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1.
箔条和箔片的性能特性及其应用和趋势   总被引:6,自引:0,他引:6  
谭显裕 《雷达与对抗》1999,(3):10-17,56
从箔条和箔片用于干扰雷达测和扰乱、迷惑、转移或者引诱进攻出发,详细论述箔条、箔条云及箔片、箔片云的雷达散射截面、带度、平移速度、下降速度及转动等情况,空间和时间我、水平和垂直极化性能、多普勒频移效应以及频谱展宽特性等,通过箔条和箔片有效成火控雷达实例,提出对抗火控雷达的三个重要因素及其采取的对策。  相似文献   

2.
The author observes that the social fabric of engineering, the support infrastructure of the profession, and the political and economic systems of the world are undergoing shifts that affect what engineering is, how it is accomplished, and what it should do. He asks what these changes mean in terms of the educational system and explores a few of these issues that lie between academia and the industrial environment beyond. He discusses the engineering curriculum as seen from industry, the role of continuing education, research in academia  相似文献   

3.
The deposition of silicon carbide thin films and the associated technologies of impurity incorporation, etching, surface chemistry, and electrical contacts for fabrication of solid-state devices capable of operation at temperatures to 925 K are addressed. The results of several research programs in the United States, Japan and the Soviet Union, and the remaining challenges related to the development of silicon carbide for microelectronics are presented and discussed. It is concluded that the combination of α-SiC on α-SiC appears especially viable for device fabrication. In addition, considerable progress in the understanding of the surface science, ohmic and Schottky contacts, and dry etching have recently been made. The combination of these advances has allowed continual improvement in Schottky diode p-n junction, MESFET, MOSFET, HBT, and LED devices  相似文献   

4.
姜辉 《现代电子技术》2007,30(10):185-188
在日本电视广播的发展过程中,电视信号技术、电视节目转播技术、发射机技术以及天线技术等发挥了不可替代的作用。这些技术在长达60多年的模拟电视广播中被大量的开发、使用,尤其是射频相关技术为日后地面数字电视广播的发展提供了重要参考。主要介绍了日本电视广播中该相关技术的发展,并进行了讨论。  相似文献   

5.
6.
Over the last 40 years in the semiconductor industry, one of the most reliable truths has been that "thepath forward is through integration." Moore's law and its various derivatives and cousins have illustrated how greater integration has provided tremendous benefits in cost, power, size, and performance. While shrinking process lithography has been a critical enabler of this trend, we should remember that tremendous innovation in device technology, circuits, system architecture, computer aided design (CAD), packaging, and many other areas have been necessary as well. The exponential integration phenomenon has not been limited to memory and microprocessors: mixed signal and radio functions have also seen striking advances in integration over the last 20 years, from cell phones to wireless LANs, integrated "systemon-a-chip" (SOC) transceivers have become prevalent in the circuits conferences, journals, and - in some applications - have even made it into commercial mainstream products.  相似文献   

7.
信号与系统课程是高等院校电类专业一门重要的专业基础课程,本文以西安明德理工学院智能制造与控制技术学院的信号与系统课程建设与教学改革为例,介绍了我院在信号与系统课程资源建设和教学改革中的探索和实践。实践证明,本文提出的五维一体化线上线下课程资源建设和混合式教学改革能够有效推动教与学两个方面的变革,有效提高课程教学质量,为同类兄弟院校的同类课程建设和教学改革起到一定的借鉴作用。  相似文献   

8.
压电/电致伸缩材料及驱动器的新技术与应用   总被引:8,自引:2,他引:6  
压电/电致伸缩驱动器是一种广泛使用的驱动器,文章概括总结了几种压电/电致伸缩新材料的发展方向,同时还介绍了几种新型驱动模式和超声电机的研究动态,并对压电/电致伸缩驱动器的发展前景予以展望。  相似文献   

9.
Cellular architecture partitioning can improve the performance of telecommunications systems. The model proposed by the author allows for changing the cell size for different services and the number of users. The cell size that will ensure the best possible performance and quality of service can be derived by the model. The main task of a telecommunication system is call processing. This includes identifying incoming calls, establishing a communication path for the duration of the connection, and disconnecting the call after the conversation has ended. Call processing uses different components of the software architecture and involves processes and messages performing different functions and accessing various resources. In addition, the system requires administration and maintenance that also involves processes using different resources  相似文献   

10.
根据广电5G未来建设的发展,结合当前传输和架构研究和测试的需求,提出搭建广电5G传输研究测试平台的意义,并对平台进行构建,最后对平台的各个组成部分进行了详细阐述。  相似文献   

11.
《IEE Review》1994,40(1):26-27
The author explains how the kanban, or just-in-time, approach to manufacturing works. He then draw analogies with data communication systems and in particular asynchronous transfer mode and routing switches. These analogies are illuminating in that they show how alike the two disciplines are, and how they have arrived at similar solutions to similar problems. The author studies the differences between the two fields which could lead to communications engineers learning something from the ideas of manufacturing engineers, and vice versa  相似文献   

