基于船舶运动的微波多普勒海面回波模拟与分析

Simulation and Analysis of Microwave Doppler Sea Surface Echo Based on Ship Motion

根据船载雷达探测海面时的工作特点,深入研究走航状态下微波段电磁波与海表面的作用机理。根据线性波浪理论和船舶运动规律,建立了基于时变海面的船舶运动模型,并通过与实测数据对比验证了模型的有效性。采用小斜率近似法计算海面的电磁散射,仿真得到走航状态下微波段海面散射回波,并分析了不同船舶运动方式对回波多普勒谱的影响。通过采用空间海浪反演算法验证仿真结果,证明了回波模拟算法的正确性。结果表明船舶运动导致回波统计特征发生明显变化,该结论为船载平台下海面后向散射回波研究与海浪反演算法改进提供了先验信息与理论模型。

According to the working features of shipborne radar in detecting sea surface,the interaction mechanism between micro band electromagnetic wave and sea surface was studied deeply.According to the linear wave theory and the law of ship motion,a ship motion model based on time-varying sea level was established,and the validity of the model was verified by comparing with the measured data.The small slope approximation method was used to calculate the electromagnetic scattering of the sea surface,the microwave band sea surface scattering echo under the navigation state was obtained by simulation,and the influence of different ship motion modes on the echo Doppler spectrum was analyzed.The simulation results were verified by the spatial wave inversion algorithm,which proved the correctness of the echo simulation algorithm.The results show that the ship motion results in significant changes in the statistical characteristics of the echo,which provides a prior information and theoretical model for the study of the sea surface backscatter echo and the improvement of the wave inversion algorithm under the ship platform.