Fully Focused SAR Processing for Radar Altimeter: a Frequency Domain Approach

In this paper, the full focused processing in the frequency domain for high Pulse Repetition Frequency (PRF) radar altimeter science data is proposed. Considering a radar altimeter as a Synthetic Aperture Radar (SAR) instrument operating in near nadir-looking geometry, a SAR frequency-domain focusing algorithm, namely Range-Doppler algorithm, is analyzed. Then a properly modified processor for radar altimeters is described and implemented. Simulation set-up using parameters from two missions (CryoSat and Sentinel-6) and a preliminary result from in-orbit CryoSat data confirm the effectiveness of the full focused processing in the frequency domain. The proposed approach, compared to the one formerly proposed in literature [1], is less complex and more computationally efficient.

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[4]  Alejandro Egido,et al.  Fully Focused SAR Altimetry: Theory and Applications , 2017, IEEE Transactions on Geoscience and Remote Sensing.