This content presents Differential SAR Interferometry or DInSAR analysis with GMTSAR (on Linux based OS, download DEM, prepare directories for processing). The case study is Nepal earthquake in 2015 using ALOS-2.

1. Kathm
andu
Pokh
ara
Center for Research and Application for Satellite Remote Sensing
Yamaguchi University
Differential SAR Interferometry Using
ALOS-2 Data for Nepal Earthquake

2. This content was created in January 2016
GMTSAR is old version but how to use software is similar.
Note

3. GMTSAR is open source (GNU General Public License) for InSAR processing.
The system has 3 main components
1. a preprocessor for each satellite data type to convert the native format and orbital information into a generic format
2. an InSAR processor to focus and align stacks of images, map topography into phase, and form the complex interferogram
3. a postprocessor, mostly based on GMT, to filter the interferogram and construct interferometric products of phase, coherence, phase
gradient, and line-of sight displacement in both radar and geographic coordinates
Advantages of this open source:
1. Some SAR images can be processed from raw image such as ALOS, ENVI, ERS, CSK.
2. InSAR relies on sub-meter orbital accuracy to greatly simplify processing algorithm
3. Process can be automatically processed with no human intervention
4. It provide user friendly interface so users who don’t know programming languages can access these applications easily.
5. It allows users to edit source code.
3
Source: http://topex.ucsd.edu/gmtsar/
Developers:
David Sandwell - Scripps Institution of Oceanography
Rob Mellors - San Diego State University
Xiaopeng Tong - Scripps Institution of Oceanography
Meng Wei - Scripps Institution of Oceanography
Paul Wessel - University of Hawaii
Software : GMTSAR

4. p2p_ALOS.csh
process an ALOS
interferogram
from end-to-end
Change
Parameter in
config file
Algorithm and codes for InSAR

5. DInSAR processing : Baja Earthquake
Sample data is provided in GMTSAR website http://topex.ucsd.edu/gmtsar/downloads/
Baja Earthquake, California, Mexico Magnitude, 7.2 (USGS, as of 2010-04-09)
Master image : 2009 (year) /351 (Day of year)
Slave image : 2010/124

6. Linux command
http://library.nd.edu/cds/textanalysis/images/Crclinuxpage.jpg

7. Linux command
http://library.nd.edu/cds/textanalysis/images/Crclinuxpage.jp
g

8. For window,
• Install “Oracle VM”
• http://www.oracle.com/technetwork/server-storage/virtualbox/downloads/index.html
• Download GMTSAR
• Install GMTSAR in Ubuntu virtual machine
• http://topex.ucsd.edu/gmtsar/downloads/
If you use Linux based systems (such as Ubuntu and MacOS),
It is better to install directly to your operation system
Install Program

9. Open “Oracle VM VirtualBox Manager” → click “New” to create virtual machine
Change name to “any name” and operating system to “Linux” type and “Ubuntu(32 bit)” version

10. Share your memory size for virtual machine → click “next”
Use an existing virtual hard disk file → select file GMTSAR_Ubutu.vmdk → click “create”

11. GMTSAR_Ubuntu32 is created in Oracle VM VirtualBox Manager → click “Start” icon

12. Open “GMTSAR_Ubuntu32”
This is GMTSAR version 4
Installed in Ubuntu 32 on window host

13. • DEM can be download from this website:
• http://topex.ucsd.edu/gmtsar/demgen/
Download DEM

14. Directory of GMTSAR

15. Install GMTSAR in command line
Open LXTerminal and type accordingly command line

16. Install GMTSAR in command line
GMTSAR is ready
to be used

17. Test program

18. Kathmandu
Pokhara
25 April 2015
7.8 Magnitude
Different SAR Interferometry
(DInSAR) Technique for Detecting
Nepal Earthquake Deformation
Nepal

19. Prepare folders for processing

20. Prepare config file and set parameters
We can change some parameters in this
file to be suitable for each images pairs

21. ALOS2 SLC DInSAR processing

22. Command to process DInSAR for Nepal earthquake
ALOS2 Images

23. Waiting for processing

24. Output file will be in “inf” folder

25. Result visualization in Google Earth