Multi-frequency identification method in signal processing

Virtually vibration signals are always composed of many frequency components. Using the least squares method, a new multi-frequency identification algorithm has been proposed to identify the amplitude and phase of each component of a multi-frequency signal, and it will work well as long as the main frequency values are known. Based on this algorithm, two similar optimization procedures have been presented to obtain accurate frequency values for a sine-wave signal and a bi-tone signal, respectively. Assisted with band-pass filters and these optimization procedures, the multi-frequency identification algorithm can successfully identify the multi-frequency components of a signal. The multi-frequency identification method can be used to identify oil-film coefficients of journal bearing. And some reliable oil-film coefficients have been reached.     

Tektronix混合信号存储示波器在信号处理中的应用研究

介绍矩形窗函数的实验及TektrolqiXMS02000型混合信号永波器为数据处理和分析提供了大量真实的原始实验数据,及与仿真软件结合进行信号处理,克服信号采集和数字化硬件的瓶颈制约。     

ATmega128单片机在信号处理中的应用

以ATmega128单片机在钢水液位监控系统的信号处理子系统为例,详细介绍了系统对模拟量、数字量以及开关量的采集与处理过程,用LCD显示模块显示数据和状态的方法说明了一些为节省单片机引脚资源而采取的设计技巧,通过软件与硬件的结合,使信号的处理效果达到设计要求。     

Detection thresholds for tracking in clutter--A connection between estimation and signal processing

In the Kalman-Bucy filter and other trackers, the dependence of tracking performance upon the quality of the measurement data is well understood in terms of the measurement noise covariance matrix, which specifies the uncertainty in the values of the measurement inputs. The measurement noise and process noise covariances determine, via the Riccati equation, the state estimation error covariance. When the origin of the measurements is also uncertain, one has the widely studied problem of data association (or data correlation), and tracking performance depends critically on signal processing parameters, primarily the probabilities of detection and false alarm. In this paper we derive a modified Riccati equation that quantifies (approximately) the dependence of the state error covariance on these parameters. We also show how to use a receiver operating characteristic (ROC) curve in conjunction with the above relationship to determine the detection threshold in the signal processing system that provides measurements to the tracker so as to minimize tracking errors. The approach presented in this paper provides a feedback mechanism from the information processing (tracking) subsystem to the signal processing subsystem so as to optimize the overall performance in clutter.     

语音信号处理技术及其应用前景分析

语音识别技术目前的技术框架主要基于模式识别,对数据的匹配性要求很高,对方言、口音以及口语的处理能力还存在很大的瓶颈,即使是标准口音,也需要用户较高的配合度。、本文介绍了语音信号处理技术的研究现状及几种常见的技术方法,并且分析探讨了语音信号处理技术的应用和发展前景。     

LabVIEW和MATLAB在水声信号处理中的应用

本文结合LabVIEW虚拟仪器开发平台和MATLAB软件强大的数值分析功能的优点，利用LabVIEW和MATLAB混合编程技术应用于水声信号处理，该方法既能提供良好的计算机用户图形界面，又具有很强的水声信号处理能力，仿真结果表明了该方法的有效性。     

频域格兰杰因果关系及其在信号处理中的应用

自从格兰杰1969年提出因果关系的概念之后,格兰杰因果关系在信号处理、计算神经科学等许多领域的应用越来越广。人们可以利用格兰杰因果关系来分析多个变量之间的直接的相互作用,从而进一步研究各类变量之间的内在联系。以往都是在时域空间进行分析的,也就是说分析的对象都是时间序列数据,研究这些变量之间随着时间的变化是如何联系的。在时域空间的基础上,进一步从频域空间上对变量进行研究,分析在哪个频率段上变量之间存在相互作用,所得到的结论当然更具有意义。     

一种高增益GNSS-R码相位差测高信号处理方法

提出了一种GNSS-R码相位测高信号处理方法,可有效消除导航数据位对积分过程的影响,降低动态条件下多普勒的影响以及积分过程中平方损失的影响,提高处理增益。通过机载和岸基试验对该方法进行验证,机载试验结果显示,在相同的积分条件下,测高精度比传统的非相干积分方法提高约15%;岸基试验结果显示,该方法可有效延长积分时间,实现约0.43 m的测高精度。     

一种快速离散小波变换算法及其在语音信号中的应用

随着小波分析的理论研究水平不断提高,其应用领域也在不断扩展。特别是其多分辨率分析和Mallat算法在数字信号处理和数字通信中得到了广泛的应用。但是如果直接按照上述算法计算信号的小波分解和重构,其计算量将是很大的。通过对实序列的快速傅里叶变换(FFT)算法的推导及Mallat算法原理的分析,根据离散小波变换算法结构特征,提出了一种基于FFT的快速离散小波变换算法,并从数学理论上进行了论证。同时把该算法应用到实际的语音信号处理中,得到了很好的快速分解和重构效果。     

量子信号处理

对量子系统的基本原理以及建立在对这一理论体系进行仿真基础上的量子信号处理算法的理论框架进行了分析和研究,提出了量子信号处理在信号处理和图像处理领域的应用方法,并根据量子信号处理的理论框架得到了更为通用的量子算法设计模型,指出了量子算法所具有的并行化特性,为算法并行化提供了一种新的思路。     

基于高阶累积量的最大似然估计方法及其应用

讨论了高距离分辨率制导雷达的近距角闪烁抑制问题,提出了利用超分辨谱估计算法对混叠在同一距离分辨单元内的两个或多个散射中心进行离析,然后采用最大似然估计方法分别估计各个散射中心谐波分量幅度与相位信息的新方法.实验结果表明,该方法能够有效克服目标多散射中心之间的干涉现象,为解决末制导过程中目标的稳定跟踪问题提供了一种有效途径.     

