Difference S1 IW SLC /GRD products

Microwave Toolbox
#1

Hi all, today my question is about S1 IW SLC /GRD products. I find a lot of information about differences between the two products but at the end I have not understood which product is more useful for example for soil/water detection. someone can help me?
Thanks in advance.

William

#2

GRD products are produced from SLC products. For soil/water applications it may be easier for you to use the GRD products unless you need complex data.

#3

Hi, I tried to do a soil/water detection too.
I’m using GRD products and I did the following processes:

  • Terrain correction;
  • Extrapolation of Sigma0 (converted in db);
  • Histogram to Sigma0_db intensity and I found the two peaks;
  • Band Math to select pixels with low intensity value.
    The result is not really nice: I can locate mayor rivers and lakes but also many other pixels that don’t represent water are selected.
    What process could I use to improve my workflow?
    Thanks in advance,
    Elisa
#4

Try speckle filtering first and pay attention to the slope using the dem.

#5

SLC is only needed for inteferometric applications.

A standard method for detecting water-bodies is to exploit the large backscatter-difference between calm and windy conditions.

#6

I want to research urban vegation,I should use GRD or SLC ?

#7

I’d say stacks of SLCs, there might be something interesting in the InSAR coherence.

#8

OK,Thank you for your suggestion,I will try to do it

#9

Also, look into volume scattering with the H-Alpha decomposition and Wishart classifier. Calibrate the SLCs first with complex output.

#10

Thanks for your attention

#11

I’ve seen in other comments that SLC is needed for Polarimetry as well, is this incorrect? I am trying to figure out whether I can use GRD products or need to use SLC products when looking at biomass for forests and crops, with the intention of performing polarimetric decompositions.

And as a follow up question, is the applicability of GRD vs SLC products fairly consistent across sensors/software? I am coming from limited experience using the PolSARpro software to perform polarimetric decompositions on GRD formatted data (UAVSAR), and now am wondering if I was performing incorrect processing or if it is just a difference in software/sensors. Thank you!