First, I encountered an issue during my analysis. I came across a piece of code on GitHub, as shown in the figure below. This code directly used the SLC (Single Look Complex) data processed by SNAP to perform complex conjugation and subsequently calculate coherence. However, the complex conjugation computed directly from the SLC did not account for the compensation of flat ground and terrain phases. Therefore, I would like to inquire whether the SLC obtained through SNAP processing has already removed the effects of terrain and ground phase. Additionally, I would like to ask about the storage format of the SLC data obtained via SNAP processing: is it stored as an integer (int) or as a floating-point number (float)?
@jun_lu can you help?
In SNAP, there are two operators under Radar > Interferometric: Coherence Estimation and Interferogram Formation. In these operators, user has options to select “Subtract flat-earth phase” and “Subtract topographic phase”. In both cases, the coherence or the interferogram is saved in Float32.