Ionosphere Impact on Low-frequency Sar Signals
نویسندگان
چکیده
Ionospheric propagation effects have a significant impact on the signal properties of SAR observations, especially at low operation frequencies. Dispersion, group delay, Faraday Rotation (FR), and phase shifts are all a function of the socalled Total Electron Content (TEC), the operating frequency and the system bandwidth. In order to choose the right acquisition time with lower ionospheric impact, the TEC maps can be used to estimate the FR impact on a potential SAR mission, taking advantage on the periodicity shown by the ionosphere.
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