Clutter Modeling And Simulation Of SBR For Natural Sence

Spaceborne radar(SBR) plays a more and more important role in the modern production and living, it overcomes the disadvantages of radar, shipborne radar and airborne radar. And it works on any day with large detecting space and can provide a relatively long time before warning. So it plays an irreplaceable role in civil and military area.While SBR has lots of problems to solve, one of which is its clutter from the ground is mach complex than airborne and shipborne radar. We know that the electromagnetic wave from SBR will cover a huge area on the ground or sea, resulting in lots of clutter. At the same time, the radar platform and the earth are moving very fast at any time, which will cause doppler effect. The bigger of wave footprints is, the more the interference sources of radar are. So it is much necessary to solve SBR clutter, for find the target which is hiding in the signals polluted by the clutter. The main research about this problem includes establishing the model and simulate of the SBR clutter. We must know that the research of the ground or airborne radar have the same or similar problem with SBR, but there are also many different places mainly caused by the characteristics of SBR itself.The major research of this dissertation is establishing the model and simulating the SBR clutter. We take method of using the general relationship between the radar echo and the transmitted waveform, and then we can found the clutter model with the actual area covered. The specific data used in simulations such as the earth’s rotation data, elevation data object properties, are supported by the geographic information system(GIS); and the other data such as clutter backscattering coefficient, the doppler frequency shift, the gain of the antenna are supported by the SBR itself. The main works are as follows:Firstly, we elaborate the significance of clutter simulation of SBR and the previous work. We introduced the commonly used simulation methods, the probability distribution of the clutter, and we discussed the advantage about this clutter model based on GIS;Secondly, we describe the key parameters involved in this study through calculation and mapping, these parameters include satellite platform parameters, the beam parameters, the irradiated area parameters etc;Thirdly, we will establish a SBR clutter model, using the grid mapping method. In this model, we will divide the actual area of the radar beam irradiation into blocks, and then calculate the various parameters of the clutter patches;Fourthly, we will simulate the final clutter. In this simulation, we use the radar equation, deduce the relationship between the blocks’ mall signals and transmit signal, and simulate the clutter based on actual ground;Fifthly, we analyze and summarize the performance of our clutter, and discuss the existing problems.