支持高性能应用的SRAM

SRAM一直是网络应用的重要组成部分，它可提高带宽，从而在许多高性能应用中起着主导作用。这些应用包括无总线时延(NoBL)和四倍数据速率(QDR)等。就系统资源及内存带宽要求而论，分组处理对内存带宽的要求最高。分组处理块内部的多个功能以及其它存储功能要求采用不同的SRAM架构。     

高性能系统中存储模块的验证

对很多工程师来说,高速存储模块的设计和验证已经成为一项重大的挑战。较早的存储器产品(如EDO、FPM和SDRAM)由于工作在较低的系统总线速度下,其时序上留出的裕量,足以让系统和模块设计指标有更宽的松动范围。而现在,由于存储器和I/O必须在400MHz以上的速度工作,电气指标的容许变化范围变得比以前小得多。在具体的时序指标、电气指标和机械指标等方面,必须满足严格的设计规则和参数要求,以便让整个系统保持平衡。在Intel的PC66规范推出以前,由于器件之间的差异和业界共同标准的缺乏,能在这一个系统中正常工作的模块在另一个系统中却…     

High Performance CMOS Transconductor for Mixed-Signal Analog-Digital Applications

This paper describes a CMOS building block dedicated to high performance mixed analog-digital circuits and systems. The circuit consists of six MOS transistors realizing a new wideband and tunable transconductance. The theory of operation of this device is presented and the effects of transistor nonidealities on the global performances are investigated. Use of the proposed circuit to realize tunable functions (Gm-C filter and current opamp) is illustrated. HSPICE simulations show a wide tuning range of the transconductance value from 40 S to 950 S (500 S) for ±2.5 V (±1.5 V) supply voltages. The transconductance value remains constant up to frequencies beyond 500 MHz. The bandpass filter built with few transconductance blocks and capacitances was simulated with ±2.5 V supply voltage, the center frequency is tunable in the range of 30 MHz to 110 MHz. However, the opamp, which is designed with a transresistance-transconductance architecture, was simulated with ±1.5 V supply voltage. The gain of the opamp can be tuned between 70 dB and 96 dB and high gain-bandwidth product of 145 MHz has been achieved at power consumption of less than 0.5 mW. Experimental results on a fabricated transconductor chip are provided.     

High Performance Data Broadcasting Systems

Data broadcasting as a means of efficient data dissemination is a key technology facilitating ubiquitous computing. For this reason, broadcast scheduling algorithms have received a lot of attention. However, all existing algorithms make the core assumption that the data items to be broadcast are immediately available in the transmitter's queue, ignoring the key role that the disk subsystem and the cache management play in the overall broadcast system performance. With this paper we contribute a comprehensive system's perspective towards the development of high performance broadcast systems, taking into account how broadcast scheduling, disk scheduling, and cache management algorithms affect the overall performance. We contribute novel techniques that ensure an efficient interplay between broadcast scheduling, cache management, and disk scheduling. We study comprehensively the performance of the broadcast server, as it consists of the broadcast scheduling, the disk scheduling, the cache management algorithms, and the transmitter. Our results show that the contributed algorithms yield considerably higher performance. Furthermore, one of our algorithms is shown to enjoy considerably higher performance, under all values of the problem and system parameters. A key contribution is the result that broadcast scheduling algorithms have only a small effect on the overall system performance, which necessitates the definition of different focal points for efforts towards high performance data broadcasting.     

高性能微处理器及其应用

本文介绍了一种目前通信和网络市场上最先进的高性能集成通信微处理器PowerQUICCⅡ,结合国内通信设备制造商开发重点从传统线路交换设备全面向数据通信和网络设备转移的背景,提出尽快掌握PowerQUICCⅡ高性能微处理器的应用,构建以PowerQUICCⅡ为基础的智能网络平台,有助于提高产品开发速度和升级换代的能力,加快产品进入市场的步伐。     

热成像系统性能分析中的参量归一化空间

根据线性滤波理论，讨论了热成像系统性能分析中的参量归一化空间，分析了软件设计和使用时易出现的错误，提出了适合的处理方法，对于避免使用上的人为失误有积极意义。     

远程嵌入式应用的丰富图形界面

通过Internet远程访问嵌入式应用系统进行监测或控制的方式,大大方便了最终用户,并为他们节省了成本和时间.通过连接以太网总线和访问Internet,受限于线缆长度的通信距离问题不复存在了.此外,这种方式可以实现远程图形交互功能,降低了开发难度和硬件成本,并且可以通过遍及全球的浏览器进行访问.     

高可靠性电源系统的热插拔原理和应用

热插拔的工作原理 热插拔（Hot Swap、Hot Plug、Hot Dock）是指在系统导电的工作状态下,将模组、卡或连接器插到系统上而不影响系统的操作。     

单频激光器在空间和高空飞机上应用的最新进展

激光雷达应用于地基、空基和太空基项目可以实现以前难以完成的对地球和行星的科学测量。我们采取的策略是,对于这种系统需要的激光发射机先集中发展环境适用性的原型机,这种设计在用于太空基项目之前可以先通过外场的地基和空基远程传感系统来验证。正是应用此种策略。我们发展了种子注入的单频激光器。下一代空基和太空基激光雷达系统将大量需要这种激光器。本文描述了用于非承压的高空飞机的最新型号单频Nd：YAG激光器。激光器可以产生两束200Hz、20W、1064nm的输出光束,其中一条光束的输出路径设有温控箱,保存用于倍频和三倍频的非线性晶体。     

High Performance Static Segment On-Chip Memory for Image Processing Applications

The performance of the processor core depends on the configuration parameters and utilization of on-chip memory in multimedia applications such as image, video and audio processing. The design of the on-chip memory architecture is critical for power and area efficient design without compromising quality in data-intensive computing applications. This paper proposes a design of high speed, area, and energy efficient Static Segment On-Chip (SSOC) memory for error-tolerant applications. In this static segment method, n-bit data array is reduced by m-bit data array for significant value of input data to achieve balanced design metrics at the cost of accuracy. The proposed m-bit static segmentation algorithm is implemented and verified in Single Port Static Random Access Memory (SP SRAM) architecture for the approximate computing applications. From the overall simulation results, the proposed 4-bit SSOC SP SRAM design provides 49.02% area savings, 50.62% power reduction and 16.92% speed improvement at the cost of 0.64% Peak Signal to Noise Ratio (PSNR) and exhibits same visual quality in comparison with the existing 8-bit conventional on-chip SP SRAM design in the image processing applications.     

