高增益自偏S波段MMIC低噪声放大器

报道了具有高增益自偏结构的低噪声S波段MMIC宽带低噪声高增益放大器.该放大器是采用国际先进的0.25μm PHEMT工艺技术加工而成.电路设计采用了两级级联负反馈结构,并采用电阻自偏压技术,单电源供电,使用方便,可靠性高,一致性好.MMIC芯片测试指标如下:在1.9～4.2GHz频率范围内,输入输出驻波小于2.0,线性功率增益达30dB,带内增益平坦度为±0.7dB,噪声系数小于2.7dB.芯片尺寸:1mm×2mm×0.1mm.这是国内报道的增益最高,芯片面积最小的S波段放大器.     

基于RC-CR多相网络的镜频抑制接收机MMIC

基于RC-CR多相网络技术研制了一款S波段镜频抑制接收机单片微波集成电路(MMIC),在MMIC芯片上集成S波段低噪声放大器(LNA)、差分IQ混频器、本振(LO)驱动放大器、RC-CR多相网络滤波器等电路单元,实现了S波段单片镜频抑制接收机,解决了镜频接收机小型化的问题.电路、电磁场软件仿真以及采用GaAs赝配高电子迁移率晶体管(PHEMT)工艺流片后的结果表明,在S波段实现了噪声系数小于1.8 dB,增益大于12 dB,中频(150±5) MHz带内镜频抑制大于35 dBc的技术指标.MMIC的芯片尺寸为4.8 mn×2.5 mm×0.07 mm.此镜频抑制接收机MMIC具有指标优异、体积小、集成度高的特点,可广泛用于各种需小型化的相控阵雷达和通信系统中.     

一款130～140GHz MMIC低噪声放大器

基于90 nm栅长的InP高电子迁移率晶体管(HEMT)工艺,研制了一款工作于130 ～140 GHz的MMIC低噪声放大器(LNA).该款放大器采用三级级联的双电源拓扑结构,第一级电路在确保较低的输入回波损耗的同时优化了放大器的噪声,后两级则采用最大增益的匹配方式,保证了放大器具有良好的增益平坦度和较小的输出回波损耗.在片测试结果表明,在栅、漏极偏置电压分别为-0.25 V和3V的工作条件下,该放大器在130～ 140 GHz工作频带内噪声系数小于6.5 dB,增益为18 dB±1.5 dB,输入电压驻波比小于2:1,输出电压驻波比小于3:1.芯片面积为1.70 mm×1.10 mm.该低噪声放大器有望应用于D波段的收发系统中.     

基于0.15 μm pHEMT的超宽带低噪声放大器

采用RC负反馈、源极电感负反馈等方法,设计并制作了一种基于MMIC技术的3~15 GHz超宽带低噪声放大器,在超宽带范围内实现了优良的回波损耗和平坦的高增益。采用0.15 μm GaAs pHEMT工艺进行设计,该放大器的芯片尺寸为2 mm×1 mm,直流功耗为200 mW。在片测试结果表明,带内增益高达28 dB,4~12 GHz带宽范围内的噪声系数低于2 dB,输入/输出回波损耗大于15 dB,测试结果与仿真结果十分吻合。该低噪声放大器可应用于S,C,X,Ku波段外差接收机以及毫米波、亚毫米波接收机的中频模块。     

基于QFN封装的X波段GaAs T/R套片设计

基于陶瓷方形扁平无引脚(QFN)封装研制出4款X波段GaAs微波单片集成电路(MMIC),包括GaAs幅相控制多功能芯片(MFC)、功率放大器、低噪声放大器、开关限幅多功能芯片.利用QFN技术将这套芯片封装在一起,组成2 GHz带宽的QFN封装收/发(T/R)组件,输出功率大于1W,封装尺寸为9 mm×9 mm×1 mm.通过提高GaAsMMIC的集成度、放大器单边加电、内部端口匹配,创新性地实现了微波T/R组件的小型化.这几款芯片中最复杂的X波段幅相控制多功能芯片集成了T/R开关、六位数字移相器、五位数字衰减器、增益放大器及串转并驱动器.在工作频段内,收发状态下,增益大于5 dB,1 dB压缩输出功率(P-1)大于7 dBm,移相均方根(RMS)误差小于2.5.,衰减均方根误差小于0.3 dB,回波损耗小于-12 dB,裸片尺寸为4.5 mm×3.0 mm×0.07 mm.     

