For optical satellites GSD can be calculated by using this formula (Height * Pixel dimension/ Focal Length) but in case of SAR satellite high beam is used for imaging instead of optics. I just need to understand how to calculate GSD in case of SAR satellite different scanning modes.
The Ground Sampling Distance (GSD) is the distance between two consecutive pixel centers measured on the ground. The bigger the value of the image GSD, the lower the spatial resolution of the image and the less visible details. The GSD is related to the flight height: the higher the altitude of the flight, the bigger the GSD value.
For SAR data the GSD is mentioned in the metadata file of that data.
Actually it is radar cross section.
The radar cross section depends upon the 1.wave frequency, 2. the geometrical structure of of the ground object, 3. wave polarization, 4. the dielectric property of the ground object, 5. image configuration (i.e.- incident angle and scattering angle).
Dear Shahid Iqbal in SAR GSD can be interpreted as pixel spacing which is the distance between adjacent pixels in an image, measured in metres. For SAR imagery this Pixel spacing can be derived using rg x az (range and azimuth). This information is avaailabe within the metadata of SAR product.
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