The Novel 3D Terrain Matching Navigation Algorithm Based on Contour Map and Fourier-Polar Transform
Guangjun Zhang · Journal of Astronautics · 2008
A novel 3D terrain matching algorithm is presented in this paper.Contour map is utilized to represent the real-time recovered terrain and the aircraft-borne referenced terrain,so the 3D terrain matching is converted to contour matching.Integrating Polar transform into Fourier transform resolves matching problem between real-time contour map and reference contour map,which had the following advantages: it doesn't need extracting features,instead it matches the two contour maps in the whole frequency domain which is rotation and translation invariability and is inherently insensitive to random noise and local distortion;Fourier transform is easily hardware realization and has certain superiority in practical application.In this method,intercept the same size map with the real-time contour map in the reference contour map at first,and then the matching of these two maps is carried out by the proposed algorithm which achieves the rotation and translation parameters to correct the flight attitude of aircraft.By way of theoretical analysis and sand-table simulation results,this algorithm is insensitive to noise and distortion,which also has the merits of high reliability and high accuracy,and has important reference value to the practical 3D terrain navigation system.