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nd-Tech

  • Next-Generation+Wireless+Technologies

    In the past few decades, a technological revolution has occurred that has changed the way we live in dramatic ways. This technological revolution is the result of the emergence and evolution of a wide variety of new wireless networking tech- nologies. Now people using these technologies are able to access the network and control many applications at will with their handheld devices anywhere, anytime. Although these technologies have made a long lasting impact in the revolution, it has also opened up various challenging issues which are yet to be resolved to make them more efficient and cost-effective. 

    标签: Next-Generation Technologies Wireless

    上传时间: 2020-05-31

    上传用户:shancjb

  • Opportunistic+Spectrum+Sharing

    Rapid growth of wireless communication services in recent decades has created a huge demand of radio spectrum. Spectrum scarcity and utilization inefficiency limit the development of wireless networks. Cognitive radio is a promising tech- nology that allows secondary users to reuse the underutilized licensed spectrum of primary users. The major challenge for spectrum sharing is to achieve high spectrum efficiency while making non-intrusive access to the licensed bands. This requires in- formation of availability and quality of channel resources at secondary transmitters, however, is difficult to be obtained perfectly in practice.

    标签: Opportunistic Spectrum Sharing

    上传时间: 2020-05-31

    上传用户:shancjb

  • Wideband+TDD

    This book is an outgrowth of the pioneering development work done by InterDigital Com- munication Corporation in 3rd Generation TDD WCDMA Technology. Many engineers and managers were involved in this development, which spanned a wide range of tech- nology areas, including system architecture, radio interface, radio modem design, radio resource management and hardware/software implementation. In addition, TDD WCDMA technology had many direct and indirect contributors across the globe in the context of the development of the 3GPP TDD WCDMA Standard.

    标签: Wideband TDD

    上传时间: 2020-06-01

    上传用户:shancjb

  • Fundamentals+of+EM+Design+of+Radar

    In the present era, low observability is one of the critical requirements in aerospace sector, especially related to defense. The stealth technology essentially relates to shaping and usage of radar absorbing materials (RAM) or radar absorbing struc- tures (RAS). The performance of such radar cross section (RCS) reduction tech- niques is limited by the bandwidth constraints, payload requirements, and other structural issues. Moreover, with advancement of materials science, the structure geometry no longer remains key decisive factor toward stealth.

    标签: Fundamentals Design Radar of EM

    上传时间: 2020-06-06

    上传用户:shancjb

  • Cogeneration+and+District+Energy+Systems

    District energy (DE) systems use central heating and/or cooling facilities to provide heating and/or cooling services for communities. The advantages of district energy over conventional heating and cooling include improved efficiency, reliability and safety, reduced environmental impact, and for many situations better economics. DE systems can be particularly beneficial when integrated with cogeneration plants for electricity and heat, i.e., with combined heat and power (CHP) plants. One of the main impediments to increased use of cogeneration-based district energy is a lack of understanding of the behavior of integrated forms of such systems. This book is aimed at providing information on district energy and cogeneration tech- nologies, as well as systems that combine them.

    标签: Cogeneration District Systems Energy and

    上传时间: 2020-06-07

    上传用户:shancjb

  • Stable_adaptive_neural_network_control

    Recent years have seen a rapid development of neural network control tech- niques and their successful applications. Numerous simulation studies and actual industrial implementations show that artificial neural network is a good candidate for function approximation and control system design in solving the control problems of complex nonlinear systems in the presence of different kinds of uncertainties. Many control approaches/methods, reporting inventions and control applications within the fields of adaptive control, neural control and fuzzy systems, have been published in various books, journals and conference proceedings.

