Terrain Matching Algorithm In The Tf / Ta And Simulation Study

The paper introduces several algorithms of terrain matching system and makes simulation study on the condition of Terrain Following/Terrain Avoidance.Firstly, the conception and performance of the terrain matching are discussed. The two-dimensional statistical model of terrain is described by planar non-stationary random process and function W-M in Topography. On the basis of the statistical model of terrain,the simulated digital maps are produced by computer. The principle , antenna and some problems of terrain mapping Radar are described. Two origins of terrain data and digital simulated radar model have been fused.This paper also discusses theories , characters , applications of the three following algorithms of terrain matching system: Terrain Contour matching (TERCOM), terrain-aided inertial navigation system, wavelet transform, the simulation results are provided. Generally speaking, the algorithm of Terrain Contour Matching is adapted to be used in cruise missiles which made fight path prior for that this algorithm is not a real-time system for it makes use of historical terrain data. While Kalman filter algorithm is a real-time , rapid calculation system. Which is appropriate for pilot or pilotless aircraft. Wavelet transform only decompounds the terrain data into high and low frequency data, but it decrease the amount of calculation for terrain matching algorithm effectively. In essence, it is a comparability measurement algorithm too.Thirdly, the paper analyzes the terrain entropy in detail. The primary bug of this algorithm is that discards the relative position information of terrain data and normalized processing. Based on this, the Kalman filter for optional estimation is offered and the Maximization of mutual information is synthesized, the performance of algorithm is improved, the filter divergence is restrained.At last, finished the software of the Terrain Matching in Borland C++ .