ETF算法在SAS成像处理中的应用研究

在传统ETF（Exact transfer function）成像算法的基础上，根据SAS（synthetic aperture sonar）应用中较为普遍的发射器和接收器收发分置的基本模型，该文详细推导得到了一种应用于SAS成像的改进的最优ETF算法，分析并推导得到了算法使用中应该满足的分块处理条件。由于该改进算法推导过程中聚焦函数的方位相位的计算不作近似截取而是做准确计算，使得该算法具有最优的相位精度。同时，分块处理条件的推导，为数据的并行运算提供了依据。该算法对数据分块进行并行处理，使得算法运算速度得到提高，有利于算法应用的快速实现。最后，该文使用点目标回波仿真数据对算法的效果进行了验证，成像结果证明了该改进算法的有效性。

An Improved ETF Algorithm for SAS Imaging

According to conventional ETF(exact transfer function) algorithm,based on the fundamental model in the application of SAS(synthetic aperture sonar)with separated transmitter and receivers,optimum exact transfer function for SAS imaging is deduced in detail.Block processing requirement is analyzed and developed in detail for practical use and serves well for parallel computing.Because the evolution is based on precise computing instead of approximate truncation for azimuth phase preservation,the algorithm has optimum phase precision.Meanwhile blocks and parallel processing accelerate the processing.Results for processing simulated point targets show the validity of the algorithm.