Collaboration with the Duchifat-3 satellite

Hello, my name is Ido, I am a student in the Duchifat/Hoopoe satellite project in the communications team. I am working on a communications solution for our next satellite (Duchifat-3) based on Gnu Radio and a LimeSDR board (TX and RX). The project is at: if anybody wants to take a look. I have been in contact with Daniel the creator of gr-satellites and Manolis Surligas who is the maintainer of gr-satnogs, and I am working on a receiver based their design (BPSK@9k6 AX.25). We are also using Gnu Radio with LimeSDR for TX (AFSK@1k2 AX.25). The goal of this project is for a self-contained and automatic communication solution for our satellite, for this, I have also created a Doppler correction script based on SkyField library (since pyEphem is deprecated), and a rotator controller based on rotctl using pipes (instead of sockets in satnogs-client, seems more robust). I am still working on an automation script at the moment. Just for context, our programming team created a ground station manager software that generates the packets for us and receives the data for farther processing.
After taking a look at the amazing Ground Station network and the Satnogs project you have created, I have some ideas for shared projects:

Our next satellite (Duchifat-3) has a camera as a payload and is set to launch in June-July of this year. The full resolution image files are rather large for a 9k6 BPSK Downlink (about 2 Mb), and so, even in a perfect pass, we can only download about half of the image file. This is a big problem for us, and so I thought that perhaps we could join forces, and use the Satnogs ground station network to schedule a dump of image data when there is a pass over a ground station in the Satnogs network. This would mean we would be able to download many more images that we would normally be able to with our one ground station.

I would imagine that for a project like this to work, we would need the ability to get satellite passes over ground stations in the satnogs network, does that kind of API already exist?

I would also love to work on a dashboard for our satellite in Satnogs Dashboard, we could also share the downloaded images there!

Let me know what you think of the idea, and if you have any other ideas for shared projects, harnessing the power of a ground station network in a satellite mission would be awesome.


Hi Ido,

It’s great to see people from satellite teams to come here to discuss their satellite missions with the community, especially when that happens in the early stages of the project. :slight_smile:

There are API endpoints on both Network and DB for getting results of decoded data from observations. The one on the network contains the observations from the network, while the one in DB has data from both Network and external stations.

In the past, data from DB have been used to decode images from satellite so it should work fine in your case too.

That would be great! I’ll leave the details on the kaitai stuct and how this can lead to a dashboard to @DL4PD, as he is our expert on this part of the SatNOGS project.


Hi fredy, sorry for the delayed response, thanks for the help!

Our satellite will only send image data if a command is first sent to it, we have the ability to send a delayed command that will execute in a later time, so what we need is an api to get future observations of ground stations in the Satnogs network for our satellite, so that we could plan our commands.

Great! We will be looking forward to working on the dashboard.

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That’s already possible via Jobs API in network, which shows all the future observations. You can filter the results with satellite norad id and also there are a couple more filters that you can use, like start/end time, station id and others.



may I ask where the definition of the data structure is documented?

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Any news on the data format description?


Check the Herzliya Space Lab GitHub page.

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An example of a decoded packet:


What is the structure of the data? Which value is located where in the bytestream?

The Duchifat-3 team has released the precise structure of the data.



Hello, I’m Nikita from the GS software team of Duchifat-3.
First of all, I’m sorry for the long delay of our response. From now on, I will manage everything related to the dashboard for our satellite, and will make sure you have all the necessary information.

@DL4PD What formats are you looking for?


Hi Nikita!

I am very sorry but I must have missed the latest response of @teslak20!
It’s a pretty busy time currently, but I can have a look at your data in the next days!

Let me check what is missing…


Are there any news?
We would really like to work with the SatNOGS dashboards. How can we create a dashboard and what additional format information do we have to provide?

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I am going to list everything neccessary this UTC evening!

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Ok, here we go:

This looks pretty correct from the first glimpses!
I need to add some specials to integrate it into satnogs-decoders (which will take just a few minutes now!) and after merge and deploy into satnogs-db we can start decoding those frames. Once this has started, we could start working on a dashboard at If you like to join that dashboard work: please contact me through direct message and login into the auth0 system while visiting the dashboards main site!

Awaiting your response :smiley:

I can see some frames of different type, that are not yet documented in the posts above, they start with a different type identifier 0D instead of 03 - is there a documentation for them available, too?

8E A6 40 40 40 40 E2 68 B0 68 90 A6 98 63 03 F0 0D 5A 00 06 5E 31 3F 0D 00 00 03 EF 00 00 

See observation