Modeling And Simulation Of Synthetic Aperture Radar Echo Simulator And System Design

As a new imaging technology, Synthetic Aperture Radar (SAR) imaging technology has evolved to satisfy a variety of application for both civilian and military users. Along with the increasing and extensive application of SAR, many fields such as design of SAR system, evaluating of imaging algorithms, or suppression of noise and clutter ask for more demands and higher quality of SAR raw data.SAR raw data simulation and the design of simulator have been generally studied in this dissertation, the main contents of the dissertation are as follows:1. First of all, high resolution principle of SAR, SAR echo theoretical model and several algorithms of SAR raw data simulation are introduced. Then RTPC (Range Time domain Pulse Coherence) is adopted to simulate SAR point target raw data, which is processed by RD algorithm and anticipant result is presented, so is point array targets.2. Adopting the theory of Kirchhoff approach and facet model, backscatter coefficient of distributed target is computed. Then the raw data of distributed target based on 2D FFT is simulated. Steps of simulation is given and characteristics of raw data are also analyzed in this dissertation.3. Based on the introduction of Gaussian sea surface model, a non-Gaussian model is discussed, which is a skewed surface. Then a modified two-scale model is introduced to compute the backscatter coefficients, which accounts for up/down wind difference. The variation of backscatter coefficients' amplitude along with polarization and incidence is analyzed. Finally a method of ocean surface raw data simulation is discussed, which is proved by simulation results.4. An implementation of SAR raw signal simulator is presented, including the function principle and hardware design of every part. Schematics and PCB layout are also carried out.