Numerical study of electromagnetic scattering from one-dimensional nonlinear fractal sea surface  

作　　者：谢涛 何超 William Perrie 旷海兰 邹光辉 陈伟 

机构地区：[1]School of Information Engineering,Wuhan University of Technology [2]Bedford Institute of Oceanography,B2Y 4A2,Dartmouth,NS,Canada

出　　处：《Chinese Physics B》2010年第2期234-239,共6页中国物理B（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant No. 40706058);the National High Technology Research and Development Program of China (Grant No. 2007AA12Z170);the Science-Technology Chenguang Foundation for Young Scientist of Wuhan, China (Grant No. 200850731388);the wind and waves component of the Canadian Space Agency GRIP Project entitled Building Satellite Data into Fisheries and Oceans Operational Systems

摘　　要：In recent years, linear fractal sea surface models have been developed for the sea surface in order to establish an electromagnetic backscattering model. Unfortunately, the sea surface is always nonlinear, particularly at high sea states. We present a nonlinear fractal sea surface model and derive an electromagnetic backscattering model. Using this model, we numerically calculate the normalized radar cross section （NRCS） of a nonlinear sea surface. Comparing the averaged NRCS between linear and nonlinear fractal models, we show that the NRCS of a linear fractal sea surface underestimates the NRCS of the real sea surface, especially for sea states with high fractal dimensions, and for dominant ocean surface gravity waves that are either very short or extremely long.In recent years, linear fractal sea surface models have been developed for the sea surface in order to establish an electromagnetic backscattering model. Unfortunately, the sea surface is always nonlinear, particularly at high sea states. We present a nonlinear fractal sea surface model and derive an electromagnetic backscattering model. Using this model, we numerically calculate the normalized radar cross section （NRCS） of a nonlinear sea surface. Comparing the averaged NRCS between linear and nonlinear fractal models, we show that the NRCS of a linear fractal sea surface underestimates the NRCS of the real sea surface, especially for sea states with high fractal dimensions, and for dominant ocean surface gravity waves that are either very short or extremely long.

关 键 词：fractals NONLINEARITIES sea surface electromagnetic scattering 

分 类 号：O441.4[理学—电磁学] O415.5[理学—物理]