方位向时变非均匀采样的合成孔径声纳成像

采用多接收阵技术能够使合成孔径声纳的测绘速率和测绘带同时得到提高,但带来了方位向非均匀采样以及不满足停走停假设的问题.本文建立了高测绘速率、宽测绘带条件下不做停走停近似的多接收阵合成孔径声纳信号模型,采用频域方法对合成孔径声纳时变的非均匀方位向信号进行了重构,并导出了重构方法的快速算法.重构方法解决了高测绘速率、宽测绘带条件下的偏移及散焦问题.仿真和实验验证了该方法的可行性.

Synthetic aperture sonar image reconstruction with Variational non-uniform sampling in azimuth

Synthetic aperture sonar (SAS) with multiple-receiver can improve the mapping rate and swath widen simultaneously, and suffer from some new problems, such as non-uniform sampling in azimuth and unfitting the approximation of stop-and-hop at the same time. In this paper, a novel multiple-receiver SAS signal model is proposed on the background of high mapping rate and wide swath, and then a method of variational non-uniform sampling reconstruction is presented without the approximation of stop-and-hop using the method of frequency domain. A fast algorithm of reconstruction is also proposed, which has the same computation complex level with FFT. The proposed method can avoid the excursion and defocusing in the SAS imaging process with high mapping rate and wide swath. The simulation and trial results show the validity of this method.