基于MSP430F2272单片机的多路光功率计的设计

介绍了一种基于MSP430F2272单片机的多路光功率计的设计原理和实现方法。MSP430F2272单片机具有多路模拟输入复用端口的片上集成10位模数转换器,可在低功耗条件下实现测量多路光信号功率的功能。整个设计简单实用,易于实现。     

基于ATmega16的数字光功率计设计

介绍了基于ATmega16的数字光功率计系统设计方案。利用智能单片机ATmega16对系统进行控制,通过AD7705和CD4051相结合的方式对不同量程的信号进行采集,提高了系统精度和测量范围。显示部分采用1602液晶实现光功率显示功能。该光功率计的制作成本低,集成度高,降低了系统复杂度,实现了高精度的光功率测量,作为教学辅助测量仪器,效果良好。     

基于ATmega 128的高速高精度光功率计的设计

介绍了一套最新研制的高速高精度光功率计的设计方案。该光功率计采用高性能单片机ATmega l28对系统进行控制,以目前业界速度最快16位低功耗、高性能的AD9467为模/数转换器对不同量程的信号进行采集,提高了数据的精度性。通过USB2.0的高速通信能力,充分发挥了ATmega 128的高速采集处理能力。     

室内型上行光接收机GSD8100Q

GSD8 10 0Q为高增益室内型下行光接收机,具有极高的性价比,主要应用于有线电视二级光网接收中继站等,该产品主要特点有:860M设计,频率范围:47～860MHz。高精度八位LED接收光功率显示。调试无须光功率计。整机采用特殊的低功耗设计,大大降低了本机的温升,提高了使用寿命和可靠性室内型上行光接收机GSD8100Q$成都康特公司     

NI拓宽智能相机系列产品选择

美国理想工业公司（IDEAL INDUSTRIES,INC．,以下简称美国理想）近日推出了FiberMASTER光功率计,可测量多波长绝对光功率值与衰减值。FiberMASTER光功率计可测量多模和单模光纤,测量的波长包括850nm、1310nm、1490nm及1550nm是认证和排除各种类型光缆故障的专业工具。用户可利用其dB校准功能,对光源设置参考电平,并直接读取光链路衰减值,无需人工计算。     

GJ-2490双通道智能化光功率计

GJ-2490是具有两个通道的光功率计,可用于光纤通信、测量系统的高精度、高稳定测量。它的高灵敏性使它有能力测量-90dBm的0.85μm和1.3μm波长的光功率。可测光功率的波长范围为0.4μm到1.7μm。基本测量系统由主机和两个探头组成。根据不同的光功率电平和波长范围可从四个探头中选择任意两个使用。该仪器具有两个独立的可同时显示的通道,两个通道间可进行数据处理,并具有数据存贮、波长校正、平均值显示、自动调零等功能。该仪器使用Z80-CPU作为核心控制元件,实现了光功率计的智能化。测量量程的扩展和切换取决于放大器放大和衰减倍数的不同组合。     

微功耗光功率计的研制与线性处理

手持光功率计作为光纤通信测试仪表中最为普及和用量最大的测试仪表,在光纤施工被广泛使用.由于经常在户外使用,所以要求仪表具有功耗低、测量精确、便于携带等特点.目前,国内同类仪表与国外相比,存在相当大的差距.微功耗手持光功率计采用低功耗器件进行设计,并对软件进行适当的算法处理.实测数据分析表明:该光功率计整机功耗小于30mW,不确定度为0.1dBm,达到国外仪表同等技术指标.可满足高校实验室的教学和光通信施工部门的施工检测与维护需求,具有广阔的市场前景.     

便携式可通信光纤测试仪的研究

介绍了一种兼具光功率测量和数字信号、音频信号传输性能的便携式可通信光纤测试仪,阐述了其设计原理和实现方法.该仪器具有光话机与光功率计一体化功能,可对光功率值范围为0～-60dBm、音频信号传输范围为0～-50dBm、数字信号传输范围为0～-45dBm的信号进行测量,测试结果具有很高的精度.     

智能化光功率计AY-2494

本文着重介绍智能化光功率计Ay-2494的自校,dB功能和校准系数的设置以及显示。应用MCS-48系列的8035单片微机使得智能化光功率计Ay-2494具有多种功能和许多独到之处。     

一种高灵敏度近红外光纤光功率计的设计

基于InGaAs光电二极管设计了一种高灵敏度的近红外光纤光功率计。该光功率计的前置放大电路采用多档放大量程设计,外加屏蔽盒,提高了测量动态范围。采用差分放大器、差分A/D转换芯片抑制系统的共模噪声。通过温度传感器测量了环境温度,使用D/A转换芯片对前置放大电路进行动态调零,从而抑制了系统的杂散光噪声、光电探测器的暗电流噪声以及光电探测器的温度漂移。测试表明,该光功率计在光纤通信光波段的光功率测量灵敏度达到-90 dBm,测量动态范围、系统信噪比、线性度等指标均显著提高。     

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.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

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