Adaptive S filtering method for UAV height fusion estimation

A measurement of the UAV's height obtained by single sensor is usually not accurate and easily disturbed. A method of adaptive S-filter for height information fusion is developed to solve the problem. Firstly, an adaptive S-filter is designed to deal with the noise existed in the original data from the sensor. Secondly, the statistics is made on energy amplitudes of each frequency in the corresponding time, in which the energies whose sums are higher than 97% of the sum of total energy are kept. The noise can be effectively eliminated after S-inverse transform. Thirdly, an entralized Kalman filter is used to smooth the data and the height information of UAV can be obtained. The simulation experiment shows that our method of fusing the denoised height data by adaptive S-filter is more accurate than that obtained by wavelet, whose root-mean-square error is 26.3% lower.