Analysis and simulation methods for performance evaluation of a multiple networked embedded architecture

This paper deals with the modeling and the validation of multiple networked embedded computer systems supporting in-vehicle applications. In this context, the authors developed a modular modeling and simulation technique. This approach allowed the development of reusable component models with clearly defined interfaces. The building of a whole application model is then obtained by the integration of these components, so that model construction and result analysis are made easy. In fact, thanks to the formal definition of components, interfaces, and composition rules, this step is automatically achieved. In the context of the CAROSSE project, we implemented this methodology in the Carosse-Perf tool. Herein, the authors detail the methodology together with its modeling principles and the resulting definition of basic components and interfaces. Finally, they apply it to a case study drawn from a PSA Peugeot-Citroen application.     

Synthesis of modular mechatronic products: a testabilityperspective

Producing modular products that combine modules with the consideration of product performance, e.g., testability of electronic systems, is frequently stated as a design goal. However, most of mechatronic frameworks (models) discussed in the literature do not consider testability of electronic subsystems of mechatronic products. This paper assumes that the product modules have been established, and aims at the development of modular mechatronic products with the consideration of testability of electronic subsystems as a performance criterion. The generation of modular products and module testability issues are discussed. Testability points, testability values, and access paths for a module/system are crucial to the generation of modular mechatronic products. A generalized label-correcting algorithm is developed to determine the points of focus, testability values, and access paths in modules     

基于MATLAB/Simulink的异步电机控制系统建模与仿真

本文在基于转子磁链定向的异步电机矢量控制理论基础上,针对磁链闭环的矢量控制系统中转子磁链易受电机参数影响的不足,提出了转子磁链开环的矢量控制方案。利用模块化思想,在MATLAB/Simulink建立磁链开环的矢量控制系统的各个功能模块,然后对各个功能模块进行有机的整合,构成矢量控制系统的仿真模型;仿真结果表明该系统具有良好的动态性能和抗干扰能力,进而验证了该控制系统设计的可行性和有效性,为实际电机控制系统的设计和调试奠定了理论基础。     

The application of COTS technology in future modular avionicsystems

Current avionic systems make extensive use of military specifications and standards but are based on dedicated implementations for individual avionic functions. The result is a proliferation of military devices, software and support environments that are expensive to develop, procure and support. Future systems will be based on integrated modular avionic concepts in which all functions are implemented on a common processing platform constructed from a standard set of hardware and software modules. The paper describes the approach being taken to optimise the application to future modular systems: an architecture based on standardised interfaces will allow modules to be based on commercial components and standards to achieve affordability and exploit rapid advances in commercial technology. At the same time, approaches are being developed to deal with COTS (commercial off-the-shelf) application problems such as short commercial time-scales and loss of control over specifications and standards     

A New Nonbinary Matrix Clustering Algorithm for Development of System Architectures

Clustering techniques have been widely used for solving various engineering problems such as system architecture, modular product/system design, group technology, machine layout, and so on. Most of these problems use matrix formulation to model the problem. Once the matrix formulation for the problem is obtained, cluster analysis is used to group objects represented in the matrix into homogenous clusters based on object features. In this correspondence, a new efficient algorithm for clustering large n x n binary and nonbinary (weighted) matrices is presented. For an n x n incidence matrix, the algorithm first creates n clusters. Once the initial clusters are obtained, the algorithm uses improvement steps to continuously improve the quality of the solution obtained in the previous step. Modifications to the algorithm are presented for clustering n x m matrices. A detailed discussion on the effectiveness of the clustering algorithm when it is applied to matrices of various sizes and sparsity is also presented. The application of the n x n clustering algorithm developed in this correspondence is presented with the development of modular electrical/electronic vehicle door architectures.     

GPON系统中OMCI管理方案设计(本期优秀论文)

OMCI协议是GPON系统中实现OLT对ONU控制管理的标准协议,实现OMCI协议的管理方案设计成为一个核心问题.本文介绍了OMCI协议功能,根据模块化设计思想,对OLT和ONU中的OMCI功能模块进行设计,最后在OMCI模块设计的基础上,给出OMCI消息在OLT和ONU各模块之间的处理流程.     

