A Parametric Algorithm to Retrieve Ocean Wave Spectra from Interferometric Synthetic Aperture Radar

A new ocean wave retrieval method for the along-track interferometric synthetic aperture radar (ATI-SAR) phase image is presented. The new algorithm, named parametric retrieval algorithm (PRA), uses the full nonlinear mapping relations as proposed by He and W. Alpers (2003). It differs from previous retrieval algorithms in that it does not require
a

priori
information on the sea state and also calibration of the ATI-SAR phase image. The advantage of PRA is that it jointly retrieves information of wave parameters and wind speed. The method has been validated by collocating two X-band HH-polarized ATI-SAR phase image and one C-band HH-polarized ATI-SAR phase image spectra with spectral buoy measurements. The wave parameters and wind speed estimated from PRA are in agreement well with buoy observations. The proposed method can be employed by future satellite missions such as TerraSAR.