Research On SAR Signal Simulation And Imaging Algoithm

Synthetic aperture radar (SAR) is a new kind of radar techonology, in which a theoretical wider antenna is built through signal analysis techniques to obtain a fine azimuth resolution. It can work all-time and all-weather, and can penetrate some shelters with imaging and map with the advantage of far from the swath, so SAR is widely used in military fields and some areas of national economy as geological exploration, topographical mapping, ocean studings and so on, developing very fast.The paper firstly gives a brief description to the principle of SAR imaging and analyses the principle of fine azimuth resolution. Secondly, provides the simulation of one-dimentional and two-dimentonal signal models and studies the characters of chirp signal. Thirdly, imaging results of different macthed filtering devices and RCMC modes are evaluated and compared, discovering that the result will be optimal if RCMC is achieved with sine interpolation or linear phase shift method in frequency domain. Forthly, caculates and analysis the focusing depth and puts forward some solutoins to deal with the defocusing when the target point is far from the reference point. And then, provides the simulation of RDA in zero squint case. Fifthly, analyses the principle of BPA, and derivates the key issues of carrier recovery, sampling and meshing in details. Following with the simulation of BPA and the evaluations of the results.At end of this paper, the BP imaging algorithm is applied in an ultra wideband through-wall radar system. The imaging results show the BP algorithm is achieved better effects than applied other imaging algorithms, especially in the aspect of imaging on slowly moving object.