蒸发波导环境中微波传播敏感性分析  

Sensitivity Analysis of Microwave Propagation in the Evaporation Duct

作　　者：张琪 殷富宇 ZHANG Qi;YIN Fuyu(School of Marine Sciences,Nanjing University of Information Science and Technology,Nanjing 210044,China)

机构地区：[1]南京信息工程大学海洋科学学院,江苏南京210044

出　　处：《海洋技术学报》2023年第1期40-52,共13页Journal of Ocean Technology

基　　金：国家自然科学基金资助项目(41906167);电波环境特性及模化技术重点实验室基金资助项目(6142403190101)。

摘　　要：海洋蒸发波导是微波通信的优良天然信道,但微波信号在波导中传播时容易受气海环境因素变化的影响。本文采用扩展傅里叶幅度敏感性分析法(Extended Fourier Amplitude Sensitivity Test,EFAST),分析了蒸发波导环境中微波传播路径损失对空气温度、海表温度、近海面风和相对湿度等气海环境因素变化的敏感性特点。敏感性分析结果呈现一种频率相关的频散特性,而信号极化方式影响较小。这4种环境因素中,相对湿度对路径损失的整体影响最大;在传播距离较近且高度较高的范围内近海面风速对传播的影响占据主导;空气温度和海表温度的敏感性大致相当;风速的影响是4种环境因素中最为复杂的,这也是在实际分析中需要额外重视的。本文对蒸发波导环境参数的敏感性分析结果对现场波导观测试验具有重要的参考意义,对敏感度高的环境参数可以考虑优先进行高时空分辨率观测。此外,在运用中尺度数值天气预报模式进行蒸发波导预报时,优先发展与敏感度高的气海参数有关的物理过程参数化方案,可以节约计算时间和资源。Oceanic evaporation duct is an excellent natural channel for microwave communication,but microwave signals are easily affected by the air-sea environmental factors when propagating in the duct.In this paper,the Extended Fourier Amplitude Sensitivity Test is applied to examine the sensitivity of the microwave propagation path loss to environmental parameters including air temperature,sea surface temperature,near-surface wind,and relative humidity.The results show a frequency-dependent dispersion characteristic,while the signal polarization has little effect.Among the four environmental factors.relative humidity has the greatest impact on the path loss.Within the area of short distance and high altitude,the wind speed dominates the propagation.The sensitivities of air temperature and sea surface temperature is roughly equivalent.The influence of wind speed is rather complicated and requires extra attention in the analysis.The sensitivity analysis results in this paper have important reference significance for the evaporation duct observation experiment.For the environmental parameters with high sensitivity,high spatial-temporal resolution observations can be given priority.In addition,when using mesoscale numerical weather prediction models for evaporation duct forecasting,priority is given to the development of parameterization schemes for physical processes related to air-sea parameters with high sensitivity,which can save computing time and resources.

关 键 词：蒸发波导 微波传播 路径损失 扩展傅里叶敏感性分析法 

分 类 号：TN925[电子电信—通信与信息系统]