Wireless communications + + +

Commencing with the advancements that may be expected in 3G during the first decade of this century, we move on to anticipate subsequent developments based on what society might need and the technologies that may be required. The near demise of mobile satellite networks and removal of radio broadcasting from potential mobile radio bands will provide the necessary bandwidth for high capacity, high quality multimedia mobile services utilising a dense concentration of fibre networks coupled to radio cells of all sizes. The integration of many factors from high aerial platforms (haps) (that are located in the stratosphere and from terrestrial cells that can be adjusted in size and moved instantly to suit teletraffic changes) to picocells, body-LANs to the fixed network, software agents to soft telecommunications, will be discussed. Finally the possibility of our networks metamorphosing into a global brain, and how man-kind might adapt to this supra-intelligence will be addressed.     

BF_2~+,F~+ +B~+和Ar~++B~+注入硅快速退火剩余损伤及对浅P~+N结的影响(英文)

The residual damage is analysed by transmission electron microscopy (TEM) for BF2+, F+ + B+ and Ar+ + B+ implanted silicon after rapid thermal annealing(RTA). And the reverse leakage current of the implanted diodes is measured using a FJ-356 electrometer. The results show that 1 ) The residual damage due to BF2+ implantation is less than that of F+ + B + and Ar++ B+ implantation. 2) The reverse leakage current of BF2+ implanted diodes is less than that of F+ + B+ and Ar++ B + implanted diodes. 3) The reverse leakage current of F++B+ and Ar++ B+ implanted diodes increases with the increase of F+ and Ar+ energies, respectively. Therefore the physical behaviour of the interaction between molecular ion and silicon is different from that of the interaction between individual atom ion and silicon.     

p+-n-p+ BARITT-diode design

p+-n-p+ BARITT diodes have been designed to give maximum output power at X band frequencies. Computed output power against frequency shows good agreement with measured powers. The dominant effect of the maximum n region electric field on output power is demonstrated.     

C／C＋＋TEST

C++Test是来自于ParasSoft公司的用于C及C++单元测试的新工具,它使得发现和修改以前会迅速扩展并蔓延成更严重问题的错误变得更容易和有效.使用C++Test工具是完全自动化的,为了更快的测试,只需在文件中依次点击C++Test的打开、建立,就会完成测试.为了进行完整的测试,可以修改测试参数以使C++Test自动完成白盒、黑盒及逆向测试. 白盒测试用于测试代码结构.C++Test通过自动产生并运行测试用例,当它们接受不可预知输入时来检查文件、类、方法的行为.     

TVPON＋TVPCN＋EPON＋EPCN技术的实践应用

利用TVPON＋TVPCN＋EPON＋EPCN技术在有线广播电视网络中的完美结合,既实现了传统的广播式大容量信息的下行传输,又实现了互联网接入的双向宽带功能,并对接入网中的有源设备进行全程全网管理。     

Small-signal noise behaviour of companion p+-n-p+ and p+-n-v-p+ punchthrough microwave diodes

The frequency and current dependence of the noise factor of tuned microwave amplifiers, utilising punchthrough injection transit-time diodes, has been determined. Noise factors as low as 10 and 11 dB were obtained from companion p+-n-p+ and p+-n-v-p+ structures, respectively, when tuned to frequencies in the vicinity of 7.5 GHz.     

半绝缘GaAs中Mg~++P~+双注入研究

本文对Mg~+和P~+双离子注入半绝缘GaAs的行为进行了研究.发现不论是常规热退火还是快速热退火,共P~+注入都能有效地提高注入Mg杂质的电激活率,其效果优于共As~+注入,共P~+注入的最佳条件是其剂量与Mg~+离子剂量相同,电化学C—V测量表明,双注入样品中空穴分布与理论计算值接近,而单注入样品中则发生严重偏离,快速热退火较常规热退火更有利于消除注入损伤.     

F2+uF2+…+ukF2环上的循环码

在有限环F2＋uF2＋…＋u^k F2与F2之间定义一个新的Gray映射，证明了该映射是距离保持映射。考察了F2＋uF2＋…＋u^k F2环上循环码，得到了F2＋uF2＋…＋u^k F2环上循环码的生成多项式。最后，证明了F2＋uF2＋…＋u^k F2环上循环码在新定义的Gray映射下的像是F2上的准循环码。     

Experimental comparison of silicon p+-n-p+ and Cr-n-p+ transit-time oscillators

Punchthrough transit-time diodes have been constructed with both Schottky-barrier and diffused-junction emitters. The microwave and d.c. characteristics of these devices are strikingly similar. Either construction technique appears to be suitable for the future development of low-noise microwave sources.     

