宽测绘带的合成孔径声呐宽带Chirp Scaling成像算法  

A wideband Chirp Scaling imaging algorithm of synthetic aperture sonar based on wide swath

作　　者：杨海亮[1] 唐劲松[2] 徐慨[1] 

机构地区：[1]海军工程大学电子工程学院通信工程系,湖北武汉430033 [2]海军工程大学电子工程学院水声技术研究室,湖北武汉430033

出　　处：《哈尔滨工程大学学报》2015年第1期73-77,共5页Journal of Harbin Engineering University

基　　金：国家863计划基金资助项目(2007AA091101)

摘　　要：合成孔径声呐要实现高分辨率成像不可避免地需采用宽带发射信号,但目前大部分快速算法都是建立在窄带近似基础上的,采用宽带信号作为发射信号使得现有大量的成像算法不再适用。针对此问题,本文提出了一种改进的基于宽测绘带条件下的宽带非线性Chirp Scaling算法,它通过引入三次和四次预滤波使得频域二维传递函数的三阶耦合项随距离时变,并同时引入四次Chirp scaling因子控制新的距离向调频率随距离二次变化。仿真表明,改进的算法可在保证较高测绘带宽度的前提下提高合成孔径声呐的成像分辨率。To achieve high-resolution,the synthetic aperture sonar imaging requires wideband transmit signal,but most of algorithms are based on the narrow-band approximation and cannot be used. An improved wideband nonlinear Chirp Scaling algorithm for wide swath is proposed in this paper. In this algorithm,third order coupling term of the frequency-domain two-dimensional transfer function is change with the range by the cube and biquadratic prefiltering,and the range frequency modulation slope is change with the range because of the biquadratic chirp scaling factor. Simulation results show that the proposed algorithm can improves the imaging resolution with wide swath.

关 键 词：合成孔径声呐 宽测绘带 宽带 非线性 CHIRP Scaling成像算法 

分 类 号：TN957.52[电子电信—信号与信息处理]