利用合成孔径技术提取表层海流的新算法

为满足高频地波雷达单站提取表层海流的需求，提出了一种利用合成孔径技术提取表层海流的新算法，并通过仿真验证其可行性。首先描述系统组成、实现方式和信号模型，然后基于线性调频信号参数的迭代估计方法提出了流速估计算法，最后实现了在一个海域分辨单元上提取表层海流的仿真试验。结果表明，通过选取适当的方位分辨单元大小，并从方位向回波中提取信号参数，该算法能够估计出表层海流的流速和流向，且精度满足要求。这表明利用高频地波合成孔径雷达实现单站提取表层海流在理论上是可行的。

A Novel Algorithm on Extracting Sea Surface Current by Synthetic Aperture Technique

To meet the requirement of extracting surface current by a single station of HF surface wave radar, we present a novel algorithm by synthetic aperture technique in this paper. Also we verify the feasibility of this algorithm by simulation. Firstly the composition, implementation and signal model are described. Then the velocity estimation algorithm is introduced based on an iterative approach to estimate the parameters of chirp signals. Finally, numerical experiment of extracting surface current is implemented for a single resolution cell. The results show that if the size of a resolution cell in azimuth direction is properly chosen, the velocity of surface current can be estimated by extracting signal parameters from the azimuth echo. The precision is enough to meet the requirements. It indicates that high frequency SAR is theoretically feasible to be used in surface current extraction by a single station.