Interpolation filters for 2-D hexagonally sampled signals

This paper deals with the design of interpolation filters for 2-D hexagonally sampled signals using multidimensional antimetric wave digital filters. Theoretically there are two essential schemes for the interpolation of hexagonally sampled signals, i.e. interpolations by factor 3 and by factor 4. We show that by exploiting some symmetry properties of the amplitude response, multidimensional antimetric filters are suitable for the design of interpolation filters in both cases. In particular, very efficient design can be obtained for the case of interpolation by factor 4, for which very low hardware cost is required for achieving satisfactory amplitude responses. The paper also compares the behaviours of the designed interpolation filters with those of circularly symmetric filters realized by cascading some antimetric filters. © 1997 John Wiley & Sons, Ltd.     

Digital processing of EEG signals

The digitization of electroencephalogram (EEG) signal data is the essential first step in using computers to analyse and manipulate EEG data. EEG signals are inherently complicated due to their nonGaussian, nonstationary, and often nonlinear nature as shown by most of the articles of this special issue. On top of that, the small amplitude of these signals reinforce their sensitivity to various artifacts and noise sources. The aim of this special issue is to shed light onto the recent digital techniques for processing EEG signals ranging from storage and artifact removal to event detection/classification and prediction issues     

A course in parallel processing

This paper is intended to help instructors in universities without supercomputer facilities to teach a senior- or graduate-level course on parallel processing. It outlines how supercomputing centers can be accessed, how simulation packages can be obtained, how the course and its laboratory can be organized, and recommends a set of projects, textbooks, and articles that could be used in the course     

An undergraduate parallel processing laboratory

A modest transputer laboratory was established at the Electrical Engineering Department, Louisiana Tech. University. This laboratory is used to introduce undergraduate electrical engineering students to parallel processing. The author discusses course development and then describes five laboratory experiments: introduction to Express, node analysis, event driven profiling, performance analysis, and matrix multiplication     

基于并行NCO的宽带数字下变频器

为了解决当前数字下变频器对硬件处理速度要求过高的问题,设计了一种基于并行NCO的宽带数字下变频器,将并行处理与多相滤波相结合,可以大大降低对处理速度的要求,有效解决数字信号处理的瓶颈问题。仿真结果表明,该宽带数字下变频器成功实现了对数字中频信号的下变频、滤波抽取等功能,输出结果正确,可实现宽带接收处理。     

A real-time digital simulation model of the electromagnetic transients in power transmission systems by parallel processing using multiple modules

Contents Parallel processing has been widely employed in real-time digital simulation of power transmission systems. This paper presents a new model using multiple modules and its integration method. According to this model and the given digital integration method a digital example simulation is carried out covering the following operating phases: electromagnetic and electromechanical transients after connecting a synchronous machine to the idle double-circuit high-voltage three-phase power transmission line (DHTT), automatic synchronization of the synchronous machine at the far end of the DHTT, parallel operation of the power transmission system (a DHTT with synchronous machines at both ends). The results show that the new model is fit for real-time digital simulation of this system.

---

Ein Modell für digitale Echtzeit Simulation der elektromagnetischen Ausgleichsvorgänge in Starkstrom-Übertragunssystemen durch Parallel-verarbeitung mittels Aufspaltung in mehrere Module

Übersicht Bei der digitalen Simulation von Starkstrom-Übertragungssystemen in Echtzeit ist die parallele Datenverarbeitung weit verbreitet. In diesem Beitrag wird ein neues Modell vorgestellt, in welchem das System in mehrere Module aufgespaltet wird, deren Verhalten dann parallel in Echtzeit simuliert werden kann. Eine dazu geeignete Integrationsmethode wird angegeben, mit deren Hilfe die elektromagnetischen und elektromechanischen Ausgleichsvorgänge berechnet werden, die bei der Aufschaltung einer Synchronmaschine auf eine unbelastete Doppelkreis-Hochspannungs-Drehstromübertragungsstrecke (DHTT) auftreten. Außerdem werden die Ausgleichsvorgänge ermittelt, die bei der automatischen. Synchronisation einer am anderen Ende zugeschalteten Synchronmaschine auftreten, und schließlich der Zustand untersucht, wenn beide Enden der DHTT parallel von Synchronmaschinen gespeist werden. Dieses numerische Beispiel zeigt, daß das vorliegende Modell für eine digitale Simulation des Starkstrom systems in Echtzeit geeignet ist.

     

The optimization of spectrum analysis for digital signals

This paper provides a complete method to solve the defects of spectrum analysis for discrete signals. Many researches had issued to deal with the defects of fast Fourier transform (FFT). Those methods may cause the characteristics of original signal altered, or solve this problem in part only. The defects of spectrum analysis cannot be solved efficiently and completely by those methods. These defects result from that those frequency scales cannot match with signal characteristics. This paper is based on the concept to establish a complete solution, divided into three steps: First, this paper analyzes the signal characteristics to be the basis of spectrum adjustment. A simple and accurate algorithm is used to find the frequency and amplitude of each component. Next, this paper finds optimum spectrum parameters to make the new spectrum match with signal characteristics. Finally, this paper takes the parameters to reanalyze the original signal. The method will make spectrum analysis reach optimization. Every procedure in this paper compares with traditional ones to prove its benefits. Moreover, the authors verify the theory feasible by analyzing actual signals.     

