低功耗编译技术综述

功耗问题已经成为制约电子系统发展的重要因素.功耗是由硬件在运行软件时产生的,软件的数据存取和指令执行都会使硬件产生功耗.编译器可以通过适当的调度优化,改变软件在硬件上的运行轨迹,使得硬件执行某一个程序时的功耗变小.本文从如何对软件的功耗进行评估和如何实现低功耗的编译两大方面对低功耗编译的相关研究进行了广泛介绍,着重评述了专门的低功耗编译技术.最后对当前低功耗编译存在的问题做了分析,给出了对于低功耗编译新方向的预测.     

基于硬件构件的嵌入式系统低功耗研究

降低系统功耗不仅要考虑硬件方面的因素,同时也要分析因软件引起的功耗。为了降低系统整体功耗,首先需要明确影响系统功耗的软硬件因素。在硬件方面,通过对硬件构件进行选择、设计和整合等方法降低功耗;软件方面则是重点优化与功耗密切相关的要素,如算法、指令与方法等。这些因素往往是相互制约、相互影响的。设计一个成功的低功耗系统,需要通过分析与实验,明确一个以硬件构件为思想的嵌入式系统低功耗设计时所需考虑的一些问题。     

Android手机低功耗GPS导航软件设计与实现

随着智能手机功能日益丰富完善以及移动互联网的迅速发展,智能手机的功耗管理就显得越来越重要了.传统的关于功耗管理都是从显示屏、网络模块(GPRS/WiFi)和处理器等入手,文中通过优化GPS软件实现低功耗.通过阐述现在导航软件的工作原理并分析手机定位导航功耗情况,最后通过对比测试当前android系统4大主流导航软件功耗情况,并结合自己提出的低功耗编程以及软件运行流程,设计并实现了一款低功耗GPS导航软件,通过测试,验证了该软件的可行性以及低功耗特性.     

低功耗MCU系统软硬件设计考虑

电子产品的低功耗问题经常让产品设计者头痛而又不得不面对.以单片机(MCU)为核心的系统,其功耗主要由单片机功耗和单片机外围电路功耗组成.要降低单片机系统的功耗,需要从硬件和软件两方面人手.     

嵌入式系统低功耗设计研究

在嵌入式系统设计中低功耗设计是许多设计人员必须面对的问题,其原因在于嵌入式系统产品不是一直都有充足的电源供应,往往是靠电池来供电的,而且大多数嵌入式设备都有体积和质量的约束。另外,系统部件产生的热量和功耗成比例,为解决散热问题而采取的冷却措施进一步增加了整个系统的功耗。为了得到最好的结果,在系统设计时就必须考虑低功耗问题。系统的功耗设计涉及到软件、硬件、集成电路工艺等多个方面,这里分析了功耗产生的原因,从原理和实践上探讨系统的低功耗设计问题,综述硬件低功耗和软件低功耗的设计方法,给出实现低功耗设计的一种可行方法。     

嵌入式智能系统底电流的调试方法

本文针对如何获得嵌入式系统低功耗状态下的准确电流值的方法进行了阐述和验证。硬件使用Intel PXA270芯片构成的最小系统为基础,提出了软件先在bootloader中进行系统进入低功耗状态和退出低功耗状态的调试方法。分析了最小系统睡眠时功耗值与配有其它外围设备的嵌入式系统睡眠时功耗值相同的原因。     

嵌入式系统的低功耗设计技术

随着嵌入式系统的广泛应用,低功耗问题摆在了设计人员面前.低功耗设计包括系统设计、硬件设计、软件设计、器件的工艺设计等诸多方面.其中器件的工艺设计主要由半导体器件的厂家来完成,嵌入式系统的应用设计人员只需要关心器件的功耗指标,更多的工作集中于系统的硬件、软件以及它们之间的配合方面.本文主要从这些方面讨论嵌入式系统的低功耗设计问题和设计方法.     

基于C8051F040单片机的便携式心电监护仪的低功耗设计

在便携式心电监护仪器设计中,微处理器是影响系统功耗的重要因素,可以通过对微处理器内部资源的设计来降低整个系统的功耗.C8051F040单片机是一低电压供电(2.7～3.6V),集成度更高,运行速度更快的8位CIP51处理器,因此C8051F040单片机在低功耗系统设计中具有很大优势,在便携式心电监护仪的设计中,我们采取了一系列的硬件和软件措施,系统功耗降低了近30%.     

