DEM

Corrected DEM

MintPy estimates DEM residual in time-series domain using Fattahi and Amelung's method (2013, IEEE-TGRS), and output an estimated DEM residual value for each pixel into file demErr.h5. It can be used to generate a new, corrected DEM after masking and proper deramping, using the command below.

mask.py demRadar_error.h5 -m maskTempCoh.h5
add.py demRadar_error_masked.h5 demRadar.h5 demRadar_cor.h5

To better under this correction approach, please keep in mind:

1. InSAR measures relative range change, so does this step. Thus, this estimated DEM residual is with respect to the reference pixel, which has zero DEM residual.
2. Fattahi and Amelung (2013, TGRS) method estimate phase components correlated with perpendicular baseline history, which should mainly be DEM residual; it also contains the correlated part from temporal deformation or orbit error, if they are correlated, or partially correlated with perpendicular baseline history.

Reference

Fattahi, H., and F. Amelung (2013), DEM Error Correction in InSAR Time Series, Geoscience and Remote Sensing, IEEE Transactions on, 51(7), 4249-4259, doi:10.1109/TGRS.2012.2227761.