基于MATLAB的数字信号的代数插值

通过实验获得的测量信号往往是一系列离散的数据{xi,yi,i=1,2,3…,N,}它们反映了2个物理量之间的函数关系:y=f(x)。当要获知该函数关系中的未知测量值时,常要用到代数插值的方法。本文详细介绍了Lagrange插值,Newton插值和Hermite插值等插值方法的数学原理。通过在MATLAB操作平台上进行算法编程,对一组实验测量信号分别进行3种插值处理,最后比较这些插值方法的优劣。     

Laboratory-based coursework in parallel processing using thetransputer

The design of a low cost, target transputer system is described, along with code development facilities, that allows the concepts of parallel processing to be taught in a practical manner. Outlines of eight graded exercises are also included as an indication of how the system might be used in an undergraduate laboratory     

Thresholding algorithm for local and parallel processing

In this paper, we propose a thresholding algorithm. This algorithm works under a severe constraint: each pixel in a processed image must be derived from only information of its neighboring pixels. This constraint is very important for a low‐cost device such as a mobile camera, because it makes it possible to process each pixel in parallel. The proposed algorithm deals with gray‐scale images, and determines the threshold based on edge information. The proposed algorithm is represented by local and parallel image processing and has been tested using 104 scenery images. The result shows that the proposed algorithm can binarize images. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 157(2): 50–56, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20267     

一种基于UML方式的遥信处理算法

电力系统自动化中RTU得到了广泛的应用.在设计中,由于采用技术的差异, RTU的指标有较大差异.该文描述GEA-2000A RTU中GEA-IRSU遥信单元的设计与实现,重点介绍遥信判断方法的原理.文中首先介绍遥信单元的基本要求.在此基础上,采用UML进行了软件的设计与实现,给出了单元的对象模型和其动态运行序列图.现场运行结果表明,单元的性能完全达到设计的要求.     

Teaching digital image processing with Khoros

As digital image processing has moved into the electrical engineering mainstream, it has become a popular course in the undergraduate curriculum. Since visual perception is a key component of image processing, an effective first course should emphasize laboratory experience. The Khoros software system offers an interactive environment to facilitate such a course     

一种基于UML 方式的遥信处理算法

电力系统自动化中RTU得到了广泛的应用。在设计中,由于采用技术的差异,RTU的指标有较大差异。该文描述GEA 2000ARTU中GEA-IRSU遥信单元的设计与实现,重点介绍遥信判断方法的原理。文中首先介绍遥信单元的基本要求。在此基础上,采用UML进行了软件的设计与实现,给出了单元的对象模型和其动态运行序列图。现场运行结果表明,单元的性能完全达到设计的要求。     

Pontrjagin duality and digital signal processing

All of the Fourier transforms encountered in signal processing can be regarded as instances of a single universal object-the Fourier transform associated with an abstract abelian group. We show how this way of looking at things leads to a natural and simple account of the similarities between the properties of the Fourier transforms associated with different types of signal and how it sheds a new light on the duality between sampling and aliasing     

Fast calculation using parallel processing and pipeline processing in power system analysis

This paper presents an application of parallel processing and pipeline processing to power system analysis. The system matrix is transformed to a bordered block diagonal form (BBDF) matrix for effective utilization of the processors. After LU factorization, subnetworks organize sparse matrices and the boundary network organizes a full matrix. First, a parallel processing technique is used to calculate subnetworks. Then, as pipeline processing is applied, inverse matrix of the boundary network is multiplied. The proposed method is made operational on a parallel computing system including a pipeline processor. A consideration on the transient stability analysis using the proposed method also is presented at the end of this paper.     

Optoelectronic parallel computing using optically interconnectedpipelined processing arrays

We describe our research on optoelectronic parallel computing systems. Our architecture is based on a multilayer pipeline of two-dimensional optoelectronic device arrays in which each pixel is composed of an optical input channel, a general purpose programmable processor, local memory, and a surface-emitting laser diode as an optical output channel. Free-space optics provides parallel, global communication between layers in the pipeline via optical paths which are dynamically reconfigurable. Demonstration systems and some applications are described     

Knowledge-based signal processing in the decomposition ofmyoelectric signals

The mixture of quantitative and qualitative information utilized in decomposition, which suggests that a purely numerical approach to the task would be inefficient, is discussed. The incorporation of symbolic processing methods into the decomposition system to complement the numerical aspects of the task is discussed. The overall philosophy used in the decomposition system is examined, focusing on the principles of detection used. The organization of the software used by the system is described.     

Realization of 3-degree-of-freedom control using fine-grain parallel processing

The article reports a sprout of 3-degree-of-freedom (DOF) control. The limitation of feedback control, including 2-DOF control, has been raised for a long time; however, a suitable control theory for overcoming those limitations has still not been formulated. An underlying reason is that the disturbance-suppression performance and noise sensitivity cannot be decoupled. Several researches have tried to tackle this problem using a hardware approach, as a noise level depends on a hardware configuration. It should be noted that the hardware design expands spatiotemporal resolution of a system. This approach helps in reducing noise, namely, it works as the 3rd-DOF for a control system. Therefore, an improvement in the hardware design could be a new angle for solving a mixed-sensitivity problem. This article quantitatively presents the relation between noise-reduction performance and the spatiotemporal resolution, and provides a foothold for the 3-DOF control.