Mapping tree height of mangroves using sentinel 1 (RADAR)

I am a Masters student and my research is based on mapping the tree height and biomass of mangroves using sentinel 1 (RADAR).
I am facing challenges in getting the real methodology on mapping the tree height and articles are so scarce on that matter especially on Radar data.
Can you kindly assist?

Let’s start with your second demand, which is

It is possible to calculate the Radar Vegetation Index, RVI, this topic is quite discussed in here, and how could be modified the equation,

Radar Vegetation Index

Radar Forest Degradation

Also you could take a look at

Agricultural Applications with SAR Data

Crop type classification

Also it is possible to classify S-1 images (GRD)

LAND COVER MAPPING USING SENTINEL-1 SAR DATA

DEFORESTATION MONITORING WITH SENTINEL-1 Case Study: Paraguay, 2018

Let’s comeback now to your first demand

It is not possible to measure the tree heights using S-1 for a very simple reason that S-1 is C-band 5.8 cm wavelength

Source

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@falahfakhri thank you for your import. so what can i do now to measure the tree height

in my opinion, this is a quite ambitious topic for a master thesis, especially if there is no experience in this area.
The problem is that Sentinel-1 signals decorrelate over vegetation quite quickly. Therefore, interferometric measurements of vegetation are hardly possible. I don’t think this can be done in SNAP, because the standard tools (classic interferometry) don’t allow this kind of analysis.

You could have a look at the PolSARpro toolbox which was designed for biomass analyses. But I don’t know if dual polarization data (Sentinel-1 has only VV+VH) can be used for forest height inversion.
https://www.ietr.fr/polsarpro-bio/

At least there are examples within the program on this topic.

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I think you could try up airborne LIDARSACAN or Laser scan, this is explained in here, of course in case you have this capabilities,

ACCURACY OF MEASURING TREE HEIGHT USING AIRBORNE LIDAR AND …

The other scenario you could use ALOS PALSAR, L band,

L-Band SAR Backscatter Related to Forest Cover, Heightand …

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you might also want to have a look at the ESA Polarimetry Course materials (January 2019), especially on the tutorials on forest height inversion:

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thank you so much

Dear MissGee,
I am writing my doctor thesis about this topic and I dont think it is feasable in the context of a master thesis. Especially S-1 data is not useable for this aproach since the temporal baseline between two timesteps (you need for creating an interferogram) is too long. The temoporal decorrelation over forest/trees or mangroves is just too bad. You can use a coherence optimization approach to get a better coherence but in my example areas the results were still too bad to calculate tree hight. I tried it with SNAP, PolSARpro and also ERDAS Radar Toolbox. As @ABraun was mentioning the dual-pol data of S-1 is also an issue in PolSARpro.
If you are still interested in doing this topic have a look in random volume over ground or random motion over ground models.
All the best

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thank you so much for your assistance. can i work with getting canopy height and then subtract DEM to get tree height in this case?

Yes, this would be the overall plan, first getting the canopy height from the inversion models (for example random volume over ground) and than subtracting a DEM.

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