Radar coordinates

Good afternoon everybody,

I would like to ask you a question, in case someone can help me. Do you know any method of estimating radar coordinates with SNAP? I have tried to get it with Pin, but can’t understand what it is. Also, I appreciate if you can tell me if there is another method in which I can obtain these coordinates for a certain area.

Thank you very much in advance

The pin manager allows you to place a pin on one or many pixels and extract both the value and coordinates of this pixel. One of many explanations available online: https://www.youtube.com/watch?v=5znAQH6vrLs

But you have to note that the coordinates of SLC and GRD products are only estimated. The actual position of a pixel within the image is distorted by various terrain effects. If you want to have precise geolocation information you have to execute both Apply Orbit File and Range Doppler Terrain Correction (at best with SRTM 1Sec). The latter tries to remove the topographic distortions based on a digital elevation model.

What exactly is your application? Maybe we can help you better if you tell us what you need these coordinates for.

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Thank you very much for your answer Abraun. I am sorry for the late response, but with the current situation, I have connection problems.

My question about the radar coordinates is just out of curiosity, because I have seen a book where they were mentioned, but nothing in particular. It was to compare the coordinates between acquisitions.

Thanks in advance.

No need to apologize.
If you want to compare backscatter at selected pixels of multiple images over time, you should apply radiometric calibration to each image and then use coregistration to merge them in one stack. This allows you to use the time series tool as described here: SAR Time-series Analysis tool"

Feel free to ask more questions if this does not help you.

Thank you very much for your response Abraun, it was very helpful and I am sorry for the late response.

Best regards.