1. InSAR Processing and Applications1

2. Introduction
William Blake – Aviation Software and Systems Engineer for the Weather Radar Group
With Garmin since 2010
B.S. Co.E. in 2005 from University of Kansas
Ph.D. E.E. in 2010 from University of Kansas
What do I do?
Make pretty pictures
Where do I work?
Depends on the day

3. InSAR Applications Many applications for InSAR Processing
Fine resolution 3D imaging
Monitoring of changes over time 3

4. InSAR Applications 1st InSAR missions SeaSat 1980
Since then ERS-1, JERS, RadarSat-1, ERS-2 …
SRTM (Shuttle Radar Topography Mission) 4

5. InSAR Applications Airborne surveillance
Deformation after natural disaster
Changes in road conditions
Planetary surface mapping 5

6. InSAR Applications
Changes between two scenes (Coherent change detection) 6

7. InSAR Processing 3 Main processing steps (Satellite based processing)
Data Search
Data Processing
Product Validations
Subtle challenges based on platform and geometry 7

8. InSAR Processing – Data Search
Need two complex SAR images
Not too far apart in space ~80 m (spatial decorrelation)
Not too far apart in time (temporal decorrelation)
Frequency band
Spatial resolution 8

9. InSAR Processing – Data Processing9

10. InSAR Processing – Data Preprocessing
Need two SLC SAR images
Accurate position, collection geometry
Data collection parameters (headers, etc.) 10

11. InSAR Processing – Coregistration
Start with multiple SLC SAR images with separate baselines
Co-register images
Coarse registration (Full pixel grid registration)
Fine registration (Sub pixel grid registration)
Resample one image to the other
Calculate baselines 11

12. InSAR Processing – Interferometric Products
Calculation of Interferogram
Some parts of image may have “noise” segments 12

13. InSAR Processing – Phase Unwrapping
Unwrapping may required advanced algorithms to ignore or work around issues 13

14. InSAR Processing – Phase Unwrapping
Unwrapping may required advanced algorithms to ignore or work around issues 14

15. InSAR Processing – Geocoding
Take DEM and put latitude/longitude/elevation 15

16. InSAR Processing – Challenges
Many challenges at various steps
Focus on two
Speckle
Layover/Shadowing 16

17. InSAR Processing – Challenges
Speckle due to homogenous terrain scattering 17

18. InSAR Processing – Range Cell Resolution
Slant range resolution cells independent of terrain 18

19. InSAR Processing
Layover/Shadowing happen when terrain variation masks features 19

20. InSAR Processing – Other Platforms
Experimental data has it’s own challenges 20

21. InSAR Processing – Other Platforms
May have multiple returns
Must choose the return that needs to be imaged 21

22. InSAR Processing – Other Platforms
Actual created SLC images 22

23. InSAR Processing – Other Platforms
Coherence Values 23

24. InSAR Processing – Other Platforms
Interferometric Phase Products 24

25. InSAR Processing – Other Platforms
DEM, Geocoded 25

26. InSAR Processing – Other Platforms
Comparison between basic interpolation and InSAR terrain estimation 26