2～4GHz MMIC低噪声放大器

采用中国电子科技集团公司第十三研究所的GaAs PHEMT低噪声工艺,设计了一款2~4 GHz微波单片集成电路低噪声放大器(MMIC LNA)。该低噪声放大器采用两级级联的电路结构,第一级折中考虑了低噪声放大器的最佳噪声和最大增益,采用源极串联负反馈和输入匹配电路,实现噪声匹配和输入匹配。第二级采用串联、并联负反馈,提高电路的增益平坦度和稳定性。每一级采用自偏电路设计,实现单电源供电。MMIC芯片测试结果为:工作频率为2~4 GHz,噪声系数小于1.0 dB,增益大于27.5 dB,1 dB压缩点输出功率大于18 dBm,输入、输出回波损耗小于-10 dB,芯片面积为2.2 mm×1.2 mm。     

3.6~4.7GHz低噪声放大器

以一种经典的窄带低噪声放大器结构为基础,分析级联放大器的S参数,通过优化元件参数,获得了一种在3.6~4.7 GH z范围内具有低输入回波损耗、低噪声系数的放大器。采用标准的0.18μm RF CM O S工艺进行了设计和实现。芯片面积为0.6 mm×1.5 mm。测试结果表明:在3.6~4.7 GH z的范围内,该宽带低噪声放大器输入回波损耗小于-14 dB;噪声系数小于2.8 dB,增益大于10 dB。在1.8 V电源下功耗约为45 mW。     

应用于S波段的高线性低噪声放大器

采用E-mode 0.25um GaAs pHEMT工艺,2.0mm × 2.0mm 8-pin双侧引脚扁平封装,设计了一款应用于S波段的噪声系数低于0.5dB的低噪声放大器。通过采用共源共栅结构、有源偏置网络和多重反馈网络等技术改进了电路结构,该放大器具有低噪声,高增益,高线性等特点,是手持终端应用上理想的一款低噪声放大器。测试结果表明在2.3-2.7GHz内,增益大于18dB,输入回波损耗小于-10dB,输出回波损耗小于-16dB,输出三阶交调点大于36dB。     

基于前馈结构的宽带高线性低噪声放大器

设计制作了一款工作频率范围为0.5~30.0 MHz的短波宽带高线性低噪声放大器。采用前馈法线性化技术实现了放大器的高线性与低噪声,其中主放大器采用平衡式结构线性化技术大幅改善了放大器的二阶失真。由于主放大器和辅助放大器均采用Gain Block MMIC放大器,使得该放大器的物理尺寸为40 mm×25 mm,从而实现了小型化。测试结果表明,该放大器在0.5~30.0 MHz约5.9个倍频程的工作频率范围内实现了增益为12 dB,增益平坦度为0.35 dB,最大噪声系数为3.2 dB,输出三阶截点大于55 dBm,输出二阶截点大于100 dBm。     

宽带低噪声放大器单片微波集成电路

从行波放大器设计理论出发,研制了一款基于低噪声GaAs赝配高电子迁移率晶体管(PHEMT)工艺设计的2~20 GHz单片微波集成电路(MMIC)宽带低噪声放大器。该款放大器由九级电路构成。为了进一步提高放大器的增益,采用了一个共源场效应管和一个共栅场效应管级联的拓扑结构,每级放大器采用自偏压技术实现单电源供电。测试结果表明,本款低噪声放大器在外加+5 V工作电压下,能够在2~20 GHz频率内实现小信号增益大于16 dB,增益平坦度小于±0.5 dB,输出P-1 dB大于14 dBm,噪声系数典型值为2.5 dB,输入和输出回波损耗均小于-15 dB,工作电流仅为63 mA,低噪声放大器芯片面积为3.1 mm×1.3 mm。     

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