SAR technology is popular due to its relative cost-efficency as it enables users to monitor vast
areas. Free access to SAR data obtained by satellite Sentinel-1 of European Space Agency is a
remarkable opportunity. In this study, we are testing the differential interferometry technique
(DInSAR) in the area of Slovenia, known for its dense vegetation that results in low
coherence and influences results greatly. In the first part of the study, we analized
interferogram coherence values throughout the year for different land use. We concluded that
coherence reaches its highest values between November and March, when there is no snow,
on urban areas and on arable land. We used interferograms with best coherence in the second
part of the study, where we measured subsidence due to mining activity in the area of Velenje.
We compared subsidence results of DInSAR to those of GNSS measurements. To gain
acceptable results in the second part of our study, we had to reduce the test area down to a
small urban part of Šaleška valley. Some of the final DInSAR results were close to the GNSS
subsidence values. Low coherence and problematic phase unwrapping reduced the quality of
our results greatly, but we estimate that atmospheric influence on phase has also contributed
to the data quality degradation. Results of this study offer a good starting point for those who
wish to use Sentinel-1 data for radar interferomtery, especially in areas with dense vegetation.
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