Hello! Tell me the critical value of the Doppler centroid for interferometric processing?

Well, 100% overlap of Doppler-spectrum (identical Doppler centroid) is the ideal situation, and with less overlap the performance degrades. What data are you using?

Before interferometric processing, I need to know the difference between the Doppler centroid positions in the Stack Overview menu and the value of the Delta fDC [Hz],is responsible for this, if I understand everything correctly. What is the maximum value of the Delta fDC [Hz] for the construction of an interferogram? Because if the value of the difference in the positions of the Doppler centroid is greater than a certain value, then the interferogram will be built incorrectly.

The doppler centroid difference in negligible for S-1, you don’t have to worry about it at all.

For any images obtained with Sentinel-1A and Sentinel-1B?

Yes.

With ERS-2 ZGM (Zero Gyro Mode) data for example it’s another story.

Thank you so much!

Tell me please, what does it mean when the value of Bperp is negative? And what is the parameter Height Ambg?

Positive/negative depends on how the coordinate-system is defined and whether the 2nd orbit is “above” or “below” the 1st one. Height ambiguity tells you how much elevation corresponds to 2π = one phase cycle (this depends on baseline-length).

Thank you very much, you helped me a lot!