一种新型软件无线电重构加载方法研究

介绍了一种基于软件无线电平台的重构加载方法,通过研究可重构软件无线电硬件体系结构,FPGA可执行设备重构加载原理、协议及Davinci系列处理器高速并行外部存储器接口(EMIF),提出了一种基于DSP+ FPGA的重构加载方案,实现了FPGA设备驱动和重构加载软件设计.实验结果表明,软件无线电重构加载方案可高速、准确、可靠地完成波形文件重构加载及不同通信模式的无缝切换.     

基于微控制器的程序在线升级设计

针对传统机载系统各级控制器离线程序升级维护周期长、成本高的问题,提出一种基于微控制器的程序在线升级技术方案。首先,介绍了在线串行编程协议。然后,提出基于微控制器程序存储器空间分配机制、程序烧写原理及在线加载方案。最后,利用PC机发送待烧写的可执行程序至微控制器平台,完成了程序在线加载方案的验证。实验结果表明,方案能够实现控制器程序的在线加载,既支持用户编写的程序对程序存储空间进行擦写操作,也支持程序之间的相互跳转。     

TMS320C6701 DSP自动加载研究

在嵌入式系统中,经常要求上电后系统能自动把程序从DSP外部的ROM加载到片内RAM执行.给出一种基于TMS320C6701 DSP的ROM加载方案,通过配置CCS中DSP/BIOS模块的参数实现DSP程序中代码和数据段的先后分开加载,比传统的由手动编写连接命令文件(.CMD)实现自动加载更为方便.在此基础上,设计并实现了用CCS直接对FLASH芯片进行在线烧写.实验证明,该DSP加载方案稳定可靠,且易于实现.     

超快速加载Buck变换器设计

为了提高VRM的加载响应速度,该文分析了传统Buck变换器的最优加载过程,并基于传统Buck变换器提出了双输入Buck变换器电路方案,说明了其稳态工作过程和加载运行过程,以最优加载阈值为依据给出了附加电源的切换条件,并做了仿真对比研究.仿真和试验结果表明双输入Buck变换器较传统Buck变换器具有更快加载响应速度和更小输出电压跌落,且结构简单,易于设计和实现,适用于VRM主电路.     

基于CPLD的FPGA从并快速加载方案

提出了基于复杂可编程逻辑器件(CPLD)的现场可编程门阵列(FPGA)从并加载方案,及逻辑代码的实现过程,并给出仿真结果。该方案理论计算结果表明,当加载SPARTAN-6系列最高端的6SLX150T时,采用基于CPLD的从并加载方式,共需要加载时间为1.221 s,完全满足通信产品的快启动要求,具有较高的应用价值。     

基于串口通信的DSP程序动态加载技术

为解决特殊场合嵌入式设备程序升级困难,提出了一种基于串口的TMS320F2812程序动态加载技术.该方法充分利用F2812丰富的片内存储器资源和支持在线编程特点,采用二级引导方式,通过调用API编程函数对片内FLASH擦除和烧写,实现设备程序的在线加载.实验证明.该方法具有烧写稳定、效率高、操作方便等优点,能够应用于嵌...     

扩展的RBAC权限管理模型的设计与研究

对传统RBAC访问控制模型进行扩展,提出了基于导航树页面的RBAC模型,有效避免了传统RBAC模型应用到B/S系统时的角色和权限冗余.根据大多数电子政务系统对用户与角色数据的读取操作较更新操作频繁的特点,选择LDAP技术存储用户与角色数据,并且完成了数据存储设计.根据XML文件的存储功能以及动态加载导航树控件的特点,实现了基于XML文件权限访问策略的设计.此扩展模型是一种通用的动态加载导航树页面访问控制模型,为开发与设计此类用户访问控制模型的人提供借鉴.     

IPTV机顶盒升级方案的设计与实现

针对目前基于嵌入式Linux系统的IPTV机顶盒(STB)在线升级方案存在系统自恢复方面的不足,通过划分Flash存储器空间和重新设计引导加载程序,改进并设计了一套新的机顶金在线升级方案.实际测试结果表明,本方案可以实现安全稳定的在线升级.     

基于IPSec的VPN网关关键技术研究

针对当前实现VPN网关的主要安全技术,提出了一种基于IPSec协议构建VPN网关的实现方案.该方案采用Linux内核中的Netfilter-Iptables框架结构,结合IPSec协议体系架构以及VPN基本原理,通过对Netfilter框架中IPSec协议的关键模块实现过程分析和加载IP访问控制模块测试实验,实现了基于IPSec的VPN有效控制和高效率连接,实验的结果稳定、安全、可靠.     

基于DVB标准的动态加载数据广播业务的方案实现

主要叙述了数据广播业务的程序代码在CATV网上广播并在机顶盒上"动态加载运行"的方案,基于该方案进一步探讨了在有限资源的STB终端上实现无限的数据广播服务的可行性和巨大的发展潜力.     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks     

Call for Papers—Feature Topic,Vol.12,No.7,2015

正Information Centric Networking Information-Centric Networking(ICN) is an emerging direction in Future Internet architecture research,gaining significant tractions among academia and industry.Aiming to replace the conventional host-to-host communication model by a data-centric model,ICN treats data content as the first