首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   285篇
  免费   6篇
综合类   1篇
物理学   4篇
无线电   286篇
  2022年   1篇
  2021年   2篇
  2020年   10篇
  2019年   3篇
  2018年   1篇
  2017年   5篇
  2016年   7篇
  2015年   11篇
  2014年   15篇
  2013年   15篇
  2012年   8篇
  2011年   12篇
  2010年   6篇
  2009年   11篇
  2008年   21篇
  2007年   13篇
  2006年   28篇
  2005年   26篇
  2004年   27篇
  2003年   23篇
  2002年   25篇
  2001年   16篇
  2000年   5篇
排序方式: 共有291条查询结果,搜索用时 250 毫秒
1.
Mehta  Vipin  El Zarki  Magda 《Wireless Networks》2004,10(4):401-412
Communicating with sensors has long been limited either to wired connections or to proprietary wireless communication protocols. Using a ubiquitous and inexpensive wireless communication technology to create Sensor Area Networks (SANs) will accelerate the extensive deployment of sensor technology. Bluetooth, an emerging, worldwide standard for inexpensive, local wireless communication is a viable choice for SANs because of its inherent support for some of the important requirements – low power, small form factor, low cost and sufficient communication range. In this paper we outline an approach, centered on the Bluetooth technology, to support a sensor network composed of fixed wireless sensors for health monitoring of highways, bridges and other civil infrastructures. We present a topology formation scheme that not only takes into account the traffic generated by different sensors but also the associated link strengths, buffer capacities and energy availability. The algorithm makes no particular assumptions as to the placement of nodes, and not all nodes need to be in radio proximity of each other. The output is a tree shaped scatternet rooted at the sensor hub (data logger) that is balanced in terms of traffic carried on each of the links. We also analyze the scheduling, routing and healing aspects of the resulting sensor-net topology.  相似文献   
2.
蓝牙与IEEE802.11g无线局域网(Wireless Local Area Network,WLAN)都工作在2.4GHz频段上,因此它们之间存在一定的干扰。分析了蓝牙与IEEE802.11g通信系统之间的干扰,并提出了解决这一问题的两种方法:自适应跳频和删除标记法,并对两种方法的性能做了比较。  相似文献   
3.
韩兆福 《电子工程师》2005,31(10):77-79
蓝牙技术是一种短距离无线通信技术,具有低成本、低功耗、灵活、快速、抗干扰能力强等特点,目的是取代终端的连接电缆.为提高部队的作战效能,采用蓝牙技术和计算机测量与控制技术,研制了机载火控故障诊断系统;该系统在实际应用中取得了良好效果,并具有诊断结果准确、自动化程度高、工作稳定可靠、操作简便、易于转移和维护等优点,为技术人员进行机载火控系统的性能检测与故障诊断提供了便利.  相似文献   
4.
针对现在流行笔筒功能单一、缺少互动、人性化程度低等问题,介绍了一种基于STM32单片机的智能笔筒的设计与实现方法。该设计将电子元素与古朴笔筒有机结合,采用集成化的硬件设计方案,包括液晶显示、人体感应、MP3解码和文件存储等模块,支持热插拔,并可通过蓝牙与Android或IOS 智能设备进行数据交互,使用者可根据自身需求,个性化地设置属于自己的笔筒。  相似文献   
5.
蓝牙自适应跳频序列性能优越,有着广泛的应用前景.通过仿真计算,分析了蓝牙自适应跳频序列的频率均匀性、汉明相关特性、跳频间隔分布特性、序列的线性复杂度、组网特性和系统容量.  相似文献   
6.
系统采用蓝牙无线与计算机网络相结合的传输方式,用户在计算机应用程序界面上对多路被控对象的工作状态和工作时间进行设置,同时也可以在用户界面上显示被控对象的工作状态。系统通过对PC微型网络转串口模块及其计算机界面的调试,实现了基于PC网络的控制系统的实际方案。  相似文献   
7.
