Combine SP3 and Rinex for IOD

Hi. I apologize if this question has been asked before, but is there a standard function that will allow the user to essentially input GPS orbit sp3 files and satellite Rinex files with range measurements for the various GPS satellites, and then use those inputs to automatically do TOA geolocation with compensation for GPS clock drift and get out estimates of the satellite position values over time that you can then plug into an IOD algorithm like Gibbs or Gooding? I’ve been over the tutorials and the IOD functions in orekit.estimation.measurements, but Java is not my primary programming language and I could easily have missed something.

There is no simple function to do that. You would have to set up the measurements by yourself and their API was really designed to be called from an orbit determination process, which means it needs quite a heavy preparation.

You would anyway have to solve a preliminary tough problem: getting the clock offset of your own spacecraft, the one for which you don’t have an SP3 file. As GNSS pseudo-ranges are one-way measurements, they need accurate and stable clocks. This does not seem to be consistent with an IOD process.

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OK, thank you for the help. I’m glad I didn’t overlook anything.