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Er worden posts getoond met het label FFT

Work of a student: starting his own blog!

Afbeelding
The DopTrack satellite tracking station is in full operation these last weeks. In the Space Minor at the university during my module "Satellite Operations", students are visiting the station and record satellite signals, especially Delfi-C3 and the ISS are very popular. The students then need to determine the Time of Closest Approach (TCA) and the corresponding frequency (FCA). This requires some FFT, but I am confident that they will manage. Furthermore, our intern student has done work on the ground station. His job is to estimate the precision of the Doppler measurements of DopTrack. The last few weeks he has been working at the theory behind the Doppler measurement and some of its characteristics. So with the motto "More scientists and engineers should blog", I asked him to write a blog post about his finding. His results give a clear description about the Doppler measurement. Please follow the next link for his work: http://msondergaard.blogspot.nl/201...

How to make a spectrogram or waterfall plot

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In a few blogpost ago, I showed you several figures of a satellites transmission. You know, those beautiful S-curve plots with all the colours.  Those are called spectrograms or we like to call them waterfall plots, because the radio transmissions streams up in time like a reversed waterfall. To see such a waterfall plot live in action, the University of Twente opened their antennas for you to listen and see (see link ). Yet, how to make such a figure? To start with you need a recorded radio transmission. When the website of the TUDelft tracking station is up and running you can download some data there. However, (Start NerdAlert!) you can also buy your own little USB stick that acts like a software defined radio (SDR) receiver like the Logilink DVB-T . For only 20 euros you have your own satellite tracking station. NOTE: Beware! You need the RTL2832U chip version, because a lot of open software is written for that device. It is almost plug and play, you need some software, b...