Elaborate S1-GDR images to obtain FSMH (forest stand mean height)

FORESTS GDR S1.docx (3.0 MB)

image

Hello everyone,

I need help to understand what kind of elaborations i do to obtain SAR Back scatters VV and VH images that is used in this paper to obtain FSMH model. someone can help me?

If you apply Calibration to Sentinel-1 images you get the backscatter coefficient Sigma0.
Please also have a look here: What is sigma0

Maybe this also helps you: Radiometric & Geometric Correction Workflow

Thank you for reply ABraun,

now I’ve another question for you. If I have two or more GDRH images in different times, but with small difference time between them, to link them to obtain a single product that is more accurate: what kind of elaborations I do? I have to elaborate single images, like in the workflow you suggest me, and than apply an interferometry or I have to link them before elaborations and than apply the workflow you suggest me?

Thank you for all

I’m not sure if I undestand what you mean with this.

Sorry, I try to explain,

I understand that when I elaborate a single image, that image can be have some errors that is respresents by shadow zones or other kind of distorsion of the image. Instead, when I use a serie of images, and link them to correct errors, a single pixel of the final image have a medium value among all pixes of all images that I use for that multitemporal correction (for example when I apply a multi-temporal speckle filter). Isn’t it a way to get a more accurate image? Sorry, I’m a student,and it’s my first time with the Sentinels-1 images and SNAP program.

if you create a stack of your images (after pre-processing) and then use
Radar > Coregistration > Stack Tools > Stack Averaging

you can create a mean image of all the inputs. Would this help you?

Yes ABraun, thank you,

now I’ve 4 S1B_IW_GDRH_1SDV images, I want obtain a SAR backscatters, VV and VH, like in the paper I posted. I’ve set this workflow, please tell me if is correct for you

For all images I apply:

  • Thermal noise removal
  • Apply orbit file
  • Calibration (in Sigma0 and in Beta0)
  • Radiometric Terrain Flattening (with default values)

now I want to proceed with speckle filtering, I have to use multi-temporal speckle filtering and than, after apply doppler terrain correction, use coregistration or I have to use single product speckle filtering and Doppler terrein correction for all images and finally use coregistration?

if you want to perform multi-temporal speckle filtering, you have to create the stack first (by coregistration).
You can then terrain correct the entire stack as a single product.