I ve been making a report about Sentinel products, software, specifications… I ve been lately studyng the backscattering coefficient to understand calibration on SAR images. I understand the backscattering coefficient and its meaning. Moreover, looking for definition of some Sentinel products, I ve found this table that containts: (NESZ), Radiometric stability and Radiometric accuracy. However I dont understand them very well.
Does anyone here understand these three last parameters? I am looking for info to understand it, but if someone knows it would be very appreciated!
Thank you very much for all.
For the three quantities you mentioned:
(i) the radiometric stability is the standard deviation of the difference between the measured and nominal radar cross-sections from a temporal series of point target measurements. So for example if the radar cross-section of the same target were measured several times, then the standard deviation of the radar cross-section is given by the radiometric stability. The stability also applied to distributed targets assuming that the target itself does not change and there are enough pixels to accurately measure the radar cross-section.
(ii) the radiometric accuracy of a given point target is the mean difference between the measured and nominal radar cross-sections from a temporal series of point target measurements. This gives the accuracy with which the radar cross-section of either a distributed or point target can be measured.
(iii) the phase error is the requirement for phase during a 10 minute acquisition (I believe).
Measured values for radiometric accuracy and stability are given in the N-Cyclic Reports. Note that the radiometric stability is a 1sigma (one standard deviation) value rather than the 3sigma value given in your Table 1.
Hope this answers your question.
Thank you very much Peter! It s better understood now. Thank you so much.