改进的多子阵双站合成孔径声纳成像算法

Improved imaging algorithm of multi-aperture bistatic aperture synthetic sonar

在常规单站SAS系统中,多子阵技术是提高测绘率的一个有效方法,针对发射站固定的双站SAS模型,多子阵技术同样可以用来解决测绘率与降空间采样率的矛盾,但是当"停-走-停"假设不再成立时,将引入相位误差项,降低双站SAS的成像质量,针对该问题在原有多子阵逐点成像算法的基础上,研究了发射站固定的双站SAS基阵运动引起的相位误差,提出了多子阵双站合成孔径声纳带相位补偿的逐点成像算法,在建立多子阵双站SAS数学模型的同时,形成了新的多子阵双站SAS系统方案设计。并给出了改进的波束形成逐点算法和仿真实验。改进的逐点算法并未改进运算量大小,新方法能够改善成像效果,仿真实验验证了该方法的有效性。多子阵双站合成孔径声纳成像的逐线算法有待进一步研究。

The multi-aperture is an effective technique for increasing coverage rate of imaging in monostatic synthetic aperture sonar （SAS）. In a special bistatic SAS （BiSAS） configuration with a fixed transmitter, the multi-aperture technique can also be used to deal with conflict between low space sampling rate and coverage rate of BiSAS. When the assumption of ＂stop-go-stop＂ is not effective, it will result in phase error that degrades the imaging quality. Based on the common dot-by-dot imaging algorithm, we discuss aperture movement during the signal transmitting time in a multi-aperture BiSAS system with fixed transmitter, and propose an improved dot-by-dot imaging algorithm with phase compensation. We also present and a new system design of multi-aperture BiSAS. Computer simulation results are given to show advantages of the improved algorithm and validity of the design.