Aeromagnetic interference could not be compensated effectively if the precision of parameters which are solved by the aircraft magnetic field model is low. In order to improve the compensation effect under this condit...Aeromagnetic interference could not be compensated effectively if the precision of parameters which are solved by the aircraft magnetic field model is low. In order to improve the compensation effect under this condition, a method based on small signal model and least mean square(LMS) algorithm is proposed. According to the method, the initial values of adaptive filter's weight vector are calculated with the solved model parameters through small signal model at first,then the small amount of direction cosine and its derivative are set as the input of the filter, and the small amount of the interference is set as the filter's expected vector. After that, the aircraft magnetic interference is compensated by LMS algorithm. Finally, the method is verified by simulation and experiment. The result shows that the compensation effect can be improved obviously by the LMS algorithm when original solved parameters have low precision. The method can further improve the compensation effect even if the solved parameters have high precision.展开更多
Rafael C. Gnzalez has mentioned an algorithm on adaptive local noise elimination filter in the book named Digital Image Processing. This paper points out the algorithm's deficiency and presents an improved harmonic m...Rafael C. Gnzalez has mentioned an algorithm on adaptive local noise elimination filter in the book named Digital Image Processing. This paper points out the algorithm's deficiency and presents an improved harmonic mean filter algorithm which makes mean square error emse cutting quarter but SNR, SNPm and PSNR increasing a tenth more than original algorithm. This filter algorithm is verified to be effective by simulation experiment.展开更多
基金co-supported by the National Basic Research Program of China (No. 623125020103)
文摘Aeromagnetic interference could not be compensated effectively if the precision of parameters which are solved by the aircraft magnetic field model is low. In order to improve the compensation effect under this condition, a method based on small signal model and least mean square(LMS) algorithm is proposed. According to the method, the initial values of adaptive filter's weight vector are calculated with the solved model parameters through small signal model at first,then the small amount of direction cosine and its derivative are set as the input of the filter, and the small amount of the interference is set as the filter's expected vector. After that, the aircraft magnetic interference is compensated by LMS algorithm. Finally, the method is verified by simulation and experiment. The result shows that the compensation effect can be improved obviously by the LMS algorithm when original solved parameters have low precision. The method can further improve the compensation effect even if the solved parameters have high precision.
基金This project is supported by National Natural Science Foundation of China (60473024) and the Natural Science Foundation of Zhejiang Province(603009)..
文摘Rafael C. Gnzalez has mentioned an algorithm on adaptive local noise elimination filter in the book named Digital Image Processing. This paper points out the algorithm's deficiency and presents an improved harmonic mean filter algorithm which makes mean square error emse cutting quarter but SNR, SNPm and PSNR increasing a tenth more than original algorithm. This filter algorithm is verified to be effective by simulation experiment.