| Space-borne radar, which can be used to detect and track the target in a large range, and it is not subject to the restrictions of the airspace and the area. It plays an important role in the field of battlefield reconnaissance, high precision mapping, resource exploration, environmental monitoring and other military and civilian areas. So it is the focus of the research of radar in recent years. Since space-borne radar usually works in the downward-looking, the clutter environment is very important to the performance of radar. The clutter of ground and sea, and weather clutter are important to the performance of radar. In order to improve the radar signal processing performance, it is very important that modeling the clutter accurately.Based on the background of the actual projects, this thesis studies the modeling method of the space borne radar clutter. Including the analysis of the clutter modeling method of space-borne radar, ground and sea clutter scattering coefficients, the effects of the ionosphere effects. Clutter modeling based on the statistical distribution model of the clutter modeling method based on the actual scene of the elevation DEM data. In this thesis, the following work has been done:1, Orbit design and modeling of satellite borne radar is given, and the simulation is carried out. Then the six coordinates system and their mutual transformation relationship are analyzed. Finally, the orbit model is established, and the position and velocity of the satellite at the special time are obtained.2, Statistical characteristics of the ground sea clutter and the related characteristics are studied, and the main characteristics of the distribution and correlation characteristics are introduced. Then the method of generating the different distribution characteristics of the clutter is studied. Then with the characteristics of space borne radar, we analyses the calculation method of multi-channel radar direction diagram, the sub satellite coordinates and the satellite position, and then draw the radar clutter, and gradually, the simulation results are given, Then the clutter modeling process is given.3, Characteristics of the satellite borne radar clutter are studied, and the influence of the earth rotation and the ionosphere is analyzed, and the simulation results are given. At the same time, a simple introduction about the processing method of the refraction effect in the actual clutter modeling is made. |
