Multifrequency, Multipolarization External Calibration of the SIR-C/X-SAR Radars

Anthony Freeman; K Sarabandi

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NASA NTRS · 19980015286

Multifrequency, Multipolarization External Calibration of the SIR-C/X-SAR Radars

Anthony Freeman·K Sarabandi

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Abstract

Progress and the future plans for the following objectives are discussed: (1) Assess the accuracy at which the SIR-C/X-SAR standard data products can be calibrated through the use of ground calibrators to estimate the end-to-end system polarization calibration constants (or distortion parameters) and incorporate the constants into the data processing; (2) Study the cross-calibration between three multipolarization systems: SIR-C, the National Aeronautics and Space Administration/Jet Propulsion Laboratory (NASA/JPL) DC-8 SAR, and the University of Michigan ground-based polarimetric scatterometer; (3) Evaluate the calibration "stability" of SIR-C/X-SAR (measured by variations in the calibration constants) over the range swath width and over a specified distance in azimuth. Variations over a 12-hour period (between ascending and descending passes) will also be studied; and (4) Develop a cost-effective calibration plan including development of inexpensive polarimetric active calibrators.

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Anthony Freeman, K Sarabandi. 1996-04-01. Multifrequency, Multipolarization External Calibration of the SIR-C/X-SAR Radars. https://ntrs.nasa.gov/citations/19980015286

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