    标签: Stable_adaptive_neural_network_co ntrol

    上传时间: 2020-06-10

    上传用户:shancjb

  • 硬件工程师笔试题大全及答案21页

    硬件工程师笔试题大全及答案21页 硬件工程师笔试题大全及答案1、请列举您知道的电阻、电容、电感品牌(最好包括国内、国外品牌)。 电阻:RALEC旺诠、ROYALOHM、SUPEROHM、UniOhm、TA-I大毅、TDK、TOKEN、VISHAY、YAGEO、广东风华 电容:AVX、KEMET、Kyocera、muRata、NEC、nichicon、Panasonic、SAMSUNG、SANYO、TAIYO YUDEN、TDK、VISHAY、YAGEO、广东风华、 电感:AEM、EPCOS、ETC、Gausstek丰晶、muRata、sumida村田、Sunlord顺络、TAI-TECH台庆、TDK、TOKEN、TOREX、VISHAY、WE、YAGEO国巨、柯爱亚、科达嘉、奇力新、千如电子、捷比信、紫泰荆、肇庆英达、广东风华 2、请解释电阻、电容、电感封装的含义:0402、0603、0805。表示的是尺寸参数。 0402:40*20mil;0603:60*30mil;0805:80*50mil。 3、请问电阻、电容、电感的封装大小分别与什么参数有关?电阻封装大小与电阻值、额定功率有关;电容封装大小与电容值、额定电压有关;电感封装大小与电感量、额定电流有

    标签: 硬件工程师

    上传时间: 2022-03-25

    上传用户:ttalli

  • HI-TECH C Compiler for PIC18 MCUs (PRO) Update v9.

    上传文件为picc18编译器。包含破解软件在内。

    标签: C Compiler for pic18 mcus pro update

    上传时间: 2022-05-24

    上传用户:

  • cadence-virtuoso的使用简介

    全文将用一个贯穿始终的例子来说明如何绘制版图。这个例子绘制的是一个最简单的非门的版图。S2-1建立版图文件使用library manager.首先,建立一个新的库myLib,关于建立库的步骤,在前文介绍cdsSpice时已经说得很清楚了,就不再赘述。与前面有些不同的地方是:由于我们要建立的是一个版图文件,因此我们在technology file选项中必须选择compile a new tech file,或是attach to an exsiting tech file。这里由于我们要新建一个tech file,因此选择前者。这时会弹出load tech file的对话框,如图2-1-1所示。在ASCII Technology File中填入csmclo0.tf即可。接着就可以建立名为inv的cel了。为了完备起见,读者可以先建立inv的schematic view和symbol view(具体步骤前面已经介绍,其中pmos长6u,宽为0.6u。nmos长为3u,宽为0.6u。model仍然选择hj3p和hj3n)。然后建立其layout view,其步骤为:在tool中选择virtuoso-layout,然后点击ok。

    标签: cadence virtuoso

    上传时间: 2022-07-20

    上传用户:

  • 最新华为pcb技术规范

    最新华为pcb技术规范行温度       110°C130°C150℃MOT(最大运行温度)到UL 746130°C150°C180°C 热阻要求定义:温度:             时间:             气候:   抗热震性 -40°C至+ 85°C老化循环:         100 200 500 1000 -40°C至+ 110°C老化循环:         100 200 500 1000 -40°C至+ 125°C老化循环:         100 200 500 1000老化循环:           特别:              低/高温时间:2小时/ 2小热稳定性,         即焊料电阻(即无铅焊料)波峰焊接<250°C<260°C<270°C<280°C 回流焊接周期:2<250°C<260°C<270°C<280°C 气相焊接<250°C<260°C<270°C最大<280°C 产品应用中的温度温度:       时间:        气候:     机械要求■机械稳定性达到:+ 85°C+ 110°C+ 130°C+ 150°C ■扭曲  <0.5%<0,75%<1,0%■x/y轴的CTE单位[ppm / K]                <18                     <14            <10 ■z轴的CTE(低于Tg)单位[ppm / K]<70                  <50                <30 ■z轴的CTE(高于Tg)单位[ppm / K]<300           <260                      <230 ■铜附着力单位[N /mm²]<0,80,8到1,6> 1,6 ■重量单位[kg /dm²]:nd

    标签: pcb规范

    上传时间: 2022-07-22

    上传用户: