Across-track interferometric SAR imaging experiment with multi-carrier frequencies

In this paper, we introduce the recently carried out airborne experiment with a Ku band multi-carrier-frequency interferometric SAR system. This system can work at three carrier frequencies, i.e. f₁, f₂ and f₃ are 13.7GHz, 13.9GHz and 14.1GHz, respectively, each frequency channel has the same bandwidth of 220MHz. In the across-track experiment, very good interferometric phase images and mountainous topographies were obtained for three carrier frequencies. The recovered DEMs from three frequencies agreed with other very well. The obtained topographies of each carrier frequency agree with each other very well. Different filtering windows of 3, 5, 7 and 9 for denoising are applied to the interferometric phases and the corresponding DEMs are compared. It is shown that by combining the measurements of three frequencies, we can improve the accuracy of DEM without losing the spatial resolution.