基于C*Core的SoC设计与验证

介绍了基于C*Core的SoC及相应的协同验证平台，提出了一种基于C*Core的SoC软硬件协同设计流程及验证方法，具有降低设计风险和缩短产品开发周期的优点，并给出了一个设计实例。     

基于FPGA的无线传感器网络SoC验证平台设计

基于FPGA的验证平台是SoC有效的验证途径,在流片前建立一个基于FPGA的高性价比的原型验证系统已成为SoC验证的重要方法。针对8位无线传感器网络SoC的设计要求,提出了一种高度集成化的FPGA功能验证平台。描述了以FPGA为核心的SoC验证系统的设计实现过程,并对SoC设计中的FPGA验证问题进行了分析和讨论。该验证平台结构简单,扩展灵活,提高了功能验证的效率和自动程度,缩短了开发周期,保证了SOC设计的可靠性。     

系统芯片FPGA验证系统的软件调试环境设计

软件调试环境是软件与硬件间的桥梁。为了缩短SoC推向市场的时间，必须尽早建立一个好的软件开发调试环境。在SoC系统验证(项目中用FPGA做系统验证)阶段，同时建立软件开发环境，这样软硬件设计就能同步进行，就可以在PFGA上调试软件，缩短SoC的上市时间、降低成本，在FPGA上开发的软件基本可以平移到目标芯片上。本文探索的软件调试环境设计，不需要任何的硬件支持，完全用软件来实现，这又进一步简化了硬件设计，缩短SoC的开发周期和成本。     

片上系统的模型检验

片上系统(SoC)的验证是一个比较复杂的问题，仅靠模拟仿真无法保证SoC设计的正确。形式化方法是利用数学推理的方法来证明其正确．是对SoC设计进行验证的一条重要途径。模型检验技术是一种完全自动化的形式化方法，针对模型检验技术，讨论了在SoC验证中的应用，指出在SoC设计中，只有把模拟仿真与形式化、半形式化的方法结合起来，才能更好的对SoC进行验证。     

一种数模混合SoC的系统级后仿真验证平台

针对传统大规模数模混合SoC后仿真验证过慢的问题,提出了一种数模混合SoC系统级后仿真验证平台。该平台充分利用主流EDA工具,在传统Verilog-cdl后仿真验证平台的基础上,将原本网表中耗时长的模块用Verilog模型替换,使用Verilog-cdl-Verilog仿真方法,明显加快了仿真速度。从验证环境搭建、系统脚本设计、仿真接口设计三个方面详述了仿真平台的设计流程,并通过指令集功能的仿真实现,证明了平台的可行性和可靠性。该验证平台有助于缩短大规模数模混合SoC的开发周期。     

基于ARM7TDMI的SoC芯片的原型验证

验证是SoC（系统芯片）设计的重要环节,FPGA原型验证平台能以实时的方式进行软硬件协同验证,缩短SoC的开发周期,验证系统级芯片软硬件设计的正确性,降低SoC系统的开发成本。本文介绍了基于ARM7TDMI处理器核的SoC芯片设计项目,提出相应的FPGA软硬件协同设计与验证的方案,并在此SoC芯片开发过程中得以实施,取得良好效果。     

将IP集成进SoC

SoC的设计环境, 结合了内部和外部的开发工具，可以创建整个的设计流程，高效而正确地一次完成复杂SoC的设计。整个设计流程包括硬件和软件验证、设计分析、测试、平面计划、布局、定时拟合和详细的物理设计。今天设计一个SoC经常需要有内部开发和外部开发的IP整合。不管IP来源如何,如果要用一种先进的设计方法高效地把它整合到一个SoC之中，同样涉及到 IP 的适当开发。SoC的设计方法在快速发展。下一代加工工艺要求新的工具和流程以适应更小的门长度、先进的金属化连接、更低的电压和更大的芯片电源功率消耗、灵活 I/O 布置、并且…     

系统原型验证平台助力SoC设计

系统原型验证是把IP提前在原型验证平台上验证通过后再进行芯片设计,它支持在FPGA上进行早期软硬件开发和测试验证,可提高SoC设计首次流片即成功的机率,缩短设计周期。     

基于ARM SoC的FPGA原型验证

ARM是目前SoC设计中应用最为广泛的高性价比的RISC处理器,FPGA原型验证是SoC有效的验证途径,FPGA原型验证平台能以实时的方式进行软硬件协同验证,从而可以缩短SoC的开发周期,提高验证工作的可靠性,降低SoC系统的开发成本.     