High Performance Reversible Direct Data Synthesizer for Radio Frequency Applications

Mobile Networks and Applications - Design of Reversible logic gate enabled Reconfigurable Direct digital synthesizer is evaluated here. The need for Direct Digital Synthesizers (DDS) inherently...     

MICROCOUPLER为高温应用提升功耗性能

光耦合器是具有绝缘安全性及在输入和输出之间实现电气信号隔离功能的器件，其绝缘和噪声抑制特性来自于采用的机械结构和材料。     

Insurance for Space Systems

This paper describes the practice of insurance of commercial communications satellites. A historical review of the insurance of previous satellites is included, starting with the initial Comsat coverage of Intelsat satellites and continuing with the coverage of domestic communications satellites of the United States and other administrations. The types of insurance offered and their typical associated rates are discussed, together with an explanation of the coverage, premiums, and losses which have occurred to date. In the wake of the 1984 losses, estimates are provided of the currently available rates. The characteristics associated with direct broadcasting (heavy and expensive spacecraft, large deployable solar arrays, and high-power transmitters) will affect the future insurance rates for these satellites.     

High Performance Significance Approximation Error Tolerance Adder for Image Processing Applications

Addition is one of the fundamental arithmetic operations which are used extensively in many VLSI systems such as microprocessors and application specific DSP architectures. In this paper, the Significance Approximation Error Tolerant Carry Select Adder (SAET-CSLA) is constructed, which is efficient in terms of accuracy, power and area. While considering the elementary structure of an image processing applications, it is a combination of the multipliers and delays, which in turn are the combination of the adders. This research paper describes the Algorithmic strength reduction technique which leads to a reduction in hardware complexity by exploiting the significances. This transformation is basically implemented for the reduction in the power consumption and area efficient of Very Large Scale Integration (VLSI) design or iteration period in a programmable Digital Signal Processing (DSP) implementation. The significance approximation error tolerant adder is designed using full adder and approximate full adder cells with reduced complexity at the gate level. The performance of 16 bit conventional Carry Select Adder (CSLA), 16 bit Error Tolerant carry select Adder (ET-CSLA) and proposed Significance Approximation Error Tolerant Carry Select Adder (SAET-CSLA) are compared. For all the 2¹⁶ input combinations, comparison is made between existing and proposed CSLA adders and the error tolerance analysis is carried out for accuracy improvement. Application of image processing is carried out using proposed SAET-CSLA.     

从DSP与SBIRS空间预警系统看多色焦平面阵列的应用

空间预警系统（SEWS）是美国弹道导弹战略防御体系（BMD）中不可缺少的组成部分,是一个高度集成、高精度的光机电一体化系统。文章以美国DSP和SBIRS空间预警系统为例进行分析,并根据多色红外焦平面的工作原理,探讨了多色红外焦平面器件在空间预警系统中的应用前景与可行性。DSP和SBIRS空间预警系统具有多波段（红外）的探测能力,其中2．7μm和4．3μm的波段探测采用不同材料的红外焦平面来完成,并具有相应的成像系统,这必然会提高系统的效率和结构的精简。文中以提高空间预警系统的效率为出发点,对采用多色红外焦平面替代多种单色焦平面完成多波段探测的可行性进行了论述。     

高性能模拟前端AD7714及其应用

AD7714是一个完整的用于低频测量应用的模拟前端。其主要特点是:使用Σ-Δ转换技术,转换精度高;具有片内可编程增益放大器和低通数字滤波器;具有SPI通信接口等。通过实验,提炼出了AD7714技术说明书中没有明确的特性和技术指标,纠正了其中的错误,讨论了在应用上的技术要点、缺点,介绍了在“863”重点引导项目和安徽省“十五”重点攻关项目中的应用。     

一种高性能纠错码及其在通信技术中的应用

LDPC(低密度奇偶校验码)码是近年来受到广泛关注的新一代高性能纠错码。该码逼近香农限,易实现,系统复杂度低,对提高数字通信的性能具有重要意义。文中首先对纠错编码的发展进行了系统回顾,然后着重介绍了LDPC码的基本原理、结构与编码方法,并与其他编码方法的性能进行对比,最后概括了目前国内外的研究现状,介绍了LDPC码在通信技术领域中的各种广泛应用。     

Selection Combining Site Diversity Performance in High Altitude Platform Networks

High altitude platform networks operating in Ka-bands and V-bands exhibit severe degradation due to multiple atmospheric phenomena. In such frequencies, site diversity is a very efficient fade mitigation technique. This letter introduces a novel physical analytical model for the evaluation of selection combining site diversity error performance, taking into account the spatial correlation of rain attenuation and the total attenuation statistics. The outage performance of selection combining reception is being calculated through exact close-form formulas. Numerical results highlight the significant improvement against single site reception and determine the optimum relative positioning of main and diverse sites.     

Performance of High Speed Coherent Optical Communication Systems

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