超宽带无线通信技术简介

本文首先介绍了超宽带（UWB）技术的定义及其频谱规划情况．分析了UWB的调制与多址技术,然后介绍了目前IEEE 802.15.3 SG3a建议使用的UWB路径损耗模型及多径信道模型,最后展望了UWB技术的应用前景及目前发展状况与需要进一步研究的问题。     

超宽带无线通信技术

无线技术在通信发展进程中一直扮演着重要角色。伴随着移动通信十几年来的蓬勃发展以及3G、B3G等概念的日益普及，无线家族中的另一成员——短距离宽带无线接入技术近年来异军突起。从蓝牙、HomeRF到IEEE802．11(即Wi—Fi)系列，     

超宽带无线通信技术

超宽带(UWB)具有传输速率高、通信距离短、平均发射功率低等特点，非常适合于短距离高速无线通信。本文介绍 UWB 的原理及主要技术特点，详细比较了 UWB 通信与 IEEE802.11、IEEE802.15.3、Home RF 和 Bluetooth 等技术的异同，并展望了 UWB 的应用前景。     

基于超宽带无线通信技术的研究

超宽带无线通信是一种采用脉冲调制的无线通信方式，具有高系统容量、良好的抗多径能力和低功耗低成本的特点。本文对无线通信技术的基本定义进行了阐述，重点介绍了其性能特点和研究现状，并讨论了其面临的机遇和挑战。     

超宽带无线通信技术

超宽带(UWB)具有传输速率高、通信距离短、平均发射功率低等特点,非常适合于短距离高速无线通信.文章对UWB的发送接收技术和信道建模方式进行了讨论,指出UWB将定位于各种消费类电子设备和终端间的高速无线连接.对于IEEE的UWB标准,文章认为由于目前形成了脉冲无线电和多频带正交频分复用(OFDM)两大方案,因此最终采用哪种方案还需等待.     

UWB超宽带无线通信技术及其发展前景

本文首先介绍了超宽带技术的定义，描述了超宽带技术的特点和信道模型，阐述用于超宽带系统常用的多址方式和调制方式，给出了超宽带通信收发机结构，最后分析了国内外超宽带技术发展应用的前景。     

超宽带技术概述

介绍了无线通信领域的新技术超宽带无线电（UWB）的技术优点和调制方式，并将UWB与其他短距离无线通信进行了对比，最后简单分析了UWB在下一代无线通信中的应用前景。     

浅析超宽带无线电技术

广义超宽带技术（Ultra WindeBand,UWB）是指以极窄脉冲方式进行无线发射和接收的特种技术，其特殊之处在于完全摆脱了一般无线收发中必须采用载波调制的传统手段，成为在对域出直接操作的无线技术，因此也称作脉冲无线电（Impuise Radio）,时域（Time Domain）或无载波（Carrier Free）无线电技术。     

超宽带技术原理及其应用简介

首先介绍了UWB技术的原理,并与其它短距无线通信技术作了性能比较,最后给出了其应用前景和面临的技术挑战.     

超宽带技术在未来无线通信中的应用

首先给出了超宽带技术(UWB)的概念,详细叙述了超宽带技术的基本原理和研究现状,阐述了超宽带的关键技术及在未来无线通信中的应用,给出了超宽带技术的技术规范、技术要求和国内外超宽带技术中关键技术的研究现状和面临的挑战,最后介绍了超宽带技术的发展动态。     

超宽带无线通信技术概述

主要介绍了超宽带(UWB)无线通信技术的起源、概念及其基本工作原理，包括信号产生、系统构成、天线、接收机、调制方式等，阐述了UWB中的关键技术及性能特点，对UWB的局限性作了简要的介绍。     