一种在电路SOC验证接口设计方法研究

SoC已经成为嵌入式系统设计中的关键器件,验证又是SoC设计的关键环节,占用SoC设计过程中60%以上的时间.专用测试设备及JTAG接口等主流SoC验证手段不便于SoC在系统联调时的验证.本文介绍了一种在电路SoC验证接口的设计方法,这种验证方法弥补了主流SoC验证方法在系统验证的不足,提高了SoC验证的效率.     

A Note on Loaded Line Synthesis (Correspondence)

The purpose of this note is to present an alternate derivation of a formula for the synthesis of a loaded line. The problem is to determine the values of the normalized susceptances a and c mounted an exact quarter-wavelength apart along a uniform line. These are arranged in the order a, c, c,. . .c, a to achieve a loaded line with a given phase shift and perfect match. In order to analyze a particular line design for standing-wave ratio and phase shift over a band of frequencies on a digital computer, it is worthwhile to know the values of the susceptances to many more decimal places than one would achieve from a simple graph.     

Filter-embedded design and its applications to passive components

A design in which a filter is embedded in a fiber fixed on a substrate is proposed. It was successfully applied to the fabrication of low loss fiber optic components for a single-mode fiber transmission system. These components have a wide operational temperature range. The design is easily adapted to a multifilter or multifiber component. Filter embedding is achieved in two ways. One is to insert a thin filter chip in a slit which is machined into a fiber fixed on a substrate by a dicing saw (filter inserted type). The other is to evaporate a filter film directly on a fiber end face and butt this fiber to another fiber on a guide groove on a substrate (filter evaporated type)     

Intranet Advantage

In today's business environment companies need to adapt and respond to new business challenges in a rapid but controlled manner, in keeping with their business model. Technology is a key enabler, allowing organisations to respond to changes in their business environment in a managed way. The corporate intranet is a key tool in allowing a company to communicate and operate efficiently. Intranet Advantage was developed as a way to provide a highly customised intranet solution to meet real business needs. It can be rapidly deployed on a customer's site by using preconfigured packages and a suite of optional applications, all of which combine to offer measurable business benefits.     

Sum capacity of Gaussian vector broadcast channels

This paper characterizes the sum capacity of a class of potentially nondegraded Gaussian vector broadcast channels where a single transmitter with multiple transmit terminals sends independent information to multiple receivers. Coordination is allowed among the transmit terminals, but not among the receive terminals. The sum capacity is shown to be a saddle-point of a Gaussian mutual information game, where a signal player chooses a transmit covariance matrix to maximize the mutual information and a fictitious noise player chooses a noise correlation to minimize the mutual information. The sum capacity is achieved using a precoding strategy for Gaussian channels with additive side information noncausally known at the transmitter. The optimal precoding structure is shown to correspond to a decision-feedback equalizer that decomposes the broadcast channel into a series of single-user channels with interference pre-subtracted at the transmitter.     

Lorsque la stratégie du grain de sable et la conformité aux normes freinent ľinnovation

For a company, information and communication system is a product of divergent rationalities which come to clash. Dissimilar logic leads to diverging projects : one focused on information aims to integrate and control its processing and flow rate, the other prefers to look at communication as a vector of working together among peers. However beyond these conflicts appears a factor of coherence and cohesion which ultimately helps the rationalities to join. A management able to combine integration of wage earners by identifying the objectives of the company and individualism (information systems is a vector of such a strategy). The goal is to avoid a major risk in form of mass action. The remaining question turns about the ability for innovation allowed to wage-earners in a company driven by standards and believes, in fact ideology. Sticking to standards, in other words conformity seems to leave out marginal handling and conflicting situation sources of innovative spirit.     

