基于基尔霍夫近似的改进分形海面电磁散射特性  

Characteristics of Electromagnetic Scattering from Improved Fractal Sea Surface Using Kirchhoff Approximation

作　　者：陈瑜[1] 胡云安[1] 马国欣[1] 李海君[1] 

机构地区：[1]海军航空工程学院控制工程系,山东烟台264001

出　　处：《战术导弹技术》2012年第6期94-99,共6页Tactical Missile Technology

基　　金：军队科研基金资助项目

摘　　要：针对经典分形模型的功率谱在空间波数小于基波波数时不能满足正幂率的问题,提出了一种统计模型和归一化带限Weierstrass分形模型相结合的一维粗糙海面模型,确定了功率谱的闭式解,并且和JONSWAP谱进行了比较,两者吻合较好。在满足Kirchhoff近似的条件下推导改进模型电磁散射系数的闭合解,对统计模型、经典分形模型和改进模型的非相干散射强度系数的角分布进行了比较,具体分析了不同尺度因子、不同分形维数、不同入射频率和风速下改进模型非相干散射强度系数的角分布情况。Aiming at the problem that the omnidirectional sea-wave spectrum of fractal sea-wave model could not satisfy the positive power law when spatial wave numbers were smaller than the fundamental wave number,1-D sea-wave model was proposed by combining statistical sea model and normalization band-limited Weierstrass-Mandelbrot（WM） fractal sea model.With the proposed method,the closed form expression of the omnidirectional sea-wave spectrum was calculated,and omnidirectional sea-wave spectrum is in good agreement with the common spectrum of JONSWAP.Electromagnetic scattering coefficient of improved model based on the Kirchhoff approximation was derived.The angular distributions of the incoherent scattering intensity coefficient of statistical model,classical fractal model and improved model were analyzed,the angular distributions of incoherent scattering intensity coefficient of improved model was compared based on different fractal dimension,frequency and scale factor,frequency and wind speed.

关 键 词：分形模型 海谱 统计模型 电磁散射 

分 类 号：TN011[电子电信—物理电子学]