BatchLSEstimator with geo orbit data

Hi All,

Is it possible to use BatchLSEstimator with geo satellites ?
The .estimate() line does not seems to terminate when I feed geo range rate data, captured for 10 minute time interval .When the capture window is small I get the error is “singular problem”.
Does the BatachLSEstimator parameters (propagator/optimizer)or leo and geo orbit has to be different ? if so how ?

Thank you.

Hi @niluj,

Yes ! BatchLSEstimator is independent of the type/altitude of the orbit.
It relies on one (or several for multi-sat OD) propagator where the dynamics is modeled.
Be careful to adapt the force models (use geopotential 8x8, Sun/Moon third bodies and SRP) to GEO orbits.

What maximum iterations/evaluations of the estimator did you set ?
You could benefit from setting a BatchLSObserver to see how your estimated orbit evolves after each iteration of the batch LS (example here).

This often means that the Jacobian matrix of the problem cannot be inverted.
It can be a configuration problem in the measurements. Check the units to start with, everything should be in SI when given to Orekit (station coordinates in radians/meters, range in meters etc.)

Orbit estimation with geo works well.
Beware however that due to the specificities of geostationary orbits, observability may be poor in some cases, like using only one ground station, or use of range-rate, or simulated measurements on a theoretical perfect geo orbit.

Thank you. This is helpful.