12.
面向国家“碳达峰”与“碳中和”的“双碳”战略需求,移动通信与网络需要在满足不断增长的业务需求前提下大幅度降低全网能耗,因此需要研究使用更少的能量传递更多信息(SMILE, send more information bits with less energy)的理论与技术。为了应对该挑战,仅靠无线传输技术的改进和硬件实现水平的提高是远远不够的,需要从系统和网络的角度探索能量的高效利用机理与方法。从能量的“节流”和“开源”2个维度展开,并针对日益增长的计算能耗给出解决方案。具体地,通过引入超蜂窝网络架构实现网络的柔性覆盖与弹性接入,使业务基站和边缘服务器在业务量较低时可以进入休眠状态,减少能量的浪费(即“节流”)。同时,大量引入可再生绿色能源(即“开源”),通过能量流与信息流的智能适配,大幅降低电网的能耗。进一步地,通过网络功能虚拟化、通信与计算资源的高能效协同,以及移动智能体的分布式计算与协同等手段,实现绿色计算与人工智能算法。  相似文献   

13.
钟东 《移动信息》2023,45(11):16-18
我国已经进入信息化时代,其中信息传播的方式发生了翻天覆地的变化。如果一直采用固定的数据传播方式和播放模式,则无法满足主流媒体个性化发展的需要,违背了时代发展的浪潮,难以进行有效的传播。基于此,文中研究了5G通信技术的优势以及5G通信技术与广播电视技术的融合,探讨了5G通信技术与广播电视技术融合的策略,以期促进广播电视行业的发展。  相似文献   

14.
胡永富  解静  吴建福  齐文雯  牟研娜 《半导体光电》2020,41(2):273-277, 282
介绍了一种轻小型推扫视频一体化微纳遥感相机的综合优化设计思路。系统设计时综合考虑星地一体化处理,采用大F数RC系统降低产品光机体积重量;电子学采用商用货架产品加固技术实现高性能同时降低成本,星上数据处理采用数字TDI技术实现面阵相机推扫视频一体化成像,大幅提升成像效能。采用该方法设计的微纳遥感相机具备视频、推扫、条带等多种工作模式,满足不同应用场景需求。该技术在欧比特视频相机等微纳遥感载荷的设计及研制中进行了应用,在轨获取了高品质的视频及遥感图像,在商业遥感载荷市场具有广阔的应用前景。  相似文献   

15.
探讨了快走丝线切割机床CAD/CAM系统打色成,实现的技术关键,着重介绍了CAD/CAM系统的工艺数据库的建立。  相似文献   

16.
李广成 《世界电信》2001,14(1):21-25
目前所谓的全光网络一般指基于DWDM传送技术的光传送网络(OTN)。由于OTN的节点采用OADM和OXC技术,为解决目前点到点的DWDM技术在应用中不能实现灵活组网和当网络失效时不能有效进行保护的问题提供了一种解决方法,使得OTN具有传输容量大、组网灵活、网络具有可扩展性和可重构性、易于升级等特点,可透明传输具有代码格式的不同速率等级的用户数字信号,能够同时适应用户信号种类用服务种类不断增长的需求。  相似文献   

17.
广播电视发射机房最核心的工作就是确保安全播出,因此加强对广播电视发射台发射机房的维护就十分重要,这样可尽可能避免机房设备出现故障,保障广播电视信号的传输,根据工作实践系统论述了对发射机房和数字电视发射机的管理和维护工作。  相似文献   

18.
Today's microprocessors require careful analysis of their thermal behavior both at design time as well as at runtime. However, accurate prediction of thermal behavior is possible only through simulations due to the complexity and the high dynamicity of their operation. Unfortunately, accurate simulations of such complex systems are computationally intensive, therefore time consuming, while on the other hand, simplified models often cause mispredictions leading to overdesign and lowered performance. In our work, we propose a new discrete-time method of assessment of the run-time temperature of a processor based on an approximation of its instructions-per-cycle (IPC) by a finite Fourier series expansion. Our method is AC-based, and shows significant increase of accuracy in comparison to well-known DC (average)-based models. Furthermore, we provide a new Dynamic Voltage and Frequency Scaling (DVFS) model based on our estimations.  相似文献   

19.
张伟功  周继芹  李杰  王晶  丁瑞  邓哲  王嘉佳  杜瑞 《电子学报》2015,43(9):1776-1785
本文针对航天航空等领域综合电子系统在小型化、一体化设计及信息综合利用等方面的需求,提出一种可动态重构的高速串行通信总线(UM-BUS),采用N(≤32)通道并发传输,通信速率可达6.4Gbps,采用总线型拓扑结构,最大通信距离40m,支持最多30个节点直接互连,具有远程存储访问能力,采用命令应答式协议提供QoS与实时性保证;通过并发通道相互冗余与动态重构,在允许50%性能降低的情况下,能够对N/2通道故障动态容错.在UM-BUS总线基础上,本文提出一种新型的"接入式"体系结构模型,在不改变系统逻辑结构的前提下,能够突破机箱结构限制,将逻辑功能分散嵌入到控制测量对象内部,实现功能模块"接入即用",使得综合电子系统一体化设计成为可能.  相似文献   

20.
朱恒飞 《中国有线电视》2013,(11):1306-1311
随着广播电视传输覆盖技术的不断更新与发展,经过几十年的建设积累,目前市县广播电视已基本实现广播与电视并重、模拟与数字并举、有线与无线并用、城市与农村同步的综合无缝覆盖。以昭通市广播电视覆盖网络为参考,从技术角度论述市县广播电视综合覆盖与监测系统建设模式,供参考。  相似文献   

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