由于海上信号传输受海水蒸发、潮汐运动等独特海洋环境影响，现有地面通信信道模型不适用于海域通信，而现有海上信道模型仍未充分考虑上述环境因素。为研究海洋环境对无线传输的影响，在中国黄海海域进行了信道测量，并实时采集船舶所在海域的水文和气象信息。在测量基础上，针对海水蒸发，根据海况参数和接收信号的功率时延谱等判断实验环境下海上蒸发波导的存在性；针对潮汐运动，提出潮汐因子修正的两径时变信道模型，并验证信道小尺度衰落符合Rice分布。实测数据与理论模型的拟合结果表明，所提出的信道模型比现有模型可以更好地刻画时变海况环境下黄海海域的信道特性。
Since signal transmissions over the sea surface are affected by the marine environment including seawater evaporation and tidal motion, existing terrestrial channel models are not suitable for maritime communications since they do not consider the effects of these environmental factors. This study evaluates the effect of the marine environment on wireless transmissions using channel measurement experiments in the Yellow Sea. The real-time hydrological and meteorological information in the area was also collected. The effect of seawater evaporation was modeled by an evaporation duct along the surface based on the sea state parameters with an analysis of the sensitivity of the duct height to various parameters. The effect of the tidal motion was modeled using a modified two-ray channel model that includes a tidal factor with the model verifying that the small-scale channel fading follows the Rice distribution. Comparison of the models with the measured data shows that this channel model better describes the channel characteristics over the Yellow Sea with a time-varying sea state environment than existing models.
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