Abstract
Ocean wave image data obtained by ERS-1/AMI (image mode) are analyzed in this study. Ocean
wave directional spectrum and other ocean wave parameters are derived by using fast Fourier
transform (FFT) and a series of modulation transfer function (MTF) corrections. The instrument
modulation transfer function (IMTF) is estimated by the least square fit method in the range and
azimuth direction separately. The significant wave height is estimated based on the azimuth smearing
effects and compared with buoy data. Finally the integral of ocean wave directional spectrum derived
from ERS-1/AMI data is compared with buoy data and the results of numerical predication. The
difference of the spectrum in the high frequency range are considered to be due to the azimuth
attenuation or noise removal during data processing.