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are equally spaced. Finally, system design engineers would choose β
o
values, as these values are
independent from the terrain covered.
γ
o
= σ
o
/ cos(incidence angle) (18.1)
β
o
= σ
o
/ sin(incidence angle) (18.2)
Radiometric stability is the standard deviation of the (time series) measurements of the radar cross-
section of a calibration target (using the same calibration constant) and the radiometric accuracy as
the (time series) average of the absolute difference between the nominal radar cross- section and the
measured radar cross- section (using the same calibration constant) of a calibration target.
18.3 TYPES OF SAR CALIBRATIONS
The measured radar backscatter is uniquely related ...