process for resolving an ambiguity in the determination of the angle of the antenna and the frequency dippler in a synthetic aperture radar

摘要

In a method for resolving ambiguity in the determination of antenna angle of view and Doppler frequency in synthetic aperture radar (SAR), by evaluating the dependence of the Doppler frequency on the transmitting frequency a skew of the two-dimensional Fourier power spectrum or the two-dimensional autocorrelation function of radar data is measured in that the radar data are subjected to a range Fourier transformation and for the individual range frequencies in a following Doppler centroid estimator a Doppler centroid determination is carried out in the azimuth direction. By this method the pulse repetition frequency ambiguities are eliminated without any demands having to be made on the data acquisition or a high image contrast; this method can therefore be applied to any region of the raw data matrix. Moreover, no azimuth compression is necessary.