环F2+uF2+vF2+uvF2上(1+uv)-循环码

该文定义了有限非链环R=F2+uF2+vF2+uvF2上(1+uv)-循环码的相关概念,讨论了其与该环上循环码的关系,证明了此环上(1+uv)-循环码在关于齐次重量的等距Gray映射hom下的二元象是一个长为8n的4-准循环码, 并由此映射得到了一些好的二元线性准循环码。     

An Approximate Comparison Between n+-p-p+ and p+-n-n+ Silicon TRAPATT Diodes (Short Papers)

The difference in the ionization rates of holes and electrons in Si results in different properties of n+-p-p+ and p+-n-n+ TRAPATT diodes. An approximate analysis is presented which shows these differences and indicates superior performance in the n+-p-p+ structure.     

千兆以太网+时分复用+闲置光纤=宽带城域网

毫无疑问,世界正在向全光通信网快速迈进,电话、远程医疗、互联网会议、数字音乐、交互视频和网上金融等业务都将由光设备来发送和接收,并通过光纤来传输。向全光网发展长篇累牍的论述和几百次的会议得出了一个简单明了的结论,即市场对大容量、更灵活、更简单和更经济的宽带系统的需求将很快取代对传统铜线系统的需求。对不断增加的带宽需求而言,基于铜线的接入技术,如ISDN、DSL和Cable modem,仅仅能暂时作为“最后一公里”的解决方案。基于硅晶片的无线传输所提供的容量和速度更不能满足用户接入的需要。迫于全世界范围内对宽带…     

Temperature-dependent characteristics of MBE-grown GaAs p+-v-p+-v-n+ regenerative switching device

The thick GaAs p+-v-p+-v-n+ regenerative switching diode was fabricated by the MBE technique on n+-GaAs substrate. Temperature-dependent operational parameters, including switching voltage VS, switching current IS, holding voltage VH and holding current I, were investigated. It is found that VS, VH and IH decrease from 19 V, 3.6 V and 1.2 mA to 10.2 V, 2 V and 130 ?A, respectively, with decreasing measurement temperature from room temperature to 77 K, while IS increases from 5 ?A to 45 ?A. However, VS takes a more complicated `M?-shape characteristic from 77 K to 323 K which indicates a more complicated transport mechanism.     

VC+ +与Matlab的混合编程

主要从Matlab6p5和Visual C＋＋ 6．0之间编程接口出发，探讨C＋＋语言与Matlab混合编程的思路及详细的实现方案与实现难点，从而提高基于Matlab仿真软件的运行速度和代码执行的效率，扩展软件的应用范围，为在校学生和工程技术人员提供有效的借鉴。     

X band n+-p-p+ IMPATT diodes

Silicon IMPATT diodes, utilising holes as the drifting carrier, have been fabricated. An output power of 0.5 W with 12% efficiency at X band was obtained.     

基于Linux+Apache+Mysql+PHP OA系统的设计与实现

办公自动化系统(OA)是电子化信息系统(EMIS)的典型应用,在中小企业中有着广泛的运用,本文介绍是以Linux Apache Mysql PHP OA系统的基本架构和主要功能,并给出其中特有功能的系统的实现。     

利用TVPON＋TVPCN＋EPON＋EPCN构建广电特色大宽带

广电接入网大宽带既包括高带宽的双向传输,也包括大容量的广播式下行传输,两者融合构建成具有广电特色的大宽带.介绍TVPON、TVPCN和EPON、EPCN如何在有线广播电视网络改造和建设中实现完美结合,指出当前尽快实现有线广播电视网络大容量双向传输的一种建网思路.     

5G+云+AI 重塑泛互联网形态

<正>2019年,中国提前进入5G商用元年。5G将给移动互联网带来巨大变化,催生出许多意想不到的新应用,带来新的商业机会。目前,诸多互联网企业及传统企业都在抢滩5G,希望从5G中收获机遇。在5G这条高速公路上,由于带宽将不再是制约瓶颈,云端强大的计算力将得以充分利用,促使移动应用加速从终端侧向云端汇聚,客户端与服务端的边界将逐渐模糊。其次,终端也回归屏幕与人机交     

Punch-through currents in P+NP+ and N+PN+ sandwich structures—II: General low-injection theory and measurements

Analytical one-dimensional exponential expressions are derived for the current/voltage characteristics of the punch-through effect in devices where a certain bias voltage is needed to bring the device into punch-through (V_PT > 0) and where punch-through is already present in the non-biased condition (V_PT = 0). Measurements show that the theory can describe the current/voltage relations adequately at low current levels.