Fluid coding and coexistence in ultra wide band networks

Time Hopping Ultra Wide Band (TH–UWB) commonly encodes the data symbols by shifting the position of the transmitted pulses by a quantity that is quantized over the inter-pulse interval range. In this paper, we relax the hypothesis of a discrete value for the time shift introduced by the TH code, by considering the possibility of generating real-valued codes that introduce time hopping in a “fluid” way. The effect on the power spectral density of generated signals is analyzed, and application of fluid coding to multiple access and to network coexistence is investigated by simulation. Portions of this work were presented at the 2005 2nd International Workshop Networking with Ultra Wide Band, Workshop on Ultra Wide Band for Sensor Networks [M.G. Di Benedetto, G. Giancola, D. Domenicali and P. Ingargiola “Fluid Coding in Time Hopping Ultra Wide Band Networks,” Proceedings of the IEEE 2nd International Workshop Networking with Ultra Wide Band—Ultra Wide Band for Sensor Networks, July 2005, Rome, Italy]. Daniele Domenicali took his Laurea degree in Telecommunications Engineering at the University of Rome La Sapienza in 2004. In November 2004 Domenicali wins the open competition for PhD scholarship in Information and Communication Engineering. He is teaching assistant for the course of “UWB Communication Systems” conducted by Professor Maria Gabriella Di Benedetto at the University of Rome La Sapienza. His research activity includes Pulse Shaping and the related modulation and coding techniques (Time Hopping Coding, PAM and PPM Modulation). Particular attention is paid to the effects produced in the Power Spectral Density, in order to find solutions capable of optimizing spectrum occupation while meeting the constraints imposed by emission masks. Daniele Domenicali is involved in the European Network of Excellence HYCON (Hybrid Control: Taming Heterogeneity and Complexity of Networked Embedded Systems). Guerino Giancola received the “Laurea” degree (magna cum laude) in Telecommunications Engineering, and the Ph.D. degree in Information and Communication Engineering from University of Rome La Sapienza, in 2001 and 2005, respectively. He is currently a research affiliate at the INFOCOM Department at University of Rome La Sapienza, where is actually holding the course of “Electrical Communications” for the degree on Electronic Engineering. His research interests include the analysis and modelling of Multi User Interference in Impulse Radio systems, and the design of Medium Access Control functions and protocols for UWB ad-hoc networks. Guerino Giancola recently co-authored with Prof. Maria-Gabriella Di Benedetto a book on Ultra Wide Band from radio to the network, titled “Understanding Ultra Wide Band Radio Fundamentals” and published by Prentice Hall in June 2004. He is now involved in the European project “PULSERS – Pervasive Ultra wideband Low Spectral Energy Radio Systems” and in the European Network of Excellence “HYCON- Hybrid Control: Taming Heterogeneity and Complexity of Networked Embedded Systems”. Guerino Giancola is a member of the IEEE Communication Society. Maria-Gabriella Di Benedetto obtained her Ph.D. in Telecommunications in 1987 from the University of Rome La Sapienza, Italy. In 1991, she joined the Faculty of Engineering of University of Rome La Sapienza, where currently she is a Full Professor of Telecommunications at the Infocom Department. She has held visiting positions at the Massachusetts Institute of Technology, the University of California, Berkeley, and the University of Paris XI, France. In 1994, she received the Mac Kay Professorship award from the University of California, Berkeley. Her research interests include wireless communication systems and speech science. From 1995 to 2000, she directed four European projects for the design of UMTS. Since 2000, she has been active in fostering the development of Ultra Wide Band (UWB) radio communications in Europe. Within the 5th framework, she directed for the Infocom Dept. two European projects (whyless.com and UCAN) aimed at the design and implementation of UWB ad-hoc networks. Currently, within the 6th EU Framework, her “Networking with UWB” research group participates in the PULSERS Integrated Project which will integrate UWB research and development in Europe for the next years, and in the LIAISON Integrated Project as regards the application of UWB to location-based services. She also participates in the HYCON network of excellence. Dr. Di Benedetto is co-edited several Special Issues on UWB communications and networks for several Journals including IEEE JSAC, Journal of Communications and Networks, Mobile Networks and Applications, Eurasip. In 2004, Dr. Di Benedetto co-authored with G. Giancola the first published book on UWB for communications titled “Understanding Ultra Wide Band Radio Fundamentals” and published by Prentice Hall. She recently completed the co-edition of two new books on UWB that will be published by 2005: UWB Communication Systems - A comprehensive overview, with T. Kaiser, D. Porcino, A. Molisch, and I. Oppermann, Hindawi Publishing Corporation, 2005, andUltra Wideband Wireless Communications with H. Arslan and Z.N. Chen, John Wiley & Sons, Inc., 2005.     

无线通信系统中的低码率空时网格码

空时网格编码能在频带利用率、分集增益、调制方式与编码网络图复杂度之间达到最佳的折衷。本文给出了几种低码率空时网格码的好码。理论分析和系统仿真表明,在相同的频带利用率下,该空时网格码可具有比空时块码级联卷积码具有更好的误码率性能,更适合于对频带利用率要求不高的功率受限无线通信系统。     

基于同步条件下短波宽带通信相关技术研究

现阶段短波通信主要针对频谱管理、信道选择以及波形设计等方面进行研究,用以支持比传统3kHz带宽更宽的短波通信信道。在同步技术越来越成熟的阶段,未来短波通信的主要研究方向将由窄带向宽带发展。该文主要针对短波通信的性质,分析短波通信在同步条件下宽带的优越性和可行性。     

无线激光通信技术

无线激光通信（WLC），又称自由空间通信或者大气激光通信。是一种以激光为载体的点对点通信．本文介绍了无线激光通信系统的工作原理，通过计算得出了系统的通信能力和通信质量将主要取决于激光光束的传播情况的结论，讨论了系统通信波长的选取，其发射系统，光学天线以及接收系统的设计关键。以及无线激光通信和当前主流通信方式的比较。展望了无线激光通信系统广阔的发展前景。     

UWB-新型宽带无线接入技术

本文主要介绍了超宽带(UWB)无线通信技术的起源、概念及其基本工作原理,并总结了UWB的性能特点,对UWB的局限性也作了简单的介绍。     

无线激光通信技术

无线激光通信是一种以激光为载体的点对点通信,本文介绍了无线激光通信系统的工作原理,以及通过计算得出了系统的通信能力和通信质量将主要取决于激光光束的传播情况的结论,讨论了系统通信波长的选取,其发射系统,光学天线以及接收系统的设计关键,并提出了一种收发一体、光电分离的系统结构.以及无线激光通信和当前主流通信方式的比较.展望了无线激光通信系统广阔的展前景.     

蓝牙无线通信技术

蓝牙技术作为一种近距离无线连接的全球开放规范，已经得到了全球众多大企业的支持。本文对蓝牙无线通信的技术及系统组成进行了详细的论述，并对其应用及未来的发展前景作了讨论。