| 摘要: |
| 保持与陆地的联系对于船只在浩瀚的海洋中航行非常重要。来自陆地的高频信号经电离层和海面多次折反射后到达船只，受到不同海况的传播衰减特性影响。针对粗糙海面反射模型，从建立海面波动方程出发，考虑到波浪屏蔽对信号的影响，建立了新的反射衰减模型。利用该模型进行仿真，得到高频信号超视距海上传播的最大跳变规律。分析了湍流海面和平静海面对高频信号衰减的差异，揭示了海浪遮挡是引起差异的主要因素。对于航行在波涛汹涌的海面上的船舶，建立了包含浪和涌特征的多路径反射叠加模型，该模型考虑了大尺度波和小尺度波的海面情况，更加接近实际情况。最后利用所建立的模型计算了高频信号的最大跳数和通信距离。 |
| 关键词: 高频信号 恶劣海况 多跳传播 |
| DOI： |
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| 基金项目: |
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| Propagation Characteristic Analysis of Multi-hop HF Signals in Turbulent Sea State |
| ZHENG Changgang |
| (Glasgow College,University of Electronic Science and Technology of China,Chengdu 611731,China) |
| Abstract: |
| Keeping in touch with the land is very important for ships sailing across the vast ocean.Radio signals from ground are refracted off the ionosphere and reflected off the surface of the sea to reach the shipboard receiver.So,study on attenuation of reflect signals in different sea states is meaningful.For the reflect model of the rough sea,this paper builds a new direct reflection model with one hop,which considers the attenuation factor of blocked signal caused by wave shield.It conducts simulation with this model and obtains the regularities of maximum hops of high frequency(HF) signals transferred on the sea.For the signal attenuation difference of turbulent sea and calm sea to the rough land and smooth land,it compares the factors affecting the attenuation and finds the main difference is the reflection coefficient.For ships sailing on turbulent sea,the model of direct reflection of the sea with one hop needs to be changed,so a new model is built and applied to superposition of multiple-path reflection,which considers different circumstances of the sea including large-scale wave and small-scale wave.Finally,the maximum number of hops of HF signal and the maximum communication distance are calculated by using the model built. |
| Key words: HF signal turbulent sea state multi-hop propagation |
《电讯技术》编辑部 