基于ARM的便携式系统的功耗管理

ARM微处理器因其高性能和低功耗的特性,特别适合于便携式系统的应用。而系统级的问题对于有效的功耗管理也是非常重要的。本文主要对硬件及系统的功耗管理作一些介绍。功耗管理电路能尽可能地降低便携式系统的用电量。最主要的优点是延长电池的使用寿命,当然还有其他一些优点,如减少散热量等。充分了解系统各部分组件的耗电情况、降低系统哪部分耗电量比较合理等问题是至关重要的。图 1 所示为PDA类产品的功耗分布情况。功耗管理是由软件、处理器、外设、电源等一起构成的系统问题。处理器便携式系统的处理器中有大量与系统其他电路相连…     

Silabs MCU低功耗优势及其实现方法

现在的电子产品，对低功耗的要求越来越高。产品功耗的问题是经常让产品设计者头痛而又不得不面对的一个问题。以单片机为核心的系统，其功耗主要由单片机功耗和单片机外围电路功耗组成。要降低单片机系统的功耗，需要从硬件和软件两方面入手。     

Technology innovation and process integrations for sub-100nm gate patterning

This paper presents a brief overview of the Applied Centura(R)DPS(R)system,configured with silicon etch DPS Ⅱ chamber, with emphasis on discussing tuning capability for CD uniformity control. It also presents the studies of etch process chemistry and film integration impact for an overall successful gate patterning development. Discussions will focus on resolutions to key issues, such as CD uniformity, line-edge roughness, and multilayer film etching integration.     

Complete approach to automatic identification and sub-pixel center location for ellipse feature

To meet the need of automatic image features extraction with high precision in visual inspection, a complete approach to automatic identification and sub-pixel center location for similar-ellipse feature is proposed. In the method, the feature area is identified automatically based on the edge attribute, and the sub-pixel center location is accomplished with the leastsquare algorithm. It shows that the method is valid, practical, and has high precision by experiment. Meanwhile this method can meet the need of instrumentation of visual inspection because of easy realization and without man-machine interaction.     

White organic light-emitting devices based on fac tris（2- phenylpyridine） iridium sensitized 5,6,11,12-tetraphenylnap -hthacene

We have fabricated the white organic light-emitting devices （WOLEDs） based on 4,4＇ -bis（2,2 -diphenyl vinyl）-1,1＇ - biphenyl （DPVBi） and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene （rubrene）. The device structure is ITO/2T-NATA （20 nm）/NPBX （20 nm）/CBP： x%Ir（ppy）3：0.5% rubrene （8 nm）/NPBX （5 nm）/DPVBi （30 nm）/Alq（30 nm）/LiF（0.5 nm）/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris （2-phenylpyridine） iridium [Ir（ppy）3], acts as a yellow light-emitting layer, and N,N＇ -bis- （1-naphthyl）- N,N＇ -diphenyl -1, 1＇ -biphenyl-4,4＇ -diamine （NPBX） acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir （PPY）3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V.     

小角度扩展相关性近似算法分析

本论文提出一种在多天线MIMO信道相关性建模中小角度扩展近似理论算法,并应用于分析MIMO系统性能。分析中分别对三种不同角能量分布情况下的空间相关性研发快速近似计算法,并同时提出双模(Bi-Modal)角能量分布情况下的近似运算。通过分析这些新方法的近似效率,可以得到计算简单、复杂度低、而且符合实际的MIMO相关信道矩阵,对系统级的快速高效计算法的研究和系统级的评估以及误差分析具有重要的意义。     

A Versatile Mixed-Signal Pin Approach for Cost-Effective Test of Automotive ICs

Integrated circuits (ICs) intended for increasingly sophisticated automotive applications bring unique test demands. Advanced ICs for applications such as highly integrated automatic braking system (ABS) and airbag controllers combine high voltage digital channels, significant VI demands and precise timing capability. Along with continued missioncritical reliability concerns, the trend toward higher voltage operation and increased device integration requires specialized test capabilities able to extend across the wide operating ranges found in automotive applications. Among these capabilities, automotive test requirements increasingly dictate a need for a cost-effective versatile mixed-signal pin electronics with very high data rates reaching up to 50MHz with a voltage swing of-2 V to +28 V.     

Optical vibration and deviation measurement of rotating machine parts

It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essential of this method is an image derotator combined with a high speed camera or a laser doppler vibrometer （LDV）.     

社长序言（英文）

正Happy New Year!As we step into a new year,we take a look back at the key feature topics covered in China Communications over the past 12 months and set out our expecta-     

Call for Papers

正Introduction Jointly sponsored by the China Institute of Communications(CIC)and the IEEE Communications Society(IEEE ComSoc)since the year 2013,China Communications,currently,is aiming to gradually realise the transition from journal to magazine content and style.     

INTEGRATION OF OPTICAL AND WIRELESS NETWORKS

正For a long time,optical and wireless systems/net-works are developed in separate communities witha few attempts for in-depth convergence.In fact,it prom-ises many advantages to combine the optical and wire-less technologies in the levels of systems and networks.Recently,both academia and industry have made manyefforts to enter a new phase of development to take op-tical and wireless systems as fully integrated networks.To provide high bandwidth and reliable service for bothfixed and mobile users,a well-designed network must     

Call for Papers—Feature Topic,Vol.12,No.3,2015

正Smart Grid Communications The electric power industry is undergoing profound changes as the industry aims to capture the promise of a smart grid for a sustainable energy future.Enabled by the advanced sensing devices such as Phasor Measurement Units(PMUs),increasingly powerful