一种具有新型增益控制技术的CMOS宽带可变增益LNA

高速超宽带无线通信的多标准融合是未来射频器件的发展趋势,该文提出一种基于CMOS工艺、具有新型增益控制技术的宽带低噪声放大器(LNA),采用并联电阻反馈实现宽带输入匹配,并引入噪声消除技术来减小噪声以提高低噪声性能;输出带有新型6位数字可编程增益控制电路以实现可变增益。采用中芯国际0.13m RF CMOS工艺流片,芯片面积为0.76 mm2。测试结果表明LNA工作频段为1.1-1.8 GHz,最大增益为21.8 dB、最小增益8.2 dB,共7种增益模式。最小噪声系数为2.7 dB,典型的IIP3为-7 dBm。     

一种5~6 GHz宽带全集成CMOS低噪声放大器

采用55 nm标准CMOS工艺,设计并流片实现了一种应用于Wi-Fi 6(5 GHz)频段的宽带全集成CMOS低噪声放大器(LNA)芯片,包括源极退化共源共栅放大器、负载Balun及增益切换单元。在该设计中,所有电感均为片上实现;采用Balun负载,实现信号的单端转差分输出;具备高低增益模式,以满足输入信号动态范围要求。测试结果表明,在高增益模式下该放大器的最大电压增益为20.2 dB,最小噪声系数为2.2 dB;在低增益模式下该放大器的最大电压增益为15 dB,最大输入1 dB压缩点为-3.2 dBm。芯片核心面积为0.28 mm²,静态功耗为10.2 mW。     

一种电流舵结构大范围连续可变增益LNA

设计了一款应用于4G(TD-LTE)的可变增益低噪声放大器(VGLNA)。输入级采用共栅极跨导增强结构,实现了电路的输入阻抗匹配,并且加入共栅极噪声抵消电路,降低了电路的噪声系数;第2级采用改进型电流舵结构,实现了电路的增益大范围连续可变;输出级采用源跟随器,实现了良好的输出阻抗匹配。基于TSMC 0.18 μm CMOS工艺,利用安捷伦射频集成电路设计工具ADS2009进行仿真验证。结果表明:在1.88~2.65 GHz频段内,该LNA在2.7~39.3 dB增益范围内连续可变,且输入端口反射系数S₁₁小于－10 dB,输出端口反射系数S₂₂小于－20 dB,最小噪声系数NF为2.6 dB,最大3阶交调点IIP3达到2.7 dBm。     

一种新型的5GHz自适应偏置及可变增益低噪声放大器

该文提出了一种新型的自适应偏置及可变增益低噪声放大器(LNA),利用电荷泵(亦称电压倍增器)将LNA输出信号转换成与LNA射频输入信号功率成比例变化的直流信号,以此信号同时反馈控制LNA的偏置和增益,来实现自适应偏置以及可变增益低噪声放大器, 从而极大地改善了LNA的输入线性范围。鉴于5GHz频率下,Bipolar相对于CMOS更好的频率特性和低噪声特性,该项研究采用了BiCMOS工艺,实现了低于3.0dB的噪声系数(高增益状态下)和大约13dBm的输入三阶交调点IIP3的控制范围以及大于15dB的增益控制范围。     

一个950MHz CMOS低噪声放大器的设计

介绍了一个采用0.18μm 1.8V RF CMOS工艺,适合GSM接收器,中心频率为950MHz的低噪声放大器(LNA)的设计过程,并给出了spectreRF的模拟结果.在935～960MHz频带内,LNA功率增益大于16dB,阻抗匹配系数S11小于-18dB,噪声系数(NF)小于2.7dB,IIP3为-3.06dBm,ldB压缩点为-10.955dBm,功耗小于20mW.     

1GHz 0.5μm CMOS低噪声放大器的设计

从低噪声放大器(LNA)的设计原理出发,提出并设计了一种工作于1GHz的实用LNA.电路采用共源-共栅的单端结构,用HSPICE软件对电路进行分析和优化.模拟过程中选用的器件采用TSMC 0.5μm CMOS工艺实现.模拟结果表明所设计的LNA功耗小于15mW,增益大于10dB,噪声系数为1.87dB,IIP3大于10dBm,输入反射小于-50dB.可用于1GHz频段无线接收机的前端.     

CMOS宽带线性可变增益低噪声放大器设计

文章设计了一种48MHz~860MHz宽带线性可变增益低噪声放大器,该放大器采用信号相加式结构电路、控制信号转换电路和电压并联负反馈技术实现。详细分析了线性增益控制、输入宽带匹配和噪声优化方法。采用TSMC0.18μm RF CMOS工艺对电路进行设计,仿真结果表明,对数增益线性变化范围为-5dB~18dB,最小噪声系数为2.9dB,S11和S22小于-10dB,输入1dB压缩点大于-14.5dBm,在1.8V电源电压下,功耗为45mW。     

基于有源电感的全集成超宽带低噪声放大器

利用有源电感来实现超宽带低噪声放大器(UWB LNA),不但可以减小芯片面积、改善增益平坦度,而且可通过外部调节偏置电压来调谐有源电感的电感值,进而调整设计中没有考虑到的由工艺变化及封装寄生带来的增益退化.采用TSMC 0.35 μm SiGe BiCMOS工艺,利用Cadence设计工具完成了放大器电路及版图的设计.在3.1～10.6 GHz工作频率范围内,通过外部调节电压来调谐有源电感,可使LNA的增益S21在16～19 dB范围内变化,输入输出回波损耗S11,S22均小于-10 dB,噪声为2.4～3.7 dB,输入3阶截点IIP3为-4 dBm.整个电路芯片面积仅为0.11 mm2.     

1.5-6GHz增益和噪声系数稳定的两级超宽带CMOS低噪声放大器设计与性能模拟

 针对UWB应用设计实现了一个1.5-6GHz的两级CMOS低噪声放大器(LNA). 通过引入共栅(CG)和共源(CS)结构以获得宽范围内的输入匹配,采用电流镜和峰化电感进行电流复用,所提出的LNA实现了非常平坦化的功率增益和噪声系数(NF). 经标准0.18μm CMOS工艺实现后,版图后模拟结果表明在1.5-5GHz频率范围内功率增益(S21)为11.45±0.05dB,在2-6GHz频率范围内噪声系数(NF)为5.15±0.05dB,输入损耗(S11)小于-18dB. 在5GHz时,模拟得到的三阶交调点(IIP3)为-7dBm,1dB压缩点为-5dBm.在1.8V电源电压下,LNA消耗6mA的电流,版图实现面积仅为0.62mm^2.     

应用于5GHz频段带ESD保护的可变增益低噪声放大器

本文给出了应用于5GHz频段的可变增益低噪声放大器。详细分析了输入寄生电容对源极电感负反馈低噪声放大器的影响,给出了一种新的ESD和LNA联合设计的方法,另外,通过在第二级中加入一个简单的反馈回路实现了增益的可变。测试结果表明： 可变增益低噪声放大器增益变化范围达25dB (-3.3dB～21.7dB),最大增益时噪声系数为2.8dB,最小增益时三阶截点为1dBm,在1.8V电源电压下功耗为9.9mW。     

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.