Closed kautlenbachs closed 1 year ago
New implementation comparison with snap, full coherence chain with SFEP and full swath processing:
Same scene with current development branch:
Another dataset, new implementation per burst polynomial
Same scene as above with current development branch.
The improvements are due to improvements to subtract earth phase, other parts of the full coherence chain stay the same.
Coregistration and substract flat earth phase are quite sensitive to orbit interpolation accuracy.
These pictures show comparing snap results when changing the orbit interpolation degree parameter.
Subtract flath earth phase, orbit degree 3 vs 4:
Coregistraion, apply orbit degree 3 vs 4:
Snap uses jblas for polynomial interpolation of orbit state vectors in apply orbit file:
The mathematical solution isn't exact and different method have different accuracy - this explains a lot of the differences between ALUs and snap.
Purely changing the Ax=B solver method changes accuracy:
https://eigen.tuxfamily.org/dox/group__TutorialLinearAlgebra.html
FullPivHouseHolderQr:
JacobiSVD: