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1.
M otorola公司的 MRFIC1859是一款双频单电源(3.6V)RF集成功率放大器,设计用于GSM900/DCS1800手持无线装置。改变匹配电路,它也可以用于3频GSM900/DCS1800/PCS1900装置。3.6V下的典型特性是:GSM:Pout=35.8dBm, PAE=53%;DCS: Pout=34dBm, PAE=43%。它具有一个宽频带(900-1800MHz)内部负电压产生器,此负电压产生器是基于输入载波经2级缓冲器放大后的RF整流(见图1)。这种方法消除了采用dc/dc…  相似文献   

2.
张浩 《电信技术》2000,(4):33-34
N ISDN给用户提供两种速率接口 :基本速率接口(BRA)和基群码率接入(PRA)。BRA由2个B通道(64kb/s)和1个D通道(16kb/s)组成 ;PRA由30个B通道(64kb/s)和1个D通道(64kb/s)组成。本文将介绍PRA及其在S-12J上的实现。1PRA简介通常PRA通过NT2 ISDNPABX(ISPBX)给用户提供服务 ,ISPBX也是一个PABX ,大部分ISPBX的数据存放在PARM(SACEPABX)中 ,能够通过2Mb/s的PRA接口实现点到点的连接。2Mb/sPCM由30…  相似文献   

3.
介绍了一种新型的高性能雷达频率综合器的制作方法,即采用声表面波技术制作高性能的雷达频综器。采用这种方法成功地制造了L波段、S波段、C波段超低相位噪声超高速频率综合器。该类频综输出信号具有极低相位噪声(1.6GHz处:单边带相位噪声Lm(1kHz)=-127dBc/Hz;3.4GHz处:Lm(1kHz=-122dBc/Hz;6.8GHz处:Lm(1kHz)=-116dBc(Hz)、极短的频率切换时间(约160ns)、低杂波电平(L波段为-70dB;S波段为-65dB;C波段为-60dB)、较多频点(51点)等多项优异性能。同时,该频综通过了各项环境试验的考核,且长期工作性能稳定。  相似文献   

4.
在793.2km G.652光纤上的10 Gbit/s传输实验   总被引:1,自引:0,他引:1  
介绍了国内首次在793.2kmG.652光纤上进行的10Gbit/s系统传输实验,本次实验使用武汉邮电科学研究院研制的10Gbit/sSDH设备,以及10只EDFA与补偿量为720km的色散补偿光纤,实验结果表明:在误码率BER=10^-12接收灵敏度可达到-18.8dBm,传输实验的通道代价为0.4dB。  相似文献   

5.
文章介绍了一种双频切换,低相噪介质稳频振荡器(DRO)的设计方法。运用微波CAD设计的C波段DRO,其相位噪声可达到-72~-75dBc/1Hz/1kHz,最佳为-80dBc/1Hz/1kHz;输出功率大于20mW;推频系数小于100kHz/V;可在-20℃~+55℃工作。  相似文献   

6.
描述了2-4GHz、8-12GHz的SPDT和8-12GHz的SP3T大功率PIN开关的设计方法、实现过程和测试结果。其连续波功率最大可承受80W,插入损耗小于1.8dB,,隔离度大于25dB,驻波比小于1.8,开关时间小于1us具有功率容量大,工作频带宽、可靠性高,成本低,调试简单等特点。  相似文献   

7.
李同宁  罗毅 《光通信研究》1999,(3):42-46,54
本文报道了采用全MOCVD生长的1.55μm单片集成DFB-LD/EA组件的制作和在DWDM系统上的传输测试结果,该发射模块在2.5Gbit/s DWDM系统上进行传输试验,传输240km后无误码,其通道代价≤1dB,BER=10^-12。  相似文献   

8.
本文用束传播方法(BPM)设计了具有弯曲波导吸收区结构1.3μmInGaAsP/InP超辐射发光二极管(SLD),分析了不同吸收区长度La和弯曲的曲率半径R对SLD特性的影响,给出了直观的结果,并进行了优化设计。在假定吸收区后端面反射率为1,和忽略吸收区内的吸收损耗的条件下,取d=0.2μm,w=2μm,Lp=400μm,La=200μm,R=500μm,I=200mA,经吸收区反射耦合回有源区内的光与有源区前端面入射光的强度比率仅为9.5×10-3。  相似文献   

9.
报道Ka频段GaAs单片平衡混频器的设计和研究结果。用自行开发的“TUMMIXER”软件进行电路设计,工艺以半绝缘GaAs为衬底,采用NbMo/GaAs接触形成肖特基势垒二极管,以SiO2和聚酰亚胺双介质为保护膜,增强了工艺的成功率。研制成功的芯片尺寸为:2mm×3mm×0.2mm,在f=31~36GHZ范围内NFSSB≤10dB,最佳点f=32.2GHzNF.SSB=8.7dB[fIF=1.2GHz]。  相似文献   

10.
本文介绍I/Q通道误差自动校正的实现方法。校正网络由组合逻辑组成,可以校正同相支路和正交支路的幅相误差和直流偏移。校正系数由DSP根据相参测试信号算出。当幅度误差为0.1dB,相位误差为5°时,产生的相对镜像电平为-27dB。经过误差自动校正后,相对镜像电平下降到-52dB。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
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.  相似文献   

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