基于分形的粗糙海面三维抛物方程模型及其应用

Three-dimensional parabolic equation model for rough sea surface based on fractal method and its application

风驱海浪随机起伏变化是海面环境的典型特征之一,而较大的风浪通常会给海面无线通信带来重要的影响.传统的抛物方程(Parabolic Equationmethod,PE)模型在预测粗糙海面的电波传播时,未能充分考虑海浪的电磁散射以及阴影效应等.针对以上不足,文中基于三维抛物方程,引入动力学分形方法,对传统的抛物方程模型进行了改进研究.相比传统的Miller-Brown近似方法,改进后的预测模型能更好地反映出海浪几何特征对电磁波传播的影响.最后以舰载雷达的有效探测范围为计算背景,对粗糙海面的电波传播特性进行了仿真分析,结果表明了该模型在区域级海面环境电波预测的可行性.

Random variation of sea waves is one of the typical characteristics of sea surface environ-ment,and it will usually have an important influence on ocean communication system.The traditional par-abolic equation model fails to fully consider the electromagnetic scattering and the shadow effect of the sea waves when the electromagnetic wave propagation over the rough sea surface.Aiming at this problem,by introducing the dynamic fractal method,an improved model based on the three-dimensional parabolic equa-tion is proposed in this paper.The improved model is compared with the traditional Miller-Brown approxi-mation method,and the results show that the former can better reflect the influence of the geometrical characteristics of the sea waves on the radio propagation.Furthermore,the effective detection range of the shipboard radar is simulated,and the radio propagation characteristics over the rough sea surface are ana-lyzed,which shows that the proposed model is effective.