中文摘要：

针对传统灰度模型光流法计算海面风场误差较大的问题，提出了改进海面风场反演算法，该算法包含2部分：一是根据航海雷达图像特点，提出了基于灰度和梯度不变模型光流法的海面风向反演算法，并应用直方图统计光流场计算主风向；二是应用BP网络建立风速与雷达散射截面、电磁波方向与风向的非线性模型，据此计算风速.最后应用模拟、实测图像开展实验，对风向和风速反演结果进行比对、分析.实验结果表明，航海雷达具有很高测量风速、风向的能力，同时也验证了文中算法的可行性.

英文摘要：

Considering the big error exits in traditional gray model optical flow method for calculating ocean surface wind, a novel method is proposed, which consists of two parts. Firstly, Ocean wind direction retrieval algorithm based on brightness and gradient constancy model according to the characteristic of sea clutter was proposed. Furthermore, main wind direction can be achieved by analyzing optical flow field. The other is wind speed retrieval algorithm. By applicatingBP neural network for constructing model among wind speed, radar cross section, radio direction and wind direction, wind speed can be derived. Finally, simulated and real radar images are used for experiments, and then we compare the measured wind vector with real wind vector. The results show that the X-band radar does a good job in measuring wind vector, and the wind vector reversion algorithm has a good feasibility.