1.8 V千兆以太网接收器模拟前端预均衡电路

介绍了一种用于1.8 V电源电压下的千兆以太网接收器的模拟前端预均衡电路。电路分为三个部分:预处理电路、基带漂移补偿电路和可变增益放大电路,主要实现回波消除、基带漂移补偿和电路增益自动控制等功能。为了与百兆模式兼容,提出了一种预处理电路。仿真结果表明,该电路可以很好地实现回波消除的功能,能够对由于基带漂移引起的信号失真给以补偿,可以提供16级不同的增益,并进行频率补偿。电路采用0.18μm标准CMOS工艺实现。     

一种用于以太网收发器的基带漂移消除器的设计

根据0.13μm/2.5 V 1P8M CMOS工艺提出了一种用于以太网收发器的基带漂移消除器的结构设计,该结构由电荷泵电路、OTA、电流补偿电路3部分组成。基带漂移消除器补偿了由于变压器的高通特性引起的基带漂移现象。仿真结果表明所设计的电路达到了以太网收发器的系统要求,很好地实现了对基带漂移的补偿。     

一种具有温度补偿的宽带CMOS可变增益放大器

设计实现了一个具有温度补偿的宽带CMOS可变增益放大器,该可变增益放大器的核心电路由三级基于改进型Cherry-Hooper结构的可变增益单元级联而成,并通过一种温度系数增强的且可编程的偏置电路和增益控制电路对可变增益放大器的增益进行温度补偿。采用中芯国际0.13μm CMOS工艺流片,测试结果表明可变增益放大器的可变增益范围为-13～27dB,经过温度补偿后,在相同增益控制电压下其增益在0～75°C温度范围内的变化范围不超过3dB。可变增益放大器的3dB带宽为0.8～3GHz,输入1dB压缩点为-50～-21dBm,在1.2V电压下,功耗为21.6mW。     

一种带有外部噪声识别功能的AGC电路的设计

基于红外遥控接收芯片中自动增益控制电路的功能需求及其应用环境,设计了一种能够有效抑制外部环境光干扰、线性度高的自动增益控制电路。该电路在传统自动增益控制电路的设计理念基础上引入外部噪声识别功能,设计的核心子电路包括具有线性增益特性的可变增益放大器、比较器以及利用空闲时间识别外部噪声的信号检测与增益控制电路。电路基于0.25μm标准CMOS工艺设计,使用Hspice软件进行仿真验证。仿真结果表明:电源电压为3～5 V,温度为0～85℃时,可变增益放大器的可控增益范围至少可达-69.5～27.6 dB,且至少具有42 dB的线性增益控制范围。     

CMOS宽带可变增益放大器

设计了一种CMOS宽带、低功耗可变增益放大器.在分析使用源极退化电阻的共源放大器高频特性基础上,通过加入频率补偿电容改变放大器的零极点分布,在不增加功耗的情况下扩展了带宽.分析了放大器在低增益下出现的增益尖峰现象并加以解决.使用跨导增强电路提高了放大器的线性度.两级可变增益放大器使用TSMC0.25μm CMOS工艺.仿真结果表明,放大器在3.3V电压下核心电路功耗为3.15mW,增益范围0～40dB;在负载为5pF电容时3dB带宽大于340MHz,输出三阶交调点高于3.5dBm.     

CMOS宽带可变增益放大器

设计了一种CMOS宽带、低功耗可变增益放大器.在分析使用源极退化电阻的共源放大器高频特性基础上,通过加入频率补偿电容改变放大器的零极点分布,在不增加功耗的情况下扩展了带宽.分析了放大器在低增益下出现的增益尖峰现象并加以解决.使用跨导增强电路提高了放大器的线性度.两级可变增益放大器使用TSMC0.25μm CMOS工艺.仿真结果表明,放大器在3.3V电压下核心电路功耗为3.15mW,增益范围0～40dB;在负载为5pF电容时3dB带宽大于340MHz,输出三阶交调点高于3.5dBm.     

GNSS接收机带有滤波功能可变增益放大器的设计

传统GNSS前端接收机系统中,可变增益放大器（VGA）不具备滤波功能,大多数选用片外滤波,这样系统增益和集成度降低,而系统集成的波器选频性能有限。为此,设计一种具有滤波功能的可变增益放大器,采用0．5μmSiGe HBT工艺,可控增益单元与Gm-C滤波单元集成一体,并运用4晶体管回转器结构实现滤波。电路驱动电压为3.3V,电流为11．7mA。线性增益控制范围为-26～62dB,且电压控制范围为0．1．8V,最小增益下输入1dB压缩点为-4dBm。可变增益放大器电路不仅具备大的增益控制范围,而且中频46MHz处滤波性能良好,提高芯片的集成度．降低系统功耗。     

增益可控低噪声前置放大器设计

设计一种具有温度补偿、增益可控的低噪声前置放大器。该放大器采用级联放大,每一级通过继电器改变信号通路,从而达到控制增益的目的。在放大器的设计中采用噪声抑制和温度补偿技术,并对原电路使用闭环控制进行优化,既实现了增益可调,增益控制范围为10~60 dB,又保证了良好的增益平坦度和优秀的噪声抑制能力。通过仿真和实际电路波形测试,表明该放大器仅有9μV/℃温度漂移和10 nV/Hz~(1/2)等效输入噪声电压,总谐波失真小于1.2%,能放大μV级DC~50 MHz带宽信号。     

CMOS可变增益放大器指数变化控制电路设计

文章设计了一种新颖的CMOS可变增益放大器增益指数变化控制电路。在理论分析一模拟乘法器的基础上,采用数学逼近的原理,提出实现了一种伪指数增益控制电路,得到很好的dB-线性特性。该电路工作电压3V,采用CSMC0．6μm工艺设计实现约30dB范围的增益控制。     

1.8～2.7GHz可调谐八波段时分LTE多模接收机前端的分析与设计

摘要：本文阐述了支持八波段可调谐时分LTE多模接收机前端的分析与设计,覆盖1.8～2.7GHz频率范围并支持5/10/15/20MHz三种带宽和QPSK/16QAM/64QAM 三种调制方式。零中频可调谐接收机前端的设计包括了可调谐窄带可变增益低噪声放大器,电流型下变频混频器和二阶低通输出跨阻放大器,可变增益预放大器,可调谐四阶切比雪夫低通信道选择滤波器和截止频率矫正电路,中频可变增益放大器。 窄带低噪声放大器可以在调谐范围内自由调节中心频率,从而替代了传统多模接收机中的低噪声放大器阵列,节省了芯片面积。模拟基带部分也可以通过数字接口调节增益和信道选择带宽。芯片在SMIC 0.13μm 1P8M CMOS上实现,测试结果显示双边带噪声系数达到4.6dB, 带外IIP3达到-14.5dBm,30～94dB增益范围。1.2V电源电压下芯片消耗功耗为54mA。     

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.     

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.     

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