Single-phase to three-phase power conversion interface

This study proposes a single-phase to three-phase power conversion interface which converts the power from a single-phase utility to three-phase power for a three-phase load. The proposed single-phase to three-phase power conversion interface comprises a bridge-type switch set, a set of three-phase inductors, a transformer set and a set of three-phase capacitors. A current-mode control controls the switching of bridge-type switch set, to generate a set of nonzero-sequence (NZS) currents and a set of zero-sequence (ZS) currents. The transformer set is used to decouple the NZS currents and the ZS currents. The NZS currents are used to generate a high-quality three-phase voltage that supplies power to a three-phase load. The ZS currents flow to the single-phase utility so that the utility current is sinusoidal and in phase with the utility voltage. Accordingly, only a bridge-type switch set is used in the single-phase to three-phase power conversion interface to simply the power circuit. A prototype is developed and tested to verify the performance of the proposed single-phase to three-phase power conversion interface.     

并行AVS实时编解码器设计与实现

介绍了一种并行AVS实时编码器的设计,它包括音视频数据输入、音视频编码、传输流系统复用器、输出和控制部分,其中重点介绍了视频编码器和传输流系统复用器的设计和实现.实验结果证明,实现标清AVS实时编码器是可行的.     

Adaptive distribution‐based handover scheme for cellular communication networks

In this paper, we propose a new Generalized Distribution‐Based Handover (DBHO) to deal with the inefficient utilization of spectral resources due to the non‐uniform cell loads. The DBHO scheme is different from the existing adaptive schemes since it uses a new criterion to initiate handover when moving from/to a congested cell. Two risk factors are used to dynamically change handover boundaries according to the distribution of traffic loads. This controls the handover initiation process such that a user in a congested cell that is moving to a free cell is allowed to initiate a handover to a new cell earlier, as long as the signal received from the target cell is higher than a certain threshold. While delaying the handover initiation process for a user moving in the opposite direction, as long as the signal received from the serving cell is not lower than a certain threshold. Our results show a substantial reduction in the handover and call dropouts rates. Our scheme is complementary to the existing adaptive schemes proposed in the literature. The proposed scheme also gives cellular system designers a new tool to optimize the overall network performance by initiating handovers based on the traffic intensities. Frequent handovers increase the load on switching networks, which consequently degrades the Quality of Service (QoS). Existing handover schemes usually use parameters such as the received signal strength for initiating a handover with some additional measurements to reduce unnecessary handovers and call dropouts. These schemes perform well when cell loads are somewhat evenly distributed, but fail to account for nonuniform traffic, as is often the case in microcells. Hence, it is desirable to design efficient handover schemes to avoid unnecessary handovers, reduce call dropouts and yet dynamically adapt to the variation of traffic among cells. In this paper, we present a new adaptive handover scheme that dynamically changes the handover boundaries to balance cell loads and to effectively reduce the average number of handovers. Copyright © 2004 John Wiley & Sons, Ltd.     

“信息论”课程教学方法改革的研究

"信息论"课程具有理论性强、内容抽象和知识点多等特点,本科学生学习容易产生畏惧心理。本文针对性地研究了一套教学改进方案:强化一条主线,营造一个场景;以阶段性目标为牵引,激发学生主动学习兴趣;同时,将全方位教育模式融入到"信息论"教学中,以适应不同学生的需求,平衡深度与广度之间的矛盾。经教学实践,学生学习兴趣普遍提高,教学效果良好。     

Generating series and performance bounds for convolutional codes over burst-error channels

We present an analytical method for evaluating performance bounds for a communication system that employs a convolutional code, a block interleaving with finite interleaving depth, a binary channel that exhibits statistical dependence in the occurrence of errors, and a decoder that implements the Viterbi (1979) algorithm with Hamming metric. The main idea is to apply combinatorial methods to derive a formula for bounds to first-event and bit error probabilities in terms of coefficients of a generating series. The method is used to investigate the tradeoff between coding parameters and interleaving depth to achieve a required performance.