Terrain Clutter Modeling And Simulation Based On Fractal Theory

The clutter is caused by ground objects, sea and weather conditions. It has a great influence on the target detection performance of radar system. In this paper, the simulation of the ground clutter is accomplished by using the grid mapping methodbased on the radar coherent video echo model and DEM data.Firstly, this paperintroduces the structural characteristics of digital elevation model(DEM) data, and gets the DEM data of3 D emulation terrain by using the random midpoint displacement which is based on the fractal theory. According to the grid mapping method, it next establishes the facet model by using the DEM data and treats each facet as a clutter scattering unit.And then combined with the spatial position information of the radar, the grazing angle, radar cross section and other parameters are calculated in this paper.Secondly, the paper introducesthe nearest visible point-based algorithmand improves it according to the particularity of radar application. It can judge a scattering unit is visible to radar or not more quickly and effectively. Then the radar coherent video echo model is proposed in this paper. Based on this model, the coherent echo signal of the antenna main lobe is derived.Finally, the paper introduces the features and approaches of the MATLAB/C++ mixed programming. Then MFC software is accomplished by calling the dynamic link library(DLL) of the MATLAB program file. The whole software is composed of three modules: the simulation parameters input control, the simulation results and the simulation state,and realizes several functions including terrain modeling, shield processing and clutter simulation.