公开(公告)号：US06411566B1

公开(公告)日：2002-06-25

申请号：US09912655

申请日：2001-07-25

申请人： Richard A. Katz ,  Azizul H. Quazi

发明人： Richard A. Katz ,  Azizul H. Quazi

IPC分类号： H04B106

CPC分类号： H04B11/00 ,  G01S3/8006 ,  H04B13/02

摘要： A nonlinear signal processing system and method is used to identify nonlinearity (e.g., chaos) in underwater acoustic signals, such as sonar signals. The system and method detects the underwater acoustic signal and digitizes the underwater acoustic signal to produce an acoustic time series. The acoustic time series is reconstructed using a phase space embedding algorithm to generate a phase space embedded acoustic signal. A differential radius signal is generated from the phase space embedded acoustic signal using chaotic radius computations and differential radius computations. Thresholds can be detected in the differential radius signal to reveal nonlinear or chaotic events hidden in the underwater acoustic signal.

摘要翻译： 非线性信号处理系统和方法用于识别水声信号（例如声纳信号）中的非线性（例如混沌）。 该系统和方法检测水声信号，并对水声信号进行数字化，产生声学时间序列。 使用相空间嵌入算法重建声学时间序列，以产生相位空间嵌入声信号。 使用混沌半径计算和微分半径计算从相位空间嵌入声信号产生差分半径信号。 可以在差分半径信号中检测阈值，以揭示隐藏在水下声信号中的非线性或混沌事件。

公开(公告)号：US5668778A

公开(公告)日：1997-09-16

申请号：US677205

申请日：1996-07-09

申请人： Azizul H. Quazi

发明人： Azizul H. Quazi

IPC分类号： H04B11/00 ,  H04B1/06

CPC分类号： H04B11/00

摘要： A method for detecting radiated and reflected acoustic signals from an unwater source, wherein the acoustic signals are present in a random noise environment and form an output therewith. The method includes the steps of operating an entropy-based acoustic receiver to receive the output, calculating the entropy of the received output, and comparing the calculated entropy with a selected entropy threshold value. A substantial difference is indicative of the presence of an acoustic signal from an underwater source. A less than substantial difference is indicative of a lack of presence of an acoustic signal from an underwater source.

摘要翻译： 一种用于检测来自水下源的辐射和反射声信号的方法，其中所述声信号存在于随机噪声环境中并与其形成输出。 该方法包括以下步骤：操作基于熵的声接收器以接收输出，计算接收到的输出的熵，以及将所计算的熵与所选择的熵阈值进行比较。 实质上的差异表示来自水下源的声信号的存在。 不太明显的差异表明缺乏来自水下源的声信号的存在。

公开(公告)号：US5841735A

公开(公告)日：1998-11-24

申请号：US890479

申请日：1997-07-09

申请人： Azizul H. Quazi

发明人： Azizul H. Quazi

IPC分类号： H04B11/00 ,  G01S3/80

CPC分类号： H04B11/00

摘要： A method for processing acoustic signals received by first and second undater detectors, spaced from each other, for detection and determination of range and bearing of an underwater signal source, includes the steps of obtaining a time series xd of first random variables X from the first detector, obtaining a time series yd of second random variables Y from the second detector, and providing a window of a selected number of digital points of time series xd and yd. The method further includes determining distribution of p(x,y), p(x), and p(y), wherein p(x,y)=joint distribution, p(x)=distribution of x, and p(y)=distribution of y, and estimating mutual information I(X;Y) of the random variables X,Y whereby to obtain a measure of dependence between the random variables X and Y in the window, whereby to determine whether xd and yd come from a single source, and if xd and yd are determined to have come from the same source, computing time differential in receipt of the X and Y signals by the first and second spaced detectors to provide the range and bearing of the source from the first and second detectors. The invention further relates to a system for performing the steps of the above method.

摘要翻译： 一种用于处理由第一和第二水下检测器接收的声信号的方法，用于检测和确定水下信号源的范围和方位，包括以下步骤：从第一个第一随机变量X获得第一随机变量X的时间序列xd 从第二检测器获得第二随机变量Y的时间序列yd，并提供选定数量的时间序列xd和yd的数字点的窗口。 该方法还包括确定p（x，y），p（x）和p（y）的分布，其中p（x，y）=联合分布，p（x）= x的分布和p（y） = y的分布，并估计随机变量X，Y的互信息I（X; Y），从而获得窗口中的随机变量X和Y之间的依赖性的度量，从而确定xd和yd是否来自 单个源，并且如果xd和yd被确定为来自相同源，则计算由第一和第二间隔检测器接收X和Y信号的时间差，以提供来自第一和第二信号的源的范围和方位 探测器 本发明还涉及一种用于执行上述方法的步骤的系统。