I am working on glacier studies and aim to generate a contemporary DEM of my Area of interest (AoI) which is located in mountainous region of Himalaya. DEM generation with Sentinel-1 Tool is an effective document for DEM generation but for my AoI its hard to find data with high coherence which is most important for DEM generation according to said document. May I seek any guidance to develop DEM of a high accuracy even with low coherence using SLC data of S1.
the most favourable conditions are short temporal baselines and large perpendicular baselines.
Use the ASF Baseline tool to find an image pair with 6 days and > 150 m.
Also, it is often worth comparing results from ascending and descending products.
You can share your AOI and I can have a look.
Thanks for feed back, I used ASF baseline tool. Problem in that have to stick with summer season i.e July 15-Oct 15. I searched all the required scenes. I do have minimum base line with 12 days interval and 150 perpendicular. But for those scenes I am unable to have an over all a good coherence.
I just want to know that " Is it any way to generate DEM even with low coherence.
I have another limitation that is unavailability of S1B data for my AoI. I am enclosing shape file in a zip folder of my AoI for your consideration. I will thankful if you help be to resolve the limitation of Data for my AoI Hunza Boudary.rar (23.5 KB)
Low coherence indicates decorrelated phase. You need the phase information for the estimation of topography.
Have you tried these two:
They have 153 m baseline
I just downloaded the scenes and working on these but I am not confident to get good results. However, I will share the results in a while. May I seek you help to find topography using phase information plz
I’m afraid I cannot overcome the laws of physics either
Let’s put it like this: If it would be easy to derive elevations from Sentinel-1 - why hasn’t there been any officially released S1 DEM so far? Don’t put too much hope in it.
You are right, but our struggle is to meet target with limitations. S1 has potential to drive DEM for contemporary period with rest of data set used in research. In my case I observing optical data of Landsat 8 for months of July to Oct for glacier region and I want to see the topography at that time.
I wish you good luck that the areas which are relevant to you have good coherence. But even then, unwrapping is challenging, because it will not poperly work on isolated areas of high coherence. There should be a connection over the image at least,