本书系统地介绍了近海面蒸发波导的理论模型与特性。全书共12 章，内容包括绪论、蒸发波导的基本概念、 蒸发波导预测模型、蒸发波导高度时空分布规律、蒸发波导环境特性实时监测及短期预报方法、蒸发波导与海水蒸发量的关系、蒸发波导中的电磁波传播模型、海洋蒸发波导中的电磁波传播特性、蒸发波导数据传输系统、蒸发波导反演方法、基于BP 神经网络算法的蒸发波导预测模型、蒸发波导环境特性数据库软件。本书融入了作者团队10 余年来在蒸发波导方面的科研成果，纳入了作者团队在国内外重要期刊上发表的20 余篇论文，同时也参考了少量国内外相关的研究成果。

前 言 随着我国建设海洋强国步伐的加快，对海洋气象环境认知、海上电磁信道模型与特性的需求日益旺盛。蒸发波导是近海面常见的一种大气波导现象，它对电磁波的重要影响，使它在海洋目标探测与侦察、海上通信与电子对抗、导航制导与控制、海洋科学研究、海洋环境监测、海洋开发利用等领域具有十分重要的科学研究价值，也具有特别重要的实际应用意义。本书涵盖通信工程、雷达工程、电子与信息工程、电子对抗、海洋工程、海洋环境等技术领域，书中大部分内容是作者团队10 余年来在蒸发波导方面的科研成果总结与提炼，纳入了作者团队在国内外重要期刊上发表的20 余篇基础研究论文。此外，书中也涉及少量国内外同行近年来取得的研究进展。 蒸发波导是因海水蒸发在近海面形成的一种天然的电磁波传播通道，当发射天线处在蒸发波导内时，电磁波能量被陷获在蒸发波导层中，路径损失大大减小。蒸发波导是一种固有的物理现象，时刻影响着海上雷达、通信、导航、电子对抗、侦察等电磁系统的工作性能。因此，准确揭示蒸发波导高度分布特征，对保障雷达、通信、导航、电子对抗等无线电系统性能至关重要。然而，人们对蒸发波导的认识还很粗浅，在蒸发波导理论模型及其特性的研究方面，可供参考的资料还不多。作者团队在长期的蒸发波导理论模型及其特性研究中，针对不同的环境条件和应用场景，开展了详细的理论研究和实验验证，取得了一些研究成果。本书系统地介绍作者团队在近海面蒸发波导方面的研究成果，希望同行参考借鉴并共同推动更加深入且系统的研究及应用。 全书共12 章，主要内容如下： 第1 章介绍蒸发波导及其相关的概念，以及研究的背景、意义、历史和现状。第2 章介绍蒸发波导计算基本公式、对流层折射和大气波导的分类等基本知识。第3 章介绍蒸发波导预测模型及大气学理论知识，包括大气运动的基本概念、PJ 模型、伪折射率模型、NPS 模型、蒸发波导高度对气象要素的敏感性分析、冷空气条件下不同蒸发波导预测模型的对比等内容。第4 章阐述蒸发波导高度的时空分布规律，包括蒸发波导统计分析的方法与数据源，世界海洋、西太平洋、中国南海、亚丁湾的蒸发波导高度时空分布规律及其实验验证等内容。第5 章阐述蒸发波导环境特性实时监测及短期预报方法，包括蒸发波导环境特性实时监测方法、基于GFS 数据和WRF 模型的蒸发波导环境特性短期预报方法等内容。第6 章阐述蒸发波导与海水蒸发量的关系，包括研究数据和方法、蒸发波导高度与蒸发量关系的定性分析、从蒸发量定量估算蒸发波导高度的方法等内容。第7 章介绍蒸发波导中的电磁波传播模型，涉及射线追踪模型、抛物方程模型、混合模型近海面蒸发波导理论模型与特性 等内容。第8 章阐述海洋蒸发波导中的电磁波传播特性，包括水平均匀蒸发波导中的传播特性、水平不均匀蒸发波导对电磁波传播的影响、海上障碍物对电磁波传播的影响、粗糙海面对电磁波在蒸发波导中的超视距传播的影响、海洋蒸发波导信道的多径效应分析及实验、蒸发波导信道的频率响应等内容。第9 章阐述蒸发波导数据传输系统的辅助决策方法，包括辅助决策的原理、蒸发波导数据传输系统的参数优化、蒸发波导数据传输系统的可通概率、海上实验验证等内容。第10 章介绍蒸发波导反演方法，包括蒸发波导反演的概况、利用电磁波传播路径损失反演蒸发波导修正折射率剖面、利用雷达海杂波反演蒸发波导修正折射率剖面等内容。第11 章介绍基于BP 神经网络算法的蒸发波导预测模型，包括基于BP 神经网络算法的蒸发波导建模基本原理、稳定与不稳定条件下的训练结果对蒸发波导模型的影响等内容。第 12 章阐述蒸发波导环境数据库软件，包括软件设计总体思路、海区网格选择功能模块、海区网格蒸发波导特性功能模块、全球蒸发波导特性功能模块、西太平洋蒸发波导特性功能模块、蒸发波导剖面预测功能模块等内容。 本书由西北工业大学团队撰写，具体分工如下：杨坤德编写了第1、2、3、11 章，史阳编写了第4、5、7、8、9、12 章，张琪编写了第6、10 章，杨坤德、马远良对全稿进行了审阅和修改，王淑文、杨帆等研究生对初稿进行了校对。书中纳入了作者团队在国内外重要期刊上发表的学术论文，也涉及作者团队所指导的多名研究生的少量研究成果，如闫西荡、潘越、朱明永、赵楼等的研究成果。同时，本书所反映的研究结果得到了多项国家级科研项目的支持，是在课题组长期科研工作基础上提炼而成的。西北工业大学的相关老师为此做出了重要贡献，包括肖国有、杨益新、孙超、何正耀、雷波、段顺利、韩一娜、王关峰、朱治富等老师。在此对国家与学校有关部门、有关老师和同学深表感谢！希望本书的出版对海上探测、海上通信、信号侦察、电子对抗、海洋科学、海洋工程、海洋监测、海洋开发等领域的科研工作者、教师、研究生和本科生有所帮助。 由于作者学识水平所限，书中难免存在不妥之处，恳请读者和相关专业同仁提出宝贵的意见和建议。 作 者 2022 年5月20 日

目 录 第1 章 绪论 ································································································.1 1.1 蒸发波导的研究背景与意义 ··································································.1 1.2 蒸发波导的研究历史和现状 ··································································.5 1.2.1 蒸发波导修正折射率剖面的测量方法和预测模型研究 ························.7 1.2.2 蒸发波导高度时空分布规律研究 ·················································.10 1.2.3 蒸发波导环境特性实时监测及短期预报方法研究 ····························.12 1.2.4 蒸发波导中的电磁波传播理论和传播模型研究 ·······························.14 1.2.5 蒸发波导对船载电子系统的应用影响研究 ·····································.16 1.3 本书的主要内容 ···············································································.16 本章参考文献 ·························································································.18 第2 章 蒸发波导的基本概念 ·········································································.24 2.1 对流层折射 ·····················································································.24 2.1.1 球面分层大气中的折射定律 ·······················································.24 2.1.2 射线的曲率半径 ······································································.25 2.1.3 折射的分类 ············································································.26 2.1.4 修正折射率 ············································································.28 2.2 对流层大气波导的分类 ······································································.29 本章小结 ·······························································································.30 本章参考文献 ·························································································.30 第3 章 蒸发波导预测模型 ············································································.31 