Modeling And Simulation Of The Former As The Dual-based Sar Imaging Algorithm

As a special mode of synthetic aperture radar (SAR), bistatic forward looking SAR (BFSAR) system can break through the limitations of squint mode SAR on forward-looking imaging. High resolution imaging in the right ahead flight direction is able to be realized under this mode. For the target is in the ahead of the receiver, BFSAR has many specialists in its space resolution, as well as the imaging principle.The study of bistatic forward-looking SAR imaging stands on the international foreland aspects. As an emerging SAR technology, bistatic forward-looking SAR has been applied in civilian and military fields. In this dissertation, the dissertation thoroughly studies on the bistatie forward-looking SAR system performance and imaging algorithm. The main contents of this dissertation are as follows:1. System performances of bistatic forward-looking SAR are investigated, including geometry mode,range history, Doppler characteristic and echo mode. The possibility of bistatic forward-looking SAR imaging is proved.2. Both range and azimuth resolutions of bistatic forward-looking SAR are analyzed. The flight mode under which the system can get its best azimuth resolution is proposed.3. One method of processing the bistatie forward-looking SAR signal as a monostatic squint SAR signal is proposed. The limitation and the error of this method are investigated.4. Based on the method of processing the bistatie forward-looking SAR signal as a monostatic squint SAR signal, an imaging algorithm named Chirp Scaling (CS) algorithm is proposed. The feasibility of this algorithm is demonstrated by the simulations.5. In term of reducing the error of the range history Taylor expansion approximation, as well as the second range range walk Correction, an imaging algorithm named nonlinear Chirp Scaling (NLCS) algorithm is proposed, which is based on the method of processing the bistatie forward-looking SAR signal as a monostatic squint SAR signal. The validity of this algorithm is demonstrated by the simulations.