一种OPNET网络仿真与实物终端的互联实现

针对网络研究中纯数学网络仿真建模难以保证准确度的问题,研究了基于OPNET软件的网络半实物仿真模型。讨论了半实物仿真系统的构成,分析了系统各模块的功能,提出了OPNET半实物仿真系统的模块化设计方案,详细讨论了半实物仿真硬件处理接口单元和软件处理接口单元的实现,并分析了仿真系统的运行结果。通过实例证明半实物仿真在网络研究中具有技术优势。     

System-level reliability assessment of mixed-signal convergent microsystems

The next-generation convergent microsystems, based on system-on-package (SOP) technology, require up-front system-level design-for-reliability approaches and appropriate reliability assessment methodologies to guarantee the reliability of digital, optical, and radio frequency (RF) functions, as well as their interfaces. Systems approach to reliability requires the development of: i) physics-based reliability models for various failure mechanisms associated with digital, optical, and RF Functions, and their interfaces in the system; ii) design optimization models for the selection of suitable materials and processing conditions for reliability, as well as functionality; and iii) system-level reliability models understanding the component and functional interaction. This paper presents the reliability assessment of digital, optical, and RF functions in SOP-based microsystems. Upfront physics-based design-for-reliability models for various functional failure mechanisms are presented to evaluate various design options and material selection even before the prototypes are made. Advanced modeling methodologies and algorithms to accommodate material length scale effects due to enhanced system integration and miniaturization are presented. System-level mixed-signal reliability is discussed thorough system-level reliability metrics relating component-level failure mechanisms to system-level signal integrity, as well as statistical aspects.     

Run-Time Integration of Reconfigurable Video Processing Systems

Embedded systems in field-programmable gate arrays (FPGAs) can be customized and adaptive if assembled from modular components at run time. This paper examines realizing run-time system assembly by extension of platform-based design. Two major challenges are addressed in this paper. First, the design of a reconfigurable platform architecture suitable for run-time system assembly is described. Different systems are constructed by integrating the platform architecture with different modular components, which employ the communication infrastructure supplied by the platform in order to interact. Second, where on-chip communications channels use shared media, we propose techniques for modeling the intermodule communication behavior based on statistical time-division multiplexing. The proposed techniques enable system designers to guarantee that logical communication requirements between the adjunct modules can be satisfied by the infrastructure. An in-depth analysis is presented and then verified with cycle-accurate simulations for an example reconfigurable platform for real-time video applications.     

Software implemented fault tolerance: A methodology

A methodology for fault tolerance is proposed. This is based on the interactions between hardware and software in a scheme made of intelligent modules. This is particularly applicable to VLSI systems. Particular emphasis has been posed on the software implementation to reduce the external hardware, as this is the main source of hard core failures. A design of a duplex hybrid system with software implemented fault tolerance is presented to evidentiate the novel characteristics of this approach.     

软件无线电技术在卫通终端中的应用

根据软件无线电技术的思想,提出了一种依托通用的可编程硬件平台,以各种软件模块实现不同标准信号通信的多速率、多模式的卫星通信终端的设计。详细讨论了该设备的软、硬件结构设计,并对所涉及的开放式的总线结构、宽带A/D、D/A转换技术、高速数字信号处理技术、功能软件模块化编程设计等关键技术进行了分析。     

星载SAR功能结构一体化天线技术研究

提出了新型低剖面合成口径雷达(SAR)有源相控阵天线设计方法———多功能结构一体化天线技术,采用高密度互联、新型功能材料等进行模块化、轻量化的系统级集成设计,将系统功能与天线结构相结合,大幅减小了SAR天线的体积,增大了内部可用空间;同时,有效去除天线寄生质量及各分系统间的重复质量。对SAR天线进行了一体化设计验证,结果表明天线性能、结构承载及热控的指标满足要求,多功能结构一体化设计方法对大型有源相控阵天线系统的结构设计有实际指导意义。     

Functional Validation of Mixed Hardware/Software Systems based on Specification, Partitioning, and Simulation of Test Cases

