A spaceborne synthetic aperture radiometer simulated by the TUD demonstration model

The TUD synthetic aperture radiometer demonstration model consists of a 2-channel X-band correlation radiometer with two horn antennas and an antenna mounting structure enabling the horns to be mounted in relevant positions within a certain aperture. The cross correlation of the signals from the 2 antennas produces a sample of the visibility function, which is the Fourier transform of the brightness temperature distribution of the target area. A total aperture synthesis is obtained by sequentially placing the two antenna elements in all required pairs of positions and measure the corresponding samples of the visibility function followed by an image reconstruction procedure which is based on the inverse Fourier transform. The system has been used to simulate a spaceborne instrument (MIRAS) in order to validate the image reconstruction processing