基于窄带低噪声放大器理论,设计了一种2.4 GHz,具有低功耗、低噪声和良好匹配性等优点的新型BiFET结构SiGe BiCMOS低噪声放大器。采用TSMC 0.35μm SiGe BiCMOS工艺库,利用SpectreRF软件的仿真结果显示,该电路具有2.27 dB低噪声系数,11.5 dB正向增益;2 V工作电压下,其功耗仅为6.1 mW。研究结果表明,该低噪声放大器在射频蓝牙系统中具有一定的应用前景。  相似文献   
8.
IrBurst is a session/presentation layer protocol dedicated for high speed large volume information transfer over IrDA links. The protocol is developed by IrDA in order to complement the existing protocol OBEX which is best suited for small files. This paper presents a mathematical model for IrBurst over the IrDA protocol stacks taking into account the presence of bit errors and multiple simultaneously applications. The performance of IrBurst is examined considering TinyTP buffer sizes and the number of IrBurst application connections as parameters. The contribution of this work is to develop a mathematical model for IrBurst, investigate the compatibility of IrBurst to low layer protocols, as well as providing suitable design guidelines for IrDA devices for high performance of IrBurst. Pi Huang received the B.Sc. degree in Electrical and Electronic Engineering from University of Central Lancashire, U.K., in 2001, the M.Sc. degree in Telecommunications from University College London, U.K., in 2002 and the Ph.D degree in the Personal Wireless Networks and Outdoor Optical Links from Bournemouth University, U.K., in 2006. He is currently working in wireless solution division of British Telecom. His research focuses on performance modelling and analysis as well as discrete-event simulation of wireless communication protocols and wireless communication networks. He has published over 20 papers in the areas of wireless communications. Anthony C. Boucouvalas has worked at GEC Hirst Research Centre, and became Group Leader and Divisional Chief Scientist until 1987, when he joined Hewlett Packard (HP) Laboratories as Project Manager. He joined Bournemouth University in 1994 and became a Professor in Multimedia Communications in 1996, and in 1999 became Director of the Microelectronics and Multimedia Research Centre. His current research interests span the fields of wireless communications, optical fibre communications and components, multimedia communications, and human-computer interfaces, where he has published over 200 papers. He has contributed to the formation of IrDA as an industry standard and he is now a Member of the IrDA Architectures Council. He is a Fellow of Fellow of the Royal Society for the encouragement of Arts, Manufacturers and Commerce, (FRSA) and a Fellow of IEE, (FIEE). In 2002 he became a Fellow of the Institute of Electrical and Electronic Engineers (FIEEE), for contributions to optical fibre components and optical wireless communications. He is an Editor of numerous Journals and in the Organising committee of many conferences.  相似文献   
9.
付仕明  黄俊伟 《通信技术》2007,40(11):186-188
文中从接入点结合Bluetooth TD-SCDMA手机出发,设计了一种无线局域网应用方案.从功能上讲相当于通过Bluetooth建立无线微微网,并以TD-SCDMA手机为主机平台建立,充分利用了TD-SCDMA网络的高传输速率和高覆盖率,实现微微网内所有从设备都能通过TD-SCDMA手机实现高速无线上网.首先,文中论述了TD-SCDMA手机和Bluetooth技术,然后在这基础上提出了应用方案.最后,阐述了方案的关键技术.  相似文献   
10.
基于蓝牙的心肺音采集系统   总被引:1,自引:0,他引:1  
心脏疾病目前已经成为致死率第一的疾病。学者们正在致力于研究各种治疗方式,以从心脏病手中挽救人们的生命。而目前我国的心血管发病率在逐年增加,心血管课题也成为一个重要课题,心血管疾病也越来越受到人们的重视。本文研究了心肺音采集系统的适配电路,阐述了可分离心、肺音的多功能无线可视化电子听诊器的应用前景。针对可分离心、肺音的多功能无线可视化电子听诊器工作原理确定了适配电路的选择方案。详细介绍了各部分电路的功能,构成低功耗、低成本的硬件平台,实现基于蓝牙的心肺音采集系统。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号