3.1 大气运动的基本概念 ·········································································.31 3.1.1 大气运动的基本方程 ································································.31 3.1.2 大气中尺度环流 ······································································.31 3.1.3 莫宁-奥布霍夫相似理论 ····························································.32 3.2 蒸发波导预测模型——PJ 模型 ····························································.33 3.2.1 PJ 模型的基本理论 ···································································.33 3.2.2 计算机仿真结果 ······································································.35 3.3 蒸发波导预测模型——伪折射率模型 ···················································.37 3.3.1 伪折射率模型的基本理论 ··························································.37 3.3.2 计算机仿真结果 ······································································.40 3.4 蒸发波导预测模型——NPS 模型 ·························································.41 3.4.1 NPS 模型 ···············································································.42 3.4.2 NPS 模型在稳定条件下的改进 ····················································.44 3.5 蒸发波导高度对气象要素的敏感性分析 ················································.46 3.6 冷空气条件下不同蒸发波导预测模型的对比 ··········································.48 3.6.1 4 种蒸发波导预测模型的对比 ·····················································.49 3.6.2 冷空气条件下的电磁波传播实验 ·················································.56 本章小结 ·······························································································.63 本章参考文献 ·························································································.63 第4 章 蒸发波导高度时空分布规律 ································································.65 4.1 蒸发波导统计分析的方法与数据源 ······················································.65 4.2 世界海洋蒸发波导高度的时空分布规律及其成因分析 ······························.70 4.2.1 世界海洋蒸发波导高度的时空分布规律 ········································.70 4.2.2 世界海洋蒸发波导高度的时空分布规律的成因分析 ·························.74 4.3 西太平洋蒸发波导高度的时空分布规律及其成因分析 ······························.77 4.3.1 西太平洋蒸发波导高度的时空分布规律 ········································.77 4.3.2 西太平洋蒸发波导高度的时空分布规律的成因分析 ·························.82 4.4 中国南海蒸发波导高度的时空分布规律及其成因分析 ······························.87 4.4.1 中国南海蒸发波导高度的时空分布规律 ········································.88 4.4.2 中国南海蒸发波导高度的时空分布规律的成因分析 ·························.94 4.5 亚丁湾蒸发波导高度的时空分布规律及其成因分析 ·································.96 4.5.1 亚丁湾蒸发波导高度的时空分布规律 ···········································.97 4.5.2 亚丁湾蒸发波导高度的时空分布规律的成因分析 ···························.104 4.6 蒸发波导高度时空分布规律的实验验证 ···············································.106 4.6.1 海上实验概况 ········································································.106 4.6.2 海上实验结果 ········································································.107 本章小结 ······························································································.108 本章参考文献 ························································································.109 第5 章 蒸发波导环境特性实时监测及短期预报方法 ·········································.110 5.1 蒸发波导环境特性实时监测方法 ························································.110 5.1.1 蒸发波导环境特性实时监测方法概述 ··········································.110 5.1.2 船载气象观测系统的组成及其测量数据的可靠性分析 ·····················.111 5.1.3 蒸发波导预测模型对气象参数误差敏感性分析 ······························.116 5.1.4 传感器类型选择及其安装位置建议 ·············································.122 5.2 蒸发波导环境特性短期预报方法 ························································.123 5.2.1 基于GFS 数据的蒸发波导环境特性短期预报方法 ··························.123 5.2.2 基于WRF 模型的蒸发波导环境特性短期预报方法 ·························.126 本章小结 ······························································································.131 本章参考文献 ························································································.131 第6 章 蒸发波导与海水蒸发量的关系 ···························································.132 6.1 概述 ·····························································································.132 6.2 数据和方法 ····················································································.133 6.2.1 数据·····················································································.133 6.2.2 数据处理与分析方法 ·······························································.135 6.3 蒸发波导高度和蒸发量关系的定性分析 ···············································.135 6.3.1 蒸发波导高度和蒸发量时空演变的基本特征 ·································.135 6.3.2 蒸发波导高度和蒸发量经验正交函数分析结果 ······························.137 6.3.3 海面风速和海水表面温度的相对影响分析 ····································.140 6.4 通过蒸发量定量估算蒸发波导高度 ·····················································.144 6.4.1 气海环境因素的敏感性分析 ······················································.144 6.4.2 定量关系的统计分析 ·······························································.146 本章小结 ······························································································.150 本章参考文献 ························································································.150 第7 章 蒸发波导中的电磁波传播模型 ···························································.153 7.1 射线追踪模型 ·················································································.153 7.1.1 射线追踪模型简介 ··································································.153 7.1.2 射线及几何光学的基本原理 ······················································.153 7.1.3 射线追踪模型的推导 ·······························································.154 7.2 抛物方程模型 ·················································································.156 7.2.1 抛物方程简介 ········································································.156 7.2.2 抛物方程模型的推导 ·······························································.156 7.2.3 抛物方程的解法 ·····································································.159 7.2.4 边界条件、初始场及电磁波传播路径损失 ····································.165 7.3 混合模型 ·······················································································.168 本章小结 ······························································································.168 本章参考文献 ························································································.169 第8 章 海洋蒸发波导中的电磁波传播特性 ·····················································.170 8.1 水平均匀蒸发波导中的电磁波传播仿真结果 ·········································.170 8.1.1 射线追踪模型下水平均匀蒸发波导中的电磁波传播仿真结果 ············.170 8.1.2 抛物方程模型下水平均匀蒸发波导中的电磁波传播仿真结果 ············.170 8.2 水平不均匀蒸发波导对电磁波传播的影响 ············································.173 8.2.1 水平不均匀蒸发波导特性分析 ···················································.173 8.2.2 仿真计算 ··············································································.175 8.2.3 海上实验结果及分析 ·······························································.180 8.3 海上障碍物对蒸发波导中的电磁波传播的影响 ······································.184 8.3.1 障碍物模型 ···········································································.184 8.3.2 仿真计算 ··············································································.185 8.3.3 海上实验结果及分析 ·······························································.190 8.4 海面粗糙度对蒸发波导中的电磁波超视距传播的影响 ·····························.194 8.4.1 海面粗糙度的计算方法 ····························································.194 8.4.2 仿真计算结果及分析 ·······························································.195 8.5 海洋蒸发波导信道的多径效应分析及实验 ············································.197 8.5.1 模型的理论和方法 ··································································.198 8.5.2 仿真条件计算结果及分析 ·························································.198 8.5.3 实验数据及解释 ·····································································.201 8.6 蒸发波导信道的频率响应 ··································································.205 8.6.1 频率响应的计算方法 ·······························································.205 8.6.2 仿真计算 ··············································································.206 8.6.3 海上实验及结果分析 ·······························································.210 本章小结 ······························································································.214 本章参考文献 ························································································.215 第9 章 蒸发波导数据传输系统 ····································································.217 9.1 蒸发波导数据传输系统的辅助决策方法 ···············································.217 9.1.1 蒸发波导信道的路径损失 ·························································.218 9.1.2 通信系统能力的计算 ·······························································.219 9.1.3 辅助决策方法的确定 ·······························································.220 9.2 蒸发波导数据传输系统的参数优化 ·····················································.221 9.2.1 最优天线高度 ········································································.221 9.2.2 最优工作频率 ········································································.223 9.3 蒸发波导数据传输系统的可通概率 ·····················································.224 9.3.1 可通概率的计算方法 ·······························································.224 9.3.2 可通概率计算结果 ··································································.225 9.4 海上实验验证 ·················································································.229 9.4.1 实验概况 ··············································································.229 9.4.2 实验验证结果 ········································································.230 本章小结 ······························································································.231 第10 章 蒸发波导反演方法 ·········································································.232 10.1 蒸发波导反演的概况 ······································································.232 10.2 利用电磁波传播路径损失反演蒸发波导修正折射率剖面 ·························.234 10.2.1 利用基于地形抛物方程模型得到的路径损失反演蒸发波导修正折射率 剖面的方法 ··········································································.234 10.2.2 TPEM 模型对电磁波传播路径损失的数值模拟及反演仿真 ··············.235 10.3 利用雷达海杂波反演蒸发波导修正折射率剖面 ·····································.239 10.3.1 反演步骤及过程 ····································································.239 10.3.2 雷达海杂波相关模型和功率求解 ···············································.241 10.3.3 正向模型的数值模拟及反演仿真 ···············································.246 本章小结 ······························································································.248 本章参考文献 ························································································.249 第11 章 基于BP 神经网络算法的蒸发波导预测模型 ··········································.250 11.1 基于BP 神经网络算法的蒸发波导建模基本原理 ···································.250 11.1.1 BP 神经网络算法 ···································································.250 11.1.2 训练及验证数据 ····································································.253 11.1.3 训练次数对均方根误差的影响 ··················································.254 11.2 稳定与不稳定条件下的训练结果对蒸发波导预测模型的影响 ···················.259 11.2.1 不稳定条件下的训练结果及分析 ···············································.260 11.2.2 稳定条件下的训练结果及分析 ··················································.263 本章小结 ······························································································.267 本章参考文献 ························································································.267 第12 章 蒸发波导环境数据库软件 ·······························································.268 12.1 软件设计的总体思路 ······································································.268 12.2 海区网格选择功能模块 ···································································.268 12.3 海区网格蒸发波导特性功能模块 ·······················································.270 12.4 全球蒸发波导特性功能模块 ·····························································.272 12.5 西太平洋蒸发波导特性功能模块 ·······················································.274 12.6 蒸发波导剖面预测功能模块 ·····························································.275 本章小结 ······························································································.276