Proposal: On-orbit verification for SatNOGS orbit determination


#1

Dear all,

I am cross-posting a post that I posted on the Orekit forum (https://forum.orekit.org/t/proposal-on-orbit-verification-for-satnogs-orbit-determination/526).

We at the Technical University Berlin are looking for experiments related to amateur radio for our next satellite TUBIN. This satellite will be launched in the second half of 2020.

We have seen the SOCIS 2019 project about SatNOGS orbit determination using Doppler measurements (@Noeljanes is working on it) and we thought it might be interesting that we at TU Berlin provide support for the operational verification. I read that you are already using reference data from the Max Valier satellite, but maybe you are interested in additional data for verification.

Here is what we could provide:

  • Reference PV data from our on-board GPS (10m, 0.1 m/s accuracy).
  • Reference PV data from laser ranging OD (even more accurate than GPS).
  • The means to the SatNOGS community to trigger our onboard UHF transceiver so that they can measure the Doppler shift when the satellite is passing over their ground station. We have had a Digipeater system on some of our previous satellites, it will not take us long to develop it for TUBIN. A Digipeater allows a ground station operator to trigger the onboard UHF transceiver to transmit either immediately (i.e. transponder) or with a delay (say, for a future ground station pass some minutes or hours later).
  • Flight dynamics support. We would be eager to contribute to the SatNOGS orbit determination and its verification.

We could maybe even start the SatNOGS verification with TechnoSat, which is in orbit since 2017, is referenced on SatNOGS (NORAD ID 42829) and is being tracked by laser ranging ground stations (example of orbit determination using the Orekit Python wrapper: https://nbviewer.jupyter.org/github/GorgiAstro/laser-orbit-determination/blob/master/02-orbit-determination-example.ipynb )

Such an experiment would help our application for a frequency allocation in the amateur band. This is why we would like to write a joint proposal Orekit - SatNOGS - TU Berlin.

Edit: Here are more technical details about our GPS system: we will fly a Phoenix receiver from GSOC. It provides both pseudorange and carrier phase in addition to the PV solutions. Our driver and telemetry allow downloading the pseudorange and carrier phase data.

Best regards
Clément Jonglez