Receiving Images from SmallSat

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Is it possible to receive images from a SmallSat using the SatNOGS network? I plan on launching a SmallSat soon and would like to know if this is possible. Also, where can I locate the data received (on my Raspberry Pi) after an observation?

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In general yes SatNOGS is able to receive images. However you need to be more specific on the type of transmission, like what type of modulation are you going to use, in which frequency/band etc.

The data are saved temporarily in the memory, under the /tmp/.satnogs/data directory.

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Not sure what our modulation scheme is going to be just yet. I will find that out soon. On my raspberry pi, I can’t navigate to a .satnogs/data directory? This is what I haveCapture

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fredy,

I fixed my issue and was able to navigate to the data directory. User error lol.Capture

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You can’t see the ./.satnogs folder in /tmp with using ls - try ls -al instead :wink:

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The modulations that will be available to us are GFSK, 4GFSK, GMSK, and OOK. 433MHz

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This is sounding like one of the cheaper radio ICs… Which model in particular is it?
What license are you planning on transmitting under? The ISM bands (like the 433 MHz band you mentioned) cannot be used by satellites.

Also, are you fully aware of the amount of work ahead of you? There’s a heck of a lot of work required to bridge the gap between capturing an image, transmitting it reliably from a cube-sat, and then receiving it on the ground.

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Interorbital Systems is providing us with their TubeSat 2.0. The only specs they have provided are the non proprietary ones. Which are the specific modes I stated above and that the kit is tuned for 433MHz mostly for amateur radio license. The transmitter has a 1.5W amplifier as well. The reason for this thread is to investigate the feasibility of receiving images from a SmallSat in LEO on the SatNOGS network. If this is not feasible then we will look into sending different data this way. This is a learning experience for us as we are students participating in a university club. Thanks in advance for any feedback.

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The short answer is: yes, it’s possible, but it will take work.

  • You will need to apply to the IARU for frequency coordination to obtain a frequency in the amateur 70cm band.
  • You will need to design and document your telemetry format sufficiently well that packets can be decoded by other parties. Ideally you would provide a Katai struct which describes the telemetry.
  • As for imagery, you will need a way of piecing together images from multiple packets, quite possibly with many packets missing. Standard JPEG compression isn’t going to cut it here. SSDV would be an appropriate method of packetizing images in a suitable way, and has been used on a few satellites already: https://github.com/fsphil/ssdv
  • Also on the point of imagery - if you are operating from the US, then you will likely need to have your imaging device license through NOAA. See this post from the amsat-bb mailing list which explains what AMSAT had to do regarding the camera on FOX-1D: https://www.amsat.org/pipermail/amsat-bb/2020-February/076352.html
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