Orekit has a neat feature - via SP3Ephemeris.getPropagator() - to interpolate P&V between the points in an SP3 data file.
Can anybody suggest how best to extend this over multiple (consecutive) SP3 files?
Obviously I could stitch a series of SP3 files together into a single file. This works, but it’s clunky and is susceptible to problems if the SP3 files differ in data period (for example 15-minute epochs versus 5-minute epochs).
I’ve also tried creating an Ephemeris object, using position data from the SP3 files. This works reasonably well, but gives different results to the “built-in” SP3 interpolator (typically to the order of 10-20cm, but occasionally as much as 2-3m).
Another approach would be to have a series of SP3Ephemeris objects, and select the appropriate one for a given timestamp. However, given the source SP3 data (from IGS), this would leave an inaccessible 15 minute period at the end of each day.
Any suggestions gratefully received!