四阶模型的多接收阵合成孔径声呐距离-多普勒成像算法

摘要

The sub-system composed of an element of the receiver array and the transmitter in Synthetic Aperture Sonar (SAS) is studied. Due to the double square rooted terms in the slant range history of the sub-system, the fourth-order Taylor expansion is used to approximate the slant range. Then, the system transfer function in two-dimensional frequency domain is derived via series reversion and the method of stationary phase. Based on that, a new Range-Doppler (R-D) imaging algorithm applied to long receiver array and wide beam cases is proposed. With the presented method, the echo signals corresponding to each sub-system are processed firstly. Next, a high resolution SAS complex image can be obtained by coherently superposing each individual image. The simulation and real datasets demonstrate the validity of the proposed method.%该文以多接收阵合成孔径声呐(Synthetic Aperture Sonar, SAS)中任意一个接收阵元和发射阵组成的子系统为研究对象，采用四阶泰勒多项式近似其具有双根号形式的斜距历程，利用级数反演方法和相位驻留原理推导了子系统的2维频域系统传递函数，并在此基础上提出一种适用于宽波束和长接收基阵情况下的距离-多普勒成像算法。该方法先对各子系统的回波数据进行成像处理，然后对所有的子图像进行相干叠加以获得所需的高分辨 SAS复图像。通过仿真实验和实测数据的验证，证明了该方法的有效性。