Satellites telemetry in JSON format

Hi everyone,

I would like to talk about satellite telemetry. Right now, SidS protocol can accept telemetry data, but only in binary format. That means everyone can send anything in these bytes. Even if r2cloud integrated with Satnogs and sends the data via Sids, this data do not interpreted in any way.

So I decided to expose this data in JSON format via API:

https://r2server.ru/api/v1/telemetry/42017

Since every satellite has its own telemetry format, I’m using JSON with free-form fields.

I hope one day, this data will be used in Satnogs dashboards :slight_smile:

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Hey @dernasherbrezon,

Thanks for sharing your API. I can see in there that the data you share are in decoded format.
You might have a slight misunderstanding about SIDS, since SIDS transfers demodulated but not decoded data

please see the following image for clarification on current data flow:

ps. please can you point to your license and live server too?

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This is completely decoded telemetry. What is very unfortunate: you won’t be able to make corrections without having access to the raw frames. That’s why we are exposing the raw frames in satnogs-db. We’ve seen plenty of faulty telemetry descriptions until now.

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Yes, that what I was trying to solve. If you want to analyze telemetry, then you have to write decoder first. Which is hard using SiDS data. SiDS data can contain sync bytes or may not. Or it can contain all packets headers or maybe not.

https://r2server.ru/api

License: Apache 2.0

Yes, I have raw data frames. They are available under “/observation” endpoint. If any issue found with the decoder, then I can re-generate JSON-based.

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Hey @dernasherbrezon,

Great! Then you can continue to submit those raw frames using SiDS to satnogs-db. Upon upload they will be decoded by the satnogs-decoders and then forwarded to the database behind SatNOGS Dashboard (technically the decoding & upload is handled by a periodic task which is run every 15 minutes).

So, to get the decoded data for a satellite into the database for the dashboards there must be a decoder available in satnogs-decoders for this specific satellite.

You showed decoded telemetry for 42017 - NAYIF-1 in your first post. Currently there is no decoder available for Nayif-1. If you are interested in adding such a decoder, please follow this guide. If you have any questions, feel free to ask them here.

Best wishes,
kerel

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I just had a deeper look on the source code for r2cloud at github and realized that the decoding of telemetry in r2cloud is performed using the decoders in your jradio project.

There are multiple satellites which are supported both by jradio and satnogs-decoders, so they are good examples on how to add a decoder to SatNOGS based on jradio, see the following table:

Some satellites are supported by only one of the two tools. satnogs-decoders is describing the protocols using Kaitai Struct. Kaitai has Java support, so in principle it is possible to add parsers for satellites currently only supported by satnogs-decoders to jradio.

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Yes, I can convert supported satellites to kaitai structures.

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