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Normally I wouldn’t write here about what I do at university, but this is so exciting that I have to share it — videos below. Since September me and my group at Aalborg University (AAU) have been working on a project called GENSO (Global Educational Network for Satellite Operations). It’s an international project supported by ESA, NASA, JAXA, and other space agencies, and lots of people participate. For our project this semester at AAU we’ve been developing a ground station server for GENSO.

Maybe a short introduction to what GENSO is about would help. A basic problem when communicating with satellites is that you’re only able to talk/listen to a satellite while it’s over the horizon. GENSO aims to solve that problem by establishing a network of ground stations all over the world which are connected via the Internet. Using the network you will be able to communicate with your satellite whenever it’s above any GENSO ground station, and not only your own. Better yet, the GENSO network will collect data from your satellite autonomously whenever it passes over a ground station, and send a pass report to you with the data received.

GENSO is in its alpha test phase, and only downlink is implemented, i.e. you can’t transmit. But still tracking satellites requires lots of stuff going on at the ground station, like predicting when satellites are passing, controlling antenna rotators and modems, and setting Doppler corrected frequencies on radios during a pass etc. This and more is what the ground station server is taking care of.

The cool thing about it is that now the project has reached a state where you can actually just start the ground station server, leave the server and the hardware alone, go somewhere else and wait for data rolling in once a satellite is over the ground station. We even implemented a live audio stream that you can connect to during the pass to hear what is received by the radio.

We already made a number of successful proof of concept passes at workshop V here in Aalborg back in early November. (Actually the picture to the right shows the participants at the workshop enjoying a celebratory roof-beer while the ground station is controlling the antenna behind us during a pass.) But not until now the system has been running completely autonomously exclusively on the hardware available at the AAU ground station.

What I’d like to show you is a couple of videos showing part of a CO-57 pass over the AAU ground station. I followed the pass from my computer at home, and no human interaction with the ground station was taking place.

Videos:
Video 1 (5.36MB) | Video 2 (33.2MB)

Pictures:

What you see on the screen in the videos and on the pictures above is: Upper left: Web-cam in the radio room at AAU. Lower left: GPredict running locally (just to see which satellites are available). Upper right: Debug output from the ground station server (setting azimuth, elevation, and radio frequency). Lower right: The GUI of the ground station server showing the passes that are scheduled within the next hour at the bottom. (The red bar to the left indicates the current pass.)