基于Bluetooth''s SPP应用框架的文件传输技术的研究与实现

文中对蓝牙的一个通信应用框架--SPP进行了细致的分析,并基于PC上的LINUX系统给出了一个应用实例,着重介绍了SPP应用框架下链路的建立以及通信的机制,最后通过CSR公司的BC04模块进行了性能测试,实现了两个蓝牙设备之间的文件的传输,证明了SPP层文件传输速率远高于FTP层文件传输速率.     

列车感应通信信道的建模分析

首先建立了具有屏蔽导体的多导体传榆线和地面上方单传榆线的数学模型，在此基础上建立列车感应通信信道的模型，并利用矩量法进行数值分析。     

基于蓝牙模块的嵌入式系统设计

蓝牙作为一种时尚的通信方式,近年来应用范围越来越广泛,具备蓝牙功能已成为许多电子产品吸引用户的一大亮点。首先简要介绍了蓝牙技术以及它的核心协议和应用框架,在此基础上提出了一种基于单一蓝牙模块的嵌入式系统开发方法;具体给出了蓝牙模块与单片机的通信方案,并对此方案的硬件结构和软件结构作了详细阐述;最后对此系统进行了测试。测试结果达到了预期的效果,两台蓝牙设备之间可以顺利实现数据通信。采用这种开发方法,可快速开发出具有蓝牙功能的产品。     

蓝牙技术讲座 第2讲 蓝牙系统结构

本文介绍了蓝牙的系统结构组成，并对蓝牙系统结构中的无线与基带层，链路控制器及逻辑控制与自适应协议层，主机控制器接口层和应用框架与支持层的基本概况作了较详细的论述。     

蓝牙耳机应用模型在PC机上的实现和应用

基于蓝芽技术的应用模型有很多种,文章讲到的蓝牙耳机应用模型（Headset Profile）就是其中的一个,它依赖于蓝牙应用规范中的2个通用的应用模型GAP（通用访问模型）和SPP（串口应用模型）。文章给出了蓝牙耳机应用的基本概念及其应用模型并在PC机上实现了该应用,该应用使用户摆脱了电缆线（耳机线）的束缚,能够在较大的自由空间内通话。     

基于蓝牙技术的粉尘检测器的设计

文中以新华龙公司的C8051F020为主控芯片和第一代蓝牙模块芯片BCM-05为通信模块,设计一个蓝牙空气粉尘检测器,使之与蓝牙接入设备搭建一套用于工业控制领域的的空气粉尘检测系统。文章给出了该蓝牙粉尘检测器的硬件设计和该系统的软件框架。硬件设计主要包括各部分电路介绍,软件框架将给出粉尘监测器与蓝牙接入设备的通信流程及相关程序。     

基于蓝牙技术的MPEG-4视频流传输性能分析

提出了一种基于蓝牙技术和MPEG-4视频标准的短距离无线视频传输方案(MPEG4-BT),应用于室内数字视频信号的无线传输,同时分析了MPEG-4比特流在蓝牙HCI层的传输特性,以及同一环境多个蓝牙piconet进行视频通信的吞吐量.该方案可以大大拓宽蓝牙的应用范围,为进一步利用蓝牙实现无线视频通信提供参考.     

基于蓝牙4.0的设备通信方案设计与实现

对基于蓝牙4.0的设备通信问题进行了深入研究,提出了基于CC2450F128芯片的蓝牙通信解决方案。设计了通信方案的总体框架,完成了CC2450F128的通信电路设计和通信协议的扩展。该方案能够提供较稳定的信号强度测量,可以高效的发现蓝牙设备,有效地解决了多个蓝牙设备同时连接通信的问题,并且改善了设备的断开连接误报率。     

基于蓝牙的数据互联传输系统设计

在基于蓝牙协议体系及蓝牙通用应用框架的基础上,研究了嵌入式蓝牙数据的传输技术,设计了蓝牙数据传输系统。系统采用流行的ARM处理器,并选用了CSR公司的CSR8510蓝牙芯片作为蓝牙通信的核心,最后设计了蓝牙数据传输软件。总体来说,在此所设计的蓝牙数据传输系统具有价格低,性能强,通用性好以及扩展能力强等优点。     

多层介质多导体传输线的小波矩量法分析

全电荷格林函数法是解决分层介质的多导体传榆线的参数提取的一个通用有效的方法，但是用矩量法处理时需将导体表面和介质分界面一起剖分，系数矩阵的阶数较大，计算效率降低。详细分析了多层介质多导体传榆线，并在矩量法处理时引入小波变换，使原稠密系数矩阵变换为稀疏矩阵。从而提高了求解速度。     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Nanoimprint Lithography -A Next Generation High Volume Lithography Technique

IntroductionNanoimprint Lithography is a well-acknowl-edged low cost, high resolution, large area pattern-ing process. It includes the most promising methods,high-pressure hot embossing lithography (HEL) [2],UV-cured imprinting (UV-NIL) [3] and micro contactprinting (m-CP, MCP) [4]. Curing of the imprintedstructures is either done by subsequent UV-lightexposure in the case of UV-NIL or by cooling downbelow the glass transition temperature of the ther-moplastic material in case of HEL…     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

Influence of PVK ： NPB hole transporting layer on the characteristics of organic light-emitting devices

A doping system consisting of NPB and PVK is employed as a composite hole transporting layer （CHTL）. By adjusting the component ratio of the doping system, a series of devices with different concentration proportion of PVK ： NPB are constracted. The result shows that doping concentration of NPB enhances the competence of hole transporting ability, and modifies the recombination region of charge as well as affects the surface morphology of doped film. Optimum device with a maximum brightness of 7852 cd/m^2 and a power efficiency of 1.75 lm/W has been obtained by choosing a concentration proportion of PVK ： NPB at 1：3.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.     

Analysis of error performance on Turbo coded FDPIM

Due to variable symbol length of digital pulse interval modulation（DPIM）, it is difficult to analyze the error performances of Turbo coded DPIM. To solve this problem, a fixed-length digital pulse interval modulation（FDPIM） method is provided. The FDPIM modulation structure is introduced. The packet error rates of uncoded FDPIM are analyzed and compared with that of DPIM. Bit error rates of Turbo coded FDPIM are simulated based on three kinds of analytical models under weak turbulence channel. The results show that packet error rate of uncoded FDPIM is inferior to that of uncoded DPIM. However, FDPIM is easy to be implemented and easy to be combined, with Turbo code for soft-decision because of its fixed length. Besides, the introduction of Turbo code in this modulation can decrease the average power about 10 dBm, which means that it can improve the error performance of the system effectively.     

A method for calculating the center position of collimated light

It is a key problem to accurately calculate beam spots＇ center of measuring the warp by using a collimated laser. A new method, named double geometrical center method （DGCM）, is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device （CCD） is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What＇s more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.     

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.