiny GPS receiver for space applications and it concentrates on saving the energy consumption. Let’s say you have a mobile phone that is switched off for a long duration. You turn it on and you have to wait for some minutes to get the GPS location fixed. If there’s internet, it’s faster but that’s not available in space. So how do you reduce the time it takes to get the location fixed? That’s what we’re doing with respect to satellites.

‘The faster the fix, the less time the GPS has to be on’

When these satellites tumble (rotate), they have a GPS antenna pointing in a certain direction. When a satellite rotates and the antenna moves, it misses the signal from the GPS and you can’t compute the position. So, we are working on trying to design a low-cost, low-power GPS receiver that gets the location faster by improving the Time To First Fix (TTFF). The faster the fix, the less time the GPS has to be on. There are many challenges, but my work is focused on getting a faster time and solving the energy challenges.

I’ve been here in India since March and I’m actually waiting now for flights to Europe to start again. I hope to be back in the Netherlands in 15 days. I was supposed to be finishing my PhD around November, but it’s taking some extra time. I haven’t been able to do much since the original lockdown because my research requires access to equipment, especially from space research organisations, and they are not available now. I can’t work because my entire lab is there in the Netherlands.”

Who are the people who work and study on campus? We meet them in Humans of TU Delft. Want to be featured in this series? Or do you know someone with a good story to tell? Send us an e-mail at humansoftudelft@gmail.com