近场宽带LFM信号被动测向和测距方法  

Passive DOA and range estimation method for near-field broadband LFM signals

作　　者：李军[1,2] 林秋华[1] 杨秀庭[2] 康春玉[2] 

机构地区：[1]大连理工大学电子信息与电气工程学部,辽宁大连116024 [2]海军大连舰艇学院信息作战系,辽宁大连116018

出　　处：《系统工程与电子技术》2016年第8期1737-1743,共7页Systems Engineering and Electronics

基　　金：国家自然科学基金(61271443;61471378)资助课题

摘　　要：提出了一种采用分数阶傅里叶变换的聚焦波束形成被动定位方法,实现了水声近场宽带线性调频(linear frequency modulated,LFM)信号的被动测向和测距。建立了基于球面波模型的近场宽带LFM信号接收数据模型,应用分数阶傅里叶变换(fractional Fourier transform,FRFT)将LFM信号的时变阵列流形矩阵变换为固定阵列流形矩阵,结合近场声源的聚集波束形成技术,利用多重信号分类算法实现了对多个宽带LFM信号的方位与距离联合估计。数值仿真验证了该方法对水声目标方位和距离估计的有效性,并仿真分析信噪比、声源距离、声源个数等对该算法性能的影响。A passive underwater acoustic localization method using fractional Fourier transform（FRFT）and focused beamformer is proposed.The direction-of-arrival and range information of the near-field broadband linear frequency modulated（LFM）signals can be estimated.The near-field spherical wave model for broadband LFM signal is introduced and the time-varying array manifold matrix corresponding to the LFM signals is changed into a fixed array manifold matrix by using FRFT.Combined with the near-field focused beamforming technology and multiple signal characteristics algorithm,the azimuths and distances of multiple broadband LFM signals will be estimated.The validity and efficiency of the proposed method is verified by simulations and experiments,and the performance of the proposed method is discussed in terms of signal-to-noise ratio,azimuth and distance of the underwater acoustic signal.

关 键 词：线性调频信号 被动测距 分数阶傅里叶变换 多重信号分类法 

分 类 号：TN911.5[电子电信—通信与信息系统]