辐射噪声

基于EM算法的水下目标辐射噪声模型参数估计

EM-based Underwater Target Radiated Noise Model Parameters Estimation

舰船辐射噪声的分段自仿射IFS模型

Self-affine iterated function system model of ship radiated noise

基于MATLAB的舰船辐射噪声信号小波消噪处理

Eliminating noise processing of ship-radiated noise signal based on MATLAB

由于舰船辐射噪声具有正的最大Lyapunov指数及正的h2熵，说明舰船辐射噪声中确实有混沌成分存在。

There are positive maximum Lyapunov exponents and h_2 entropy , this indicated that ship radiated noise signals are chaotic .

舰船辐射噪声的小波域HMM分析

Analyzing the ship-radiated-noise with the wavelet-domain HMM model

对EDFA增益和自发辐射噪声的研究

Study on the gain and ASEN of EDFA

通过对仿真出来的信号进行功率谱分析与DEMON谱分析，该仿真能较好地体现舰船辐射噪声的基本声学特征。

The Simula lion can reflect typical acoustic characteristics of ship-radiated noise by processing and analyzing the simulated signal .

基于LOFAR谱和DEMON谱特征的舰船辐射噪声研究

Ship radiated-noise research based on the LOFAR spectrum and DEMON spectrum characteristics

为了检测舰船辐射噪声中的非线性特征，本文采用混沌、分形理论从信号产生的机理、相空间轨迹、分形维数和Lyapunov指数等4个方面着重研究了舰船辐射噪声的混沌现象。

Applying the theory of chaos and fractal to ship radiated noise , this paper analyzes signal generation and phase space portraits , calculates correlation dimension and estimates Lyapunov exponent .

基于考虑自发辐射噪声（ASE）的Giles模型，建立了EDFA的全光增益箝制理论模型。

Based on Giles model with amplified spontaneous emission ( ASE ), numerical simulation for the all - optical gain-clamped EDFA was carried out .

其结果表明，相对于传统DEMON分析，利用小波以及希尔伯特变换可以更快更好地提取舰船辐射噪声的调制信息。

Compared with traditional DEMON analysis , the result shows that modulated information of radiated noise of naval ships can be extracted more quickly through wavelet and Hilbert transform .

基于这些优化的线谱特征采用BP神经网络对海上实录的三类水下目标辐射噪声进行了分类识别，实验结果证明了方法的可行性和有效性，识别率达到90%以上，分类效果很好。

The classification experiment for three different classes of targets is done by BP network based on the optimized line-spectra , and the results of the experiment show that the spectrum-feature is effective and the classification rate is higher than 90 % .

基于声传递向量（ATV）的概念，研究探讨了ATV技术在内燃机结构辐射噪声仿真预测上的应用方法和途径。

Based on the acoustic transfer vector concept ( ATV ), the application approach to structural acoustic radiated prediction using the ATV technology for I. C.

建立了某微车有限元模型和边界元模型，分别用FEM、BEM和ATV方法预测了车内低频结构辐射噪声。

The finite element model and boundary element model were established , and the FEM , BEM and acoustic transfer vector ( ATV ) methods were respectively used to predict the low-frequency radiated noise .

用鱼雷辐射噪声数据进行了仿真研究，结果表明：该算法的性能优于基于LMS的自适应线谱增强器和基于短时相关的自适应线谱增强器。

Simulation with the torpedo-radiated data indicates that the proposed algorithms are much better than the ALE and the short-time correlation based adaptive line enhancer ( SCBALE ) in suppressing Gaussian noise and enhancing spectrum feature .

构建了基于外光反馈的混沌光通信系统模型，通过引入Langevin噪声源，建立了包含自发辐射噪声特性的主从式速率方程。

A chaotic optical communication system based on external optical feedback is constructed . By introducing the Langevin noise sources , the master-slave rate equations including spontaneous emission noise characteristics are deduced .

结果表明，在加入滑频滤波作用后，主要由放大器自发辐射噪声（ASE）所导致的孤子相位抖动，从无任何控制措施时的随距离立方增长变为随距离线性地变化；

The results show that the soliton phase jitter induced by spontaneous emission noise of amplifier increases only linearly as the propagation distance cube in the absence of control when the sliding-frequency guiding filters are used ;

针对水下目标识别的具体应用，构造了目标识别的D-S融合模型，对舰船辐射噪声的产生机理以及特征提取的基本方法作了详细阐述。

A D-S fusion model of target recognition is founded for the detailed application of underwater target recognition . The forming mechanism of the radiated noises of ships , submarines and torpedoes and the basic techniques of feature extraction are discussed .

采用基于负熵极大地快速独立分量分析（FastICA）算法，对该内燃机表面辐射噪声信号进行分离，得到一系列独立分量。

The negative entropy enormously fast independent component analysis ( FastICA ) algorithm was adopted to separate noise signals , and a series of independent components were obtained . 3 .

水声目标辐射噪声的包络谱中包含调制线谱（DEMON），不同类型的水声目标其DEMON谱不同，研究单矢量传感器利用DEMON谱检测目标信号的能力。

The spectral envelope of noise radiated from underwater acoustic targets consists of modulation line components ( DEMON ) . Based on the fact that different types of acoustic targets have different DEMON spectra , detection ability of single vector sensor with a DEMON spectrum is studied .

通过对实验和计算结果的对比分析，证明隔声去耦材料在200Hz以上能明显减小结构振动和降低辐射噪声。

After the experiment results and the calculation result analyzed and compared , it shows that the isolated sound and decoupled material can reduce the structural vibration and radiated noise clearly above 200 Hz .

在重构的相空间中分析了舰船辐射噪声的非线性特性，利用相似序列重复度这一参数，绘制了舰船辐射噪声RPT曲线并分析了其非线性特性；

In this paper , how to determinate those parameters of the time delay methed have been studied . In the phase space , by using of the similar sequence repeatability ( RPT ) and plotting the RPT curves it proved the nonlinear characteristics of the underwater noise .

而将正时机构由正时齿轮传动改为同步齿形带传动，可以大大改善前端测点的500Hz以上中、高频辐射噪声。

Changing the drive of timing mechanism from timing gear to notched belt can greatly reduce the high and medium frequency ( higher than 500 Hz ) radiated noise at front measuring point of the engine .

最后通过实验和分析得出，在相同光纤长度并考虑自发辐射噪声的前提下，与传统IFOG相比该新型RE-FOG的灵敏度可以提高2个数量级。

Lastly , a conclusion is drawn that the sensitivity can be improved at least by two orders of magnitude as compared to a conventional interferometric fiber optic gyroscope ( IFOG ) while having the same length of the fiber-optic coil and taking ASE noise into account .

舰船水下辐射噪声非线性特性研究

Study on the non - linearity of the underwater radiated noise

舰船辐射噪声源纵向分布的研究

Study on Longitudinal Distribution of Ship ′ s Radiated Noise Sources

水下航行器辐射噪声谱增强新方法

A New Method for Enhancing Noise Spectrum Radiated by Underwater Vehicle

舰船辐射噪声功率谱特征提取方法研究

A New Power Spectrum Feature Extractive Method of Ship Radiated Noise

一种水下目标辐射噪声调制特征提取方法

A Method for Modulation Feature Extraction of Underwater Target Radiated Noise

掺铒先纤放大器放大的自发辐射噪声的研究

Study of Amplified Spontaneous Emission in Erbium - doped fiber Amplifier