@ABraun Thank you
Ya i need backscatter for each polygon. Will try in QGIS.
Is it correct method to use Geo-Tiff images to extract backscatter in QGIS? Earlier we used .dim format in SNAP to extract values.
no need for conversion to GeoTIFF, you can directly open the img files in the data folder of each product in QGIS.
@ABraun We got zonal statistics - (Mean) using QGIS but the values are in decimals like 0.0210, 0.0328… whereas we used to get -20, -15 back-scatter values form SNAP software. Why is this difference? We used Sigma0VH image. Are we missing anything?
db images are probably virtual only. You see this indicated by the v in the symbol of each band. Right-click your db images > convert band. Then File > Save product. They will then be physically written in your data folder as well and are available for use in QGIS.
We receive 2 strips for our project area, when we do SAR mosaic pixel values are changing from original to mosaic… How to solve this?
The process which we follow is
this is caused by resampling because both rasters need to be aligned to a common pixel spacing. Use Nearest Neighbor resampling instead of Bilinear if you want to maintain the original pixel values.
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@ABraun Thank you it worked. Pixel values change by 0.1. .
While doing Terrain- correction we are using Bilinear , does it make difference in the process?
and
Are we missing anything in the process which i mentioned earlier because when is see other posts i see Slice assembly and multi-looking is been used.
resampling always slightly changes the values, unless you select nearest neighbor.
Your graph looks fine but I wonder why you reproject the image while you can define a coordinate reference system in the terrain correction step already.
In Terrain correction Default projection is maintained
In Re-projection we are using
Without re-projection I am not able to do zonal statistics. There is a projection difference.
it should actually work to select UTM 44N directly in the terrain correction step…
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Ok Thank you will try that. Slice assembly and multi-looking is it required?
no. Your mosaicing replaces the slice assembly and multi-looking was already performed on GRD data.
Don’t just follow recipes, have a look at the single steps and test the effect of different tools whenever you are uncertain if need them or not 
Only you know what product you need in the end and for which purpose.
Thank you. I saw product details. Its mentioned that these things are already taken care. But i wanted confirmation from experts so that I don’t miss any steps.
This analysis is for agriculture plots.
Thanks once again for help.
that is totally legit 
A new publication on rice production mapping based on Sentinel-1 data.
I have seen the all the links which you provided here,but I didn’t get any procedure to do the process sir please help me to do the process of agricultural monitoring and yield estimation using SENTINEL 1 DATA.
Thanks in advance.
I’m afraid, there is no step-by-step guide. The signatures of crops can be different, depending on the geographic area you are working in. Consequently, their identification relies on observations, field measurements, empirical findings, and the expected yield is a matter of growing conditions.
SNAP doesn’t have a tool which you simply run and retrive a correct map for any part of the world.
The procedure, however, is quite similar for many cases. Either classification, time-series analysis or regression of a dependent variable based on SAR backscatter. Please have a careful look at the suggestions in this post.
Once you developed an idea, feel free to ask for opinions. But for such complex topics, no ready-to-use algorithms exist.
Two further resources by the EO college:
https://eo-college.org/resources/agriculture/
https://eo-college.org/resources/agriculture_tutorial/
hi sir,
I have done the time series analysis for my study area and I got the back scattered signatures also, but the thing is sir I’m getting difficult to interpret the entire image. sir please help me how can we interpret the images and which based we have to interpret.
sir I got this image, how can i interpret this please help me sir.
many thanks in advance.