TopSAR Processing


#1

Hi everyone,

i am trying to detect deformation on faults by using sentinel SLC IW data but i am a little confused about the steps that i should apply;

  1. My first step of every image is ; Splitting, Debursting and Merging the data and after i create a Subset with only VV or HH band (because i am only interested with these bands)

  2. After doing upper steps for all my images ,do i need to follow ;

  • Radiometric—Calibrate
  • Multilooking the image ( I dont know what i am going to choose for “Number of Range and Azimuth looks”)
  • Speckle filtering–Single Product (After i apply this to the image, when i am making coregistarion snap is saying “this product is no longer SLC data”)
    -Terrain correction (Range-Doppler TC)

Plz Help


#2

In your first step make sure to apply the corrected orbits.
For insar processing you don’t need calibration or speckle filter.
Have a look at the insar tutorials at http://step.esa.int/main/doc/tutorials/
and especially at http://www.esa.int/About_Us/ESA_Publications/InSAR_Principles_Guidelines_for_SAR_Interferometry_Processing_and_Interpretation_br_ESA_TM-19


#3

Thanks for reply @lveci

i have all these tutorials and i also studied them and studding as well
but I confused in my this study
what i Do…??


#4

for deformation:

  1. S1 TOPS coregistration with ESD
  2. Deburst and Subset
  3. Interferogram Formation
  4. Topographic Phase Removal
  5. Goldstein Phase Filtering
  6. Snaphu Exprort
  7. Unwrap via Snaphu
  8. Snaphu import
  9. Phase to Displacement
  10. Range - Doppler Terrain Correction
  11. Choose a reference point
  12. Final map
    This is a basic processing

#5

Needlessness of calibration in InSAR processing made me wonder…
I understand that calibration is needed for backscatter, especially for comparing data from different dates and view angles.
If I calibrate SAR data and keep them in complex format, it doesn’t harm coherence estimation, am I right?
(my processing chain begins with split - apply orbits - calibrate, to prepare both coherence and backscatter statistics from these two calibrated images)


#6

yes, complex calibration preserves the complexity of the signal which is needed for interferometry.


#7

Thanks @vasilisgeo88 and @Zane
But when is applied S1 TOPS coregistration with ESD
This Error is occur :frowning:


#8

the orbit file for 04-feb-2017 SLC is missing. Try to download it from https://qc.sentinel1.eo.esa.int/ and place the downloaded file into the auxdata folder or choose an other SLC product.


#9

@vasilisgeo88
There is No Orbit File Available At https://qc.sentinel1.eo.esa.int/ of 04-feb-2017 SLC
What I Do now.??


#10

according to your screenshot your image is from 04.02.2017 at 13:51

Find the correct time here and dowload the orbit file:
https://qc.sentinel1.eo.esa.int/aux_resorb/?validity_start_time=2017&validity_start_time=2017-02&validity_start_time=2017-02-01..2017-02-04&validity_start_time=2017-02-04


#11

Thanks @ABraun for Reply
But My Image Time is not available :confused:


#12

@vasilisgeo88 @ABraun @lveci
When I Applied Orbit File
This Errors Is Appear :confused:


What Can I Do…??


#13

isn’t this the right one?

S1A_OPER_AUX_RESORB_OPOD_20170204T 130942 _V20170204T084844_20170204T120614.EOF
https://qc.sentinel1.eo.esa.int/aux_resorb/S1A_OPER_AUX_RESORB_OPOD_20170204T130942_V20170204T084844_20170204T120614.EOF

You can also search here:
https://s1qc.asf.alaska.edu/


#14

@ABraun
My Image Time Is 13:50:39


#15

so it’s between 13:03 (mentioned orbit) and 14:33 (next orbit). These files are valid from the given time until the time of the next.

There is no separate orbit file for each SAR image, they just determine the position of the satellite every ten seconds.


#16

@ABraun
I Followed Your All Instructions But Same Error :’(


#17

ABraun’s instructions are totally right but if you can’t solve the problem just download an other SLC product and check coherence and baseline so the pair will be valid for defo application.


#18

“Java heap space” indicates memory issues. How much RAM is available?


#19

@ABraun
This Is my System Specification


#20

@Zane @ABraun @lveci
Sorry for Disturbing
While I Applying Coregistration
This Error Comes Out


Why…??
Any Solution.??
Please Help