Research On3D Imaging Algorithm Of Bistatic-based Two Linear Arrays SAR

The bistatic-based two linear arrays3D (three dimensional) imaging SAR system is a system in which a linear antenna array is mounted in the cross-track direction of the transmitter and receiver respectively and the two platforms move with constant velocity vectors. Combining the pulse compression technique, it reconstruct the3D information of the imaging scene by the virtual2D antenna array which is synthesized by the antenna arrays placed in the cross-track direction of the transmitter and receiver and the linear movement of the two platforms. This technique opens up a new way in the bistatic3D imaging SAR technology.Bistatic Synthetic Aperture Radar system has such advantages:abundant information of objective, long operating distances, strong anti-interference and so on. The bistatic-based two linear arrays3D imaging SAR system inherits the merits of the bistatic Synthetic Aperture Radar system. It is suitable for the imaging of the complex scene and dangerous scene. Thus, it plays a very important role in civil applications (topographic mapping, ocean observation, disaster prediction, crop assessment and so on) and military applications (battlefield reconnaissance, target recognition and so on).This paper researches the imaging algorithm of the bistatic-based two linear arrays3D imaging SAR system. Firstly, we introduce a kind of2D (two dimensional) imaging algorithm of bistatic SAR working in invariant moving route pattern based on the implicit spectrum decomposition, namely BRM (BRM:Bistatic Range Migration) algorithm, and the characteristics of the algorithm are analyzed.Secondly, the structure characteristics of the bistatic-based two linear arrays3D imaging SAR system is introduced. We formulate the specific strategy of sending and receiving signal demonstrate the feasibility of the scheme. We analyze the spatial resolution of the system and introduce the method of applying the universal BP (back projection) algorithm in this system. Then a new bistatic SAR3D imaging algorithm, namely the back projection algorithm based on the Bistatic Range Migration (BRM-BP), is presented combining with the characteristics of BRM and BP algorithm and the feature of the system working in the strategy of sending and receiving signal present in this paper. The new algorithm first uses the BRM algorithm to map2d image of the echo, and then analyze the peak feature points of the imaging result and preliminarily position the existing space for all the objectives. Finally, we conduct the accurate3d imaging in these spaces by means of the BP algorithm.Lastly, the characteristics of the BRM and BP algorithm is verified by using MATLAB simulation. The simulation proves the feasibility of the BRM-BP algorithm and draws some useful conclusions.