Dear all,

I am currently try to simulate the performances of a spacecraft with a payload characterized by a range of incidence angles on ground. The method I have used in the past consisted on fixing a roll angle for the whole simulation, and around one body axis I centered a DoubleDihedralFieldOfView in which one angular aperture is very close to 0, and the other is representative of the aperture of the antenna. In this way, I obtain with the method getFootprint the range (on a line) of points seen on the ground characterized by that FoV.

If tuned correctly adopting spherical Earth geometry, it is possible to estimate roll and FoV angle based on the incidence angles, used as constants throughout the orbit. I wanted to know whether it is possible to use only the incidence angles on ground as inputs instead, and modify during the propagation the roll angle of the spacecraft to guarantee this incidence angle range on ground, since there are variation caused by the oblateness of the Earth.

To speed up the procedure one could also just maintain an attitude fixed with LVLH (without roll rotation) and create one or more FoVs around some body axes vectors, but the vector around which the FoV is centered shall change during the propagation, to be representative of the roll rotation.

Furthermore, would adopting the mean elements for the propagation still be good for the coverage analysis? In the past I have adopted a numerical propagator, with the aid of @luc , in which a correction of the orbital semi-major axis estimated the correct osculating semi-major axis to be used as input for the repeating ground track orbit.

Using a propagation with mean elements is faster and also skips this step, since I could directly use the average semi-major axis obtained from theory for a RGT orbit. I was wondering whether this solution would provide realistic values for the coverage, or not.

Thanks,

Antonio