无源声呐稀疏阵无栅瓣性能分析  

Beam pattern of sparse array for passive sonar

作　　者：吴国清[1] 王美刚[2] 

机构地区：[1]中国科学院声学研究所,北京100080 [2]山西大学工程学院信息系,太原030013

出　　处：《声学学报》2006年第6期506-510,共5页Acta Acustica

基　　金：大连水下测控技术国家重点实验室基金资助项目

摘　　要：计算机模拟、实际声呐信号和理论分析证明了在无源声呐中只要信号带宽足够宽(带宽大于1个倍频程),无源声呐中用稀疏阵,即基元间距大于信号波长的基阵,波束图中不会出现栅瓣特性。白化目标信号可满足尽量宽的信号带宽,有利于无栅瓣波束的设计。结论是只要保证足够宽的信号带宽,无源声呐工作频段中最高频率的波长可小于基阵中阵元间隔而可使阵波束特性不出现栅瓣。This work aims at sparse array without grating lobe for passive sonar, in order to increase frequency of the passive sonar and reduce the cost. According to traditional method, the distance between two contiguous sensors in sonar array should be less than the wavelength of highest frequency of the signal, otherwise the grating lobe appears on directivity pattern. The paper realizes that the conclusion of the grating lobe emergence it is not fit to the passive sonar due to the sine wave signal model in traditional method, in fact the input of passive sonar is random signal. The model of Gauss random process is fit to passive sonar which is used in this paper. From three aspect of the computer simulation, theory analysis and real passive sonar signal, it is revealed that the grating lobe do not appear on beam pattern when the distance between two contiguous sensors in passive sonar array is longer than wavelength of highest frequency if the signal band is wider than 1 oct. Whitening of the radiated noise can widen the frequency band, to ensure the beam pattern without the grating lobe. The conclusion is that the wavelength of signal can be shorter than the distance between two contiguous sensors without grating lobe if the band of radiated noise is wide enough.

关 键 词：无源声呐 稀疏阵 栅瓣 性能分析 信号带宽 波束特性 计算机模拟 目标信号 

分 类 号：TB56[交通运输工程—水声工程]