摘要
针对传统DMFT类算法存在数值振荡问题及由此产生的"Bad Alpha"现象,提出了一种基于二阶差分的前后向DMFT算法——组合区间算法,分别构建前向和后向二阶辅助函数,对求解出的收敛区间进行重新组合,消除盲点,从而使数值振荡减弱,改善"Bad Alpha"现象。同时,基于组合区间算法,分别给出了标准大气、蒸发波导下的修正折射率和传播损耗分布曲线,计算结果是在动态粗糙海面的基础上得到的,显示出良好的稳定性,为粗糙海面条件下蒸发波导环境中雷达盲区探测等工作提供了一定理论基础。
Due to the problem of values concussion and the phenomenon of ＂ Bad Alpha＂ in traditional DMFTs, an improved forward-backward algorithm of DMFT based on second-order differential the algo- rithm of interval combination is proposed. In the algorithm, it constructs second-order auxiliary functions forward and ones backward, regroups convergence zone and eliminates blind spots in order to improving the phenomenon of ＂ Bad Alpha＂. Meanwhile, refractive index and propagation loss in the standard and evapo- ration-duct conditions are given. The results are calculated in the condition of rough surface which shows good stability, which provides a theoretical basis for the detection of blind spot of radar.
出处
《中国电子科学研究院学报》
2013年第5期486-490,共5页
Journal of China Academy of Electronics and Information Technology
基金
“泰山学者”建设工程专项经费资助
关键词
抛物方程
组合区间
蒸发波导
传播损耗
parabolic equation
interval combination
evaporation duct
propagation loss
