A new fast method for the reconstruction of 2-D microwave images of rotating objects

In this paper, the problem of microwave imaging of rotating objects is approached from a digital signal processing point of view, Attention is focused on the reconstruction of the two-dimensional (2-D) image of an object obtained by processing complex samples of the continuous wave (CW) signal return received for different object aspect angles covering a 2 pi total variation, The effects of a polar sampling of the Fourier transform (FT) of the target reflectivity function on the impulse response of the imaging system are analyzed, A criterion for the choice of the angular sampling interval in order to control the image blurring is given, Finally, a new and fast digital signal processing method for image reconstruction is proposed. This method reconstructs high resolution images of rotating targets illuminated by a CW electromagnetic signal or by a large bandwidth transmitted signal, This algorithm is suitable for processing wideband received signal of targets observed for a large variation of the viewing angle, so it is very attractive for the reconstruction of very high spatial resolution target images in SAR/ISAR systems, To show the performance of the method we finally present and discuss the results obtained by applying the proposed technique on simulated and experimental data.