滤波器组框架理论及其在图信号处理中的应用

滤波器组框架理论是应用数学、信号处理、图像处理和数字通信等领域的重要问题之一,对滤波器组框架的分析和设计问题进行研究有着重要的科学意义和应用前景.近年来,随着高维非规则化数据信息大量涌现,很多学者开始研究图信号处理的滤波器组方法.因此对滤波器组框架理论及其在图信号处理中的应用进行了综述研究.首先对传统滤波器组框架理论的基础知识进行概述,总结滤波器组框架分析与设计方法;然后重点介绍两类图信号处理架构以及图滤波器组的最新研究成果;最后对未来的研究进行展望.     

An optimum parallel architecture for high-speed real-time digital signal processing

The authors describe a parallel processing architecture for real-time digital signal processing that has demonstrated virtually 100% data processing efficiency in a number of areas. The Teamed-Architecture Signal Processor (T-ASP) is a field-proven, commercially available optimal system solution to the extremely high computational and I/O rates encountered in modern digital-signal-processing environments. The design of T-ASP involves the consideration and implementation of many architectural concepts used to enhance the performance of a computer, including programmability, parallel processing, vector processing and pipelining, memory interleaving, double cache memories, multiple high-speed I/O interfaces, and segmentation of the processors for elimination of both CPU and data-handling overhead. The authors discuss hardware architecture design and implementation; hardware management; and software architecture design and implementation.<>     

利用RapidIO技术搭建的可重构信号处理平台

军事领域常选择ADI公司的TS201芯片用于信号处理平台,但由于其采用基于电路交换的LINK口进行连接,难以实现军方对电子系统设计提出的可重构性的需求。FPGA可以用来实现接口转换功能,如果利用FPGA将基于电路交换的LINK口转换成基于包交换的其他形式的接口,就能在不改变硬件连接的基础上,实现DSP系统的重构。本文介绍了一种基于串行RapidIO技术的可重构的信号处理平台,并对其中核心的FPGA的逻辑设计进行了讨论。     

Parallel processing for biomedical signal processing

The authors describe how systematic mapping methodologies can be used to derive special-purpose processor arrays for the estimation of the bispectrum via the third-order moments. A novel design that is optimal in terms of total execution time for multiple pipelined data blocks is proposed, and it is shown how formal verification of the design can be achieved analytically. The discussion focuses on mapping regular algorithms to parallel architectures, bispectrum estimation from the third-order moments, and systolic array design for the third-order moments     

EMG在语音信号识别中的应用

提出使用肌电信号的语音识别系统。研究证实从面部肌肉中提取的肌电信号存在语音信息。实验使用(0～9)十个数字,受试者每隔10s重复单词。讲话时用电极记录五个通道表面肌电信号。用短时傅里叶变换提取信号的特征量,并通过主成分分析降维,有效地提取特征量进行模式识别。分类错误范围在15%以下。实验表明表面肌电信号的语音识别系统有着极好的前景。     

An application of system identification in metrology

Metrology is advancing by development of new measurement techniques and corresponding hardware. A given measurement technique, however, has fundamental speed and precision limitations. In order to overcome the hardware limitations, we develop signal processing methods based on the prior knowledge that the measurement process dynamics is linear time-invariant.Our approach is to model the measurement process as a step response of a dynamical system, where the input step level is the quantity of interest. The solution proposed is an algorithm that does real-time processing of the sensor's measurements. It is shown that when the measurement process dynamics is known, the input estimation problem is equivalent to state estimation. Otherwise, the input estimation problem can be solved as a system identification problem. The main underlying assumption is that the measured quantity is constant and the measurement process is a low-order linear time-invariant system. The methods are validated and compared on applications of temperature and weight measurement.     

An automatic/controlled processing theory application to training component map reading skills

An experiment was conducted which explored the applicability of automatic/controlled processing theory to a complex map reading/identification task. Subjects were trained on one component of a map reading task (magnitude estimation based on map-legend colour codes) and then transferred to a full map reading mask. Consistent and inconsistent colour codes were trained. Training with consistent map-legend colour codes resulted in automatic processing of those codes and led to performance that was faster, less variable and less sensitive to memory factors when compared with performance associated with variably mapped colour codes. These data support the view that consistent hierarchical relationships can be utilised to supersede inconsistencies at the individual stimulus level. The results also place constraints on how displays should be built in order to capitalise on hierarchical consistencies held in memory.     

An adaptive notch filter for frequency estimation of a periodic signal

Online frequency estimation of a pure sinusoidal signal is a classical problem that has many practical applications. Recently an ANF with global convergence property has been developed for this purpose. There exist some practical applications in which signals are not pure sinusoidal and contain harmonics. Therefore, online frequency estimation of periodic but not necessarily sinusoidal signals espoused by such applications becomes quite important. This note presents an alternative stability analysis for a modified ANF that permits the presence of harmonics in the incoming signal. Also, this stability analysis is simpler and alleviates the problem complexity even in the case of pure sinusoidal signal. Simulation results confirm theoretical issues.