Tecs is a test case development methodology for the functional validation of large electronic systems, typically consisting of several custom hardware and software components. The methodology determines a hierarchical top-down test case development process including test case specification, validation, partitioning and implementation. The test case development process addresses the functional validation of the system and its components such as ASICs, boards, HW and software modules; it does not facilitate timing or performance verification. The system functions are used to define test cases at the system level and to derive sub-functions for the system components. Test cases are specified, using a special purpose formalism, and validated before they are applied to the system under test. Furthermore, we propose a technique to partition test cases corresponding to the partitioning of the system into sub-systems and components. This technique can significantly reduce system simulation time because it allows the full validation of system functions by simulation at the sub-system and component level. The system model need only be simulated with a reduced set of stimuli to validate the interfaces between sub-systems. We present a test case specification language and tools that support the proposed methodology. The validation of a switching function illustrates methodology, language, and tools.     

ELSA: a multisensor integration architecture for industrial grading tasks

This paper presents the topology of the Extended Logical Sensor Architecture (ELSA) for multisensor integration and the methodology for constructing industrial sensor integration systems based on this architecture. ELSA has been developed for industrial applications, particularly, the on-line grading and classification of non-uniform food products. It addresses a number of issues specific to industrial inspection. The system must be modular and scalable to accommodate new processes and changing customer demands. It must be easy to understand so that non-expert users can construct, modify, and maintain the system. Furthermore, a data representation scheme which allows for the quantification of product deviations from an ideal model is required.To address these needs, the sensors are encapsulated by a logical sensor model, providing robustness and flexibility. The construction methodology is based upon the object model which represents object classifications through combinations of primary features weighted by fuzzy membership functions. The features guide the selection of sensors and processing routines; the classifications determine the rulebase used by the inference engine for process decisions. Although inspection is the focus of this work, it is intended to be applicable to a variety of automation tasks which may benefit from a multiple sensor perception system.     

Cost and performance tradeoff analysis in radio and mixed-signal system-on-package design

An optimal total solution for radio and mixed-signal system integration needs tradeoffs between different design options. Among various design metrics, cost and performance are probably the two most important factors for design decisions. In this paper, we review and analyze cost-performance tradeoffs of system-on-chip (SOC) versus system-on-package (SOP) solutions for radio and mixed-signal applications. A new design methodology, which quantitatively predicts performance and cost gains of SOP versus SOC, is presented. The performance model evaluates various mixed-signal isolation techniques between sensitive analog/RF circuits and noisy digital circuits in SOC or SOP. The cost analysis includes new factors such as extra chip area and additional process steps for mixed-signal isolation, seamless integration of "virtual components" or intellectual property (IP) modules, yield and technology compatibility for merging logic, memory and analog/RF circuits on a single chip, and extra costs for moving passives off chip. In addition to these, a complete and systematic analysis method for on-chip versus off-chip passives tradeoffs is presented. The analysis and modeling techniques explore tradeoffs between performance, cost, robustness, and yield when different on-chip or off-chip passives are used. It thus provides a complete picture of quantitative tradeoffs for using on-chip or off-chip passives. The design methodology and analysis techniques are then demonstrated through several design examples in wireless applications. It is clearly shown that for all complex and high performance mixed-signal systems, SOP is a lower cost solution than SOC. Finally, some design guidelines for SOC versus SOP and on-chip versus off-chip are concluded.     

A Composite Software Design for the Electronic Switching System

This paper describes a process to achieve modular software for switching systems in a way similar to hardware design manufacturing the components first, then constructing a system using the components needed. To reduce the software maintenance cost in the case of changing switching functions, the following factors were studied: 1) modularity corresponding to divided switching functions; 2) interface standardization among the modules; 3) software structure applicable to different systems. In the trial manufacture for the data switching system, the authors were able to reduce manpower required for designing and debugging, and were able to obtain a structural simplicity and modular portability to other switching systems.     

ISDN终端系统驱动程序的实现

为了优质,高效地编写ＩＳＤＮ驱动程序,我们在相关产品的开发过程中,采用了构造软件模块的编程方法。通过驱动软件,协议程序,编程接口的适当组合,能够迅速开发出具有全新功能的硬件方案或软件程序,软件模块构造方案以ＣＡＰＩ为基础,提供与具体硬件相关的实现方案。