A passive UHF RFID tag with a dynamic-Vth-cancellation rectifier

This paper presents a passive UHF RFID tag with a dynamic-Vth-cancellation(DVC) rectifier. In the rectifier, the threshold voltages of MOSFETs are cancelled by applying gate bias voltages, which are dynamically changed according to the states of the MOSFETs. The DVC rectifier enables both low ON-resistance and small reverse leakage of the MOSFETs, resulting in high power conversion efficiency(PCE). An area-efficient demodulator with a novel average detector is also designed, which takes advantage of the rectifier’s first stage as the envelope detector. The whole tag chip is implemented in a 0.18 μm CMOS process with a die size of 880×950 μm2. Measurement results show that the rectifier achieves a maximum PCE of 53.7% with 80 kΩ resistor load.     

空间光谱仪光栅柔性支撑设计与分析

针对目前空间遥感器主支撑结构设计中难以同时保证光学元件刚度大、尺寸热稳定性好的问题,提出了一种具有柔性环节的支撑结构,有效地解决了影响基于空间环境的一种光栅光谱仪成像质量的力、热两个关键环境约束之间的矛盾。根据光学设计指标要求确定了光栅基板的结构形式,通过理论计算对柔性支撑的尺寸参数进行了灵敏性分析,得到了各尺寸对转角刚度的影响权重。通过优化柔性支撑件尺寸参数使光栅组件性能达到最优,利用有限元分析（FEA）软件对光栅组件在力、热耦合作用下的面形精度和动态刚度进行了仿真分析。结果表明,光栅及其支撑结构设计合理,满足空间应用要求,为柔性支撑的深入研究和应用提供了参考。     

运营商大数据平台的敏感信息保护研究

探讨了运营商大数据平台的敏感信息范围,给出了敏感信息保护的方法步骤,总结了该研究领域内的关键技术及每类技术的主流技术方法,并针对实际的运营商大数据平台的分层架构,设计了不同敏感信息保护技术的技术实现方案.     

宽温环境下磁光盘写入光功率的优化

利用有限单元法研究了环境温度、写入光功率、磁光盘膜面温度分布三者间的关系，在此基础上导出了宽温环境下的最优写入条件，该条件为优化宽温磁光盘读出性能提供了依据。     

室温脉冲螺旋Wiggler磁体和大电流脉冲电源的研究

本文研究了适用于自由电子激光的室温脉冲螺旋Ｗｉｇｇｌｅｒ磁体，对其设计构思、磁场特性和设计参数进行了分析和计算．作者在文中还研究并设计了螺旋Ｗｉｇｇｌｅｒ磁体的大电流宽脉冲供电电源；分析了脉冲电流的时间特性对产生自由电子激光的影响程度．     

Preparation of Uniform,Water‐Soluble,and Multifunctional Nanocomposites with Tunable Sizes

Novel, thiol‐functionalized, and superparamagnetic, silica composite nanospheres (SH‐SSCNs) with diameters smaller than 100 nm are successfully fabricated through the self‐assembly of Fe₃O₄ nanoparticles and polystyrene₁₀₀‐block‐poly(acrylic acid)₁₆ and a subsequent sol‐gel process. The size and magnetic properties of the SH‐SSCNs can be easily tuned by simply varying the initial concentrations of the magnetite nanoparticles in the oil phase. By incorporating fluorescent dye molecules into the silica network, the composite nanospheres can be further fluorescent‐functionalized. The toxicity of the SH‐SSCNs is evaluated by choosing three typical cell lines (HUVEC, RAW264.7, and A549) as model cells, and no toxic effects are observed. It is also demonstrated that SH‐SSCNs can be used as a new class of magnetic resonance imaging (MRI) probes, having a remarkably high spin–spin (T₂) relaxivity (r₂* = 176.1 mM ^?1 S^?1). The combination of the sub‐100‐nm particle size, monodispersity in aqueous solution, superparamagnetism, and fluorescent properties of the SH‐SSCNs, as well as the non‐cytotoxicity in vitro, provides a novel and potential candidate for an earlier MRI diagnostic method of cancer.     

Light extraction efficiency enhancement of GaN-based light emitting diodes by a ZnO current spreading layer

preading layers are analyzed.     

水声通信网络问题研究

本文介绍了水声通信网络的特点与拓扑,深入研究了水声通信网络各层的功能,分析了各层所遇到的问题并提出了相应的解决对策.     

COMPLEX RAY ANALYSIS OF SCATTERING FROM RAM COATED TARGETS

With the extension of complex ray theory(CRT)from lossless media into lossy ones,the complex ray analysis in lossy media can be constructed and effectively used in the problemsof scattering analysis of objects coated with radar absorbing materials(RAM).This method hassome advantages,such as simple calculation procedure,clear physical meaning,wide applicationarea etc.As an example,the radar cross-section(RCS)of conducting flat plates coated withRAM is analyzed.The results show that the theoretical predictions agree very well with theexperimental results.     

低RCS选频滤波反射面天线技术

利用具有带阻选频特性的周期结构表面替代普通金属反射面构成的滤波反射面天线是一项克服天线散射的有效技术途径.本文给出了滤波反射面天线辐射特性和RCS的实测结果;分析讨论了此种天线的性能和可行性.