A study of VHF radio wave propagation over a water surface of variable conductivity
A study of VHF radio wave propagation over a water surface of variable conductivity
复制标题
甚高频无线电波在可变电导率水面传播的研究
DOI：
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发表时间：
1991
期刊：
影响因子：
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通讯作者：
P. Broche
中科院分区：
文献类型：
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作者：
P. Forget;P. Broche
本文从理论和实验两方面研究了甚高频无线电波在不同粗糙度和不同电导率的非均匀海面上的传播。理论模拟预测地面波衰减因子的高灵敏度后，表面电导率的大的变化，可以发现在河口。这种灵敏度可能受到在取风限制条件下的大风和在充分发展的海洋的更广泛的风速范围下的海况的明显影响。本文报告了在河流羽流上方进行的VHF雷达实验的结果，并提供了适当的现场文件。验证了电导率分布对无线电波传播影响的理论预期。由于遇到的低风速，风/波的影响是明显的，只有在提取限制条件下的雷达截面系数（线性相关的布拉格波频谱能量）的变化。此外，这些变化在某些情况下可以归因于河流羽流中浮油的影响。研究表明，VHF雷达技术可用于遥感海面电导率。
The ground wave propagation of VHF radio waves over an inhomogeneous sea surface of variable conductivity and under various sea roughness conditions is studied both theoretically and experimentally. Theoretical simulations predict a high sensitivity of the ground wave attenuation factor upon large variations of the surface conductivity, as can be found in an estuary. This sensitivity can be influenced appreciably by the sea state under high winds in fetch-limited conditions and under a broader range of wind speeds for a fully developed sea. Results from a VHF radar experiment over a river plume with appropriate in situ documentation are reported here. They validate the theoretical expectations on the influence of the conductivity profile on radio wave propagation. Because of the low winds encountered, the wind/wave influence is evident only on the variations of the radar cross-section coefficient (linearly related to Bragg wave spectral energy) in fetch-limited conditions. Also, these variations can be attributed in some cases to the influence of slicks in the river plume. The study suggests that the VHF radar technique may be used for remote sensing of sea surface conductivity.