| This article is composed of six parts. In the first part, the research progress of cloud motion wind was introduced and the significance of the 1-D Fourier analysis technique was given. In the second part, based on fluctuation theory and Fourier analysis, the one dimension Fourier analysis technique on cloud motion winds is deduced and demonstrated theoretically. By simulating mathematically on frequency and on space, we not only uncovered two questions in practice, first is phrase folding, second is frequency spectrum overlapping, but also gave methods and suggestions to solve them or avoid them. In the third part, we analyzed the relations not only between space average speed v andamplitude-weighted average speed v, but also between space speed variance σx and frequency speed variance σf. By comparing the relations, the practical meanings of vand σf in tracking cloud motion are found out. In the forth part, the system of cloudwind was introduced and the algorithms of tracking cloud motion with two sequential satellite images by the 1-D Fourier analysis technique was given. In the fifth part, we tracked cloud-motion of consecutive satellite images with one-minute interval by maximum correlation matching technique and the 1-D Fourier analysis technique. Compared with the data provided by Eumatsat, the velocities which are computed by the 1-D Fourier analysis technique are better than that computed by the maximum correlation matching technique. The directions got by two techniques are approximately uniform. In the sixth part, we summarized our research and put up with shortages of this article.
|
PDF Full Text Request