摘要
传统的距离-多普勒算法主要应用于合成孔径成像中正侧视或小斜视角情况。在合成孔径声呐实际应用中,经常需要在较大的斜视角模式下对目标成像,而此时距离向和方位向的耦合会非常严重。在研究经典距离-多普勒算法原理的基础上,改进了适合大斜视角条件下成像的距离-多普勒算法。在放弃菲涅尔近似的条件下,提出了更精确的距离双曲线模型,并对算法进行了重新推导。提出了新的二次距离压缩方法,能更好地消除距离向和方位向的耦合。利用改进算法对成像区域中任意多个点目标上进了成像仿真。仿真结果表明,改进算法具有较高的分辨率和适中的运算量,比传统算法更适合应用于大斜视角成像。
The traditional Range-Doppler algorithm is mainly used in side looking or small squint angle mode of synthetic aperture imaging. In application of synthetic sonar,the large squint angle imaging is often required and the range-azimuth coupling is serious. On the basis of studying the principle of the classical range Doppler algorithm,it improved the imaging algorithm in large squint mode. A more accurate range hyperbolic model is proposed and then the algorithm is deduced under the condition of abandoning the Fresnel assumption. The new secondary range compression method proposed in the paper is expected to eliminate effectively the range-azimuth coupling.Any point target is simulated in imaging region by using the improved algorithm. The simulation conclusion showed that the improved Range-Doppler algorithm had higher resolution and moderate computational complexity as compared with the traditional algorithm
出处
《西北工业大学学报》
EI
CAS
CSCD
北大核心
2016年第2期201-207,共7页
Journal of Northwestern Polytechnical University
基金
国家自然科学基金(51209173)资助
关键词
合成孔径声呐
距离-方位耦合
二次距离压缩
泰勒级数
菲涅尔假设
synthetic aperture sonar
range-azimuth coupling
secondary range compression
taylor series
fresnel assumption
