风浪因素对海洋波导雷达回波作用机理的研究

采用文氏谱模型描述近海海洋动力环境海面的粗糙特征, 并运用海浪谱理论得到风速和均方根高度偏差的关系. 进而应用修正的离散混合傅里叶变换方法和改进的雷达散射系数模型分别计算了电磁波传输损耗和雷达散射系数. 在此基础上, 通过数值计算分析了风浪因素对海洋波导环境雷达回波功率值的影响. 结果表明, 风浪因素对不同观测高度处的传输损耗的影响均不大; 风浪因素对雷达回波功率有显著影响, 并且相对于传输损耗, 雷达散射系数项受风浪因素影响较大因而导致较大的雷达回波功率的变化.

Study on effect of wind waves on radar echoes in atmosphere duct oversea

The Wen's wave spectrum model is adopted to describe the rough sea surface, and the relation between wind and ocean waves using sea wave spectrum theory is derived. The improved discrete mixed Fourier transform algorithm and the modified rader scattering coefficient model are used to calculate radio propagation loss and radar cross section respectively. On this basis, the influence of wind waves on radar echoes in the environment of atmosphere ducts is analysed by using numerical calculations. The results show that the influences of wind on propagation loss at different heights are different; wich respect to the propagation loss, rader scattering coefficient influenced by waves of factors is large, which results in large change in the radar echo power.