舰船辐射噪声超混沌现象研究  

Hyperchaos in behavior of ship radiated noise

作　　者：潘秀琴[1] 张春华[1] 黄海宁[1] 张洪[2] 

机构地区：[1]中国科学院声学研究所,北京100080 [2]成都电子科技大学电子工程学院,成都610045

出　　处：《应用声学》2005年第4期227-232,共6页Journal of Applied Acoustics

基　　金：国防预研基金资助项目

摘　　要：水下弱目标探测和识别一直是水声信号处理领域中研究的难点。从Lyapunov指数谱、吸引子相空间轨迹的演化、分形维数等方面,对船舶辐射噪声是否存在超混沌现象进行了研究。实验结果表明,船舶辐射噪声信号确实存在至少两个正的Lyapunov指数,即存在超混沌现象。辐射噪声吸引子在相空间中的轨迹具有多方向伸展的趋势,且不同类型目标的吸引子具有不同的分形维数。研究结果为建立精确描述辐射噪声信号的非线性模型、为水下弱目标信号探测和识别提供一定的理论依据。Detection and recognition of weak signal are difficult problems in underwater acoustics processing. To determine whether hyperchaotic behavior exists in the ship noise, by estimating the Lyapunov exponent spectrum, analyzing the phase space portrait, and computing the fractal dimension, is focused in this paper. Our results illustrate that two Lyapunov exponents actually exist in the Lyapunov exponent spectrum of the noise, and thus the noise could be characterized by hyperchaos. At the same time, it is shown that the noise attractor exhibit trend of stretching specialty at multi-direction is haven by, and also the noise from different type of object possesses different fractal dimension indicates. The results given in this paper, could provide novel theoretical foundation for the nonlinear character description of the ship noise, as well as for the latter detection and recognition.

关 键 词：混沌现象 舰船辐射噪声 LYAPUNOV指数谱 辐射噪声信号 水声信号处理 船舶辐射噪声 分形维数 非线性模型 吸引子 目标探测 空间轨迹 研究结果 信号探测 多方向 相空间 弱目标 识别 水下 

分 类 号：O415.5[理学—理论物理] U666.7[理学—物理]