Sentinel-1, Ascending and Descending orbit

Does Ascending and Descending orbit data affect the quality of the backscatter coefficient in the data processing of sentinel-1?Thank you!

Basically the backscatter coefficient depends of many parameters of each orbit,

Generally physical parameters of the area, height, alignment, density, shape, and material of the objects in addition to the distribution of objects , as well as the incident angle. Relationship of co-polarized and cross-polarized backscatter, all of these parameters are affecting the backscatter,

But

This part of your question, ideally it should depends on the approach of your processing and the goal of study. I think it is difficult to say without a comparison of both Arc. and Desc. according to your approach.

Take a look at this please,
https://sentinel.esa.int/web/sentinel/user-guides/sentinel-1-sar/definitions

I agree with falahfakhri. Ascending or descending has an impact on the pixel area which is illuminated by the sensor and depending on the local incidence angle lead to differences in backscatter intensity. If your area is completely flat, this effect is minimized but theoretically, the sensor is still interactig with other parts of the surface.

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Thank you for your reply. Can I use the same day’s Ascending and Descending orbit data to analyze the effect of different local angles of incidence on the backscatter coefficient? I first assume that the soil surface is flat enough.If you have a good way to determine the relationship between the local angle of incidence and the backscatter coefficient, please let me know.Thank you!

Thank you for your reply. Can I use the same day’s Ascending and Descending orbit data to analyze the effect of different local angles of incidence on the backscatter coefficient? I first assume that the soil surface is flat enough.If you have a good way to determine the relationship between the local angle of incidence and the backscatter coefficient, please let me know.Thank you!

Answering your first question, I think yes, it is possible, because the orbit is different,

Concerning your second question,

Take a look at these posts, they explain the relationship between incidence angle and backscatter, further more explain, how to extract the backscatter and create the correlation,

Would be interesting, yes.

Hello,

Is there different Incidence angle range for Ascending and Desceding mode? Or range is same?

Also, I was trying to find out from which side of relative orbit is satellite monitoring the surface during the pass? Western or Eastern side?

Thank you!

Ascending and descendng are not modes but different parts of the orbit, so the incidence-angle range is the same. Sentinel-1 is right-looking all the time while some missions can image both sides of the orbit.

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Thank you! Mode is not a good term indeed.

Cheers!