Evaluation of Atmospheric Effects on Interferograms Using DEM Errors of Fixed Ground Points

Area of Science:

• Geosciences
• Remote Sensing
• Geodesy

Background:

• High-resolution synthetic aperture radar (SAR) data are crucial for disaster monitoring.
• Accurate interpretation of SAR interferograms requires understanding sensor specifications, acquisition conditions, and land cover.
• Previous research established methods for estimating interferogram phase noise using TerraSAR-X and TanDEM-X datasets.

Purpose of the Study:

• To estimate atmospheric effects on SAR interferograms.
• To differentiate atmospheric disturbances from other sources of digital elevation model (DEM) errors.
• To quantify the contribution of atmospheric effects to phase noise in interferometric SAR (InSAR).

Main Methods:

• Comparing digital elevation model (DEM) errors between repeat-pass and single-pass interferometry.
• Utilizing TerraSAR-X and TanDEM-X datasets for analysis.
• Conducting quantitative analysis of DEM errors at fixed ground objects in Tsukuba city.

Main Results:

• Single-pass interferometry exhibits reduced DEM errors due to minimal temporal decorrelation and atmospheric disturbances.
• Atmospheric effects were estimated to account for 75% to 80% of the total phase noise in interferograms.
• The study successfully isolated and quantified atmospheric contributions to phase noise.

Conclusions:

• Atmospheric disturbances are a major source of phase noise in SAR interferograms.
• Understanding and quantifying atmospheric effects is essential for improving the accuracy of disaster monitoring using InSAR.
• The proposed method provides a valuable approach for assessing atmospheric impacts in InSAR applications.