Pixel average export fall in circular polygon mask

hi. how can i export average of pixels fall in the circular polygon in CSV or text for all bands and use results for regression. i have 166 field point plot with 18 m circular polygon for each point. when i perform export mask pixel in result i have 2000 pixel and it is not creat mean value for each field polygon .
with regards

If I understand correctly, you want to use a ROI (polygon) to extract a mean value of that area, right? The option you have within SNAP is to use the StatisticsOp processor in gpt mode, with your ROI input as a shape file.

Some hints on GPT:

Yes, Ana is right. The StatisticsOp is probably the right tool for you.
In this thread you can get some guidance:

thank for your guidance. i also can export values by raster -> export pixel and finally define window size and mean operator on pixels and export to text file and then importing to the excel.