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对ITU-R 837-2模式计算中国雨强分布的应用分析

论述了国际电联ITU-R 837-2模式计算雨强值的方法,在地理信息系统。(GIS)和数据库技术的支持下,对该方法进行了应用分析研究。首先对全国2937个县市进行单站点雨强计算;然后选择73°E～135°E,15°N～55°N范围,按几何分辨率即象元大小为经度3’×纬度3’制成格网,并逐栅格点计算雨强,以中国边境为界提取雨强值,并绘制等值线及分布图。经与典型站点分钟雨强值及国军标雨强分布图进行对照分析,指出了该方法在反演中国雨强分布中的可行性与局限性,并提出进一步完善该模型的建议。     

人工雾的激光退偏振特性

分别测量了入射光偏振方向垂直散射面和平行散射面情况下,散射角θ分别为30°和90°时,不同人工雾的浓度的散射光强度。实验表明:θ=30°时,薄雾状态,散射光强随雾的浓度的增加而增大,当雾浓度达一定程度后,散射光随浓度的增加而减小;θ=90°时,随着雾的浓度的增加,散射光强逐渐增大,散射光强在浓度较大时呈现下降趋势。以Mie散射理论分析了偏振光在人工雾中的散射特性,并由散射角为90°时的退偏振度随雾的浓度的变化,讨论了雾粒子的结构及性质。     

二次编码的多路无线遥控器设计

以AT89C51为主控芯片,数据经二次编解码以无线载波的方式进行传输,提高了遥控的准确性。可在12米以外准确遥控14路电器的工作状态。本系统具有使用方便、设置灵活、功耗低、安全性强、易扩展等优点,并可设置可燃气体报警功能。     

小型化前倾毫米波双狭缝天线的设计与制作

常规侧向探测天线主波束垂直于天线辐射面,会导致飞行探测漏报率高,因此有必要研究具有前倾探测功能的天线,以提高探测准确率。基于HFSS软件,设计了狭缝天线结构。设计的输入参数如下：频段为36.85~37.15 GHz,收发隔离度优于50 dB,前倾角为20°~24°,旁瓣抑制度要求大于-10 dB,天线长度小于85 mm,方位角大于80°,俯仰角小于11°,增益大于11 dB。测试结果表明,天线增益为12 dB,在36.85~37.15 GHz条件下,方位角位于116°~134°之间,俯仰角位于8°~9°之间,前倾角在22°~24°之间,旁瓣抑制度位于-11.45~-14.60 dB之间,且波束方向可控。在36.5~37.5 GHz频率范围内,驻波比保持在1.413以下,收发隔离度保持在-51.132以下,天线总长度为83 mm。该天线的测试结果与设计一致,能满足设计要求,为无人机侧向探测器提供天线技术支撑。     

采用SGS—M494遥控芯片的多路开关量设计

采用ＳＧＳ－Ｍ４９４遥控芯片的多路开关量设计上海工业大学席科文，范天翔Ｍ４９４遥控系统是ＴＨＯＭＳＯＮ公司为遥控彩电开发的专用芯片，它具有四路模拟量控制，最大ｈｏ个频道号数码泰示功能。它的成本低，功能强，曾在遥控彩电领域发挥了很好的作用，但是随着遥控...     

抗干扰多通道红外遥控器电路设计

介绍了一种结构简单、使用方便的多通道红外遥控电路。该遥控电路主要由一对红外遥控编译码器 BA5101/BA5201、红外接收头和其它常用元器件组成,能够实现8个不同通道的遥控选择功能,电路具有抗干扰能力强、工作稳定等优点。     

红外遥控直流电动机控制器

红外线遥控装置具有体积小、功耗低、功能强、成本低等特点,是日前使用广泛的一种近距离无线通信和遥控方式。主要介绍了红外遥控器对直流电动机运行参数进行设定,包括直流电机启动、停止、正转、反转以及转速的设置,同时实时监控电动机的转速并显示,以红外线传输技术实现遥控功能。     

东亚中纬地区的电离层闪烁

本文分析了新乡（３５．３°Ｎ，１１３．９°Ｅ，ＥＴＳ—Ⅱ卫星３００ｋｍ对下点纬度３２．９°Ｎ）幅度闪烁资料，并综合Ｋｏｋｕｂｕｎｉｌ（３５．７°Ｎ，１３９．５°Ｅ，ＥＴＳ—Ⅱ卫星３００ｋｍ对下点纬度３３°Ｎ）、Ｋａｓｈｉｍａ（３５．９５°Ｎ，１４０．６７°Ｅ，ＥＴＳ—Ⅱ卫星３００ｋｍ对下点纬度３３．７°Ｎ）和Ｙａｍａｇｕｃｈｉ（３４．２°Ｎ，１３１．６°Ｅ，印度洋上空ＭＡＲＩＳＡＴ卫星３００ｋｍ对下点纬度３１．５°Ｎ）站结果，得到了如下东亚中纬地区电离层闪烁的特征：１．中纬区ＶＨＦ和Ｌ波段电离层闪烁基本上是夜间现象，但夏季正午可出现次极大值；２．闪烁出现率季节变化明显，无论是ＶＨＦ波段，还是Ｌ波段，其出现率均以夏季最强，秋季次之，冬季最弱；３．逐年变化显著，夏季夜间，平均闪烁出现率与年平均平滑太阳黑子数（ＡＡＳＳＮ）的负相关关系明显，其它时间二者无关；４．夜间强闪烁和秋季午夜前后的弱闪烁，其出现率随Ｋｐ指数增加而减小，其它时间，则与Ｋｐ指数变化无关；５．夏季夜间强闪烁的平均出现率可能有经度效应，即新乡站强闪烁的夏夜平均出现率高于Ｋｏｋｕｂｕｎｊｉ站。     

角度测量系统ERA 150/180

功能 这是一种具有大内径、高精度开放式旋转编码器。 特点 ·最小显示角度为1″或0.0001°。 ·对于ERA—180型,与玻形形成回路IBV组合在一起,角度显示为0.0005°,转速可达6000rpm。     

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.     

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.     

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.     

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.     

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     

JOURNAL OF ELECTRONICS(CHINA)

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NEXT GENERATION WIRELESS NETWORKS–ESPECIALLY THE USE OF MILLI-MICROWAVE BANDS

The global bandwidth shortage of wireless communications has motivated the exploration of the naillimeter wave （ram-wave） frequency spectrum for the next generation wireless communications. Recent advances in RF CMOS technology and high speed baseband signal processing technologies have enabled tile extensive research and development of turn-wave wireless communications. The multi gigabit per second data rate of ram-wave system will lead to applications in many important scenarios, such as WPAN, WLAN,back-haul for cellular system. And the frequency bands include 28 GHz, 38 GHz, 45GHz, 60GHz, E-BAND and even beyond 100 GHz. The propagation and the imitation of the RF circuits design in these frequency bands make the directional antennas be inevitable for mm-wave communications.