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1.
高速宽带应用的毫米波CMOS集成电路   总被引:3,自引:1,他引:3  
近年来,随着可应用于几个Gb/s无线通信的非许可60GHz频段的开放,低成本的毫米波单片集成电路已成为研究和开发的热点。论文简述了CMOS射频集成电路的发展历史,介绍了IEEE 802.15.3工作组提出的60GHzISM毫米波工作频段的特性,阐述了毫米波CMOS集成电路设计的若干关键技术。  相似文献   

2.
Uncompressed high-definition video streaming over wireless personal area networks is a challenging problem because of the high data rate requirement and channel variations. With the advances in RF technology and the huge bandwidth available worldwide in the 57?66 GHz millimeter-wave unlicensed spectrum, mmWave WPANs that can support multigigabit transmission are being developed. However, compared to low-frequency signals (2.4 or 5 GHz), mmWave signals are more fragile; indeed, the propagation losses are significantly higher. In this article we present an mmWave system for supporting uncompressed HD video up to 3 Gb/s. The system includes various efficient error protection and concealment schemes that exploit unequal error resilience properties of uncompressed video. Some of them have been adopted in the emerging 60 GHz WPAN standards such as WirelessHD, ECMA TC48, and IEEE 802.15.3c. Simulations using real uncompressed HD images indicate that the proposed mmWave system can maintain, under poor channel conditions, good average peak-signal-to-noise-ratio and low video quality metric scores.  相似文献   

3.
王忠思  黄辉  邵晓 《通信电源技术》2009,26(4):42-44,48
UWB是目前最理想的低功耗、高带宽短距离无线通信技术。文中通过研究UWB无线通信的关键技术,指出其性能优点及局限性,阐明了UWB技术在军用和民用方面的应用前景。  相似文献   

4.
This article addresses basic issues regarding the design and development of wireless access and wireless LAN systems that will operate in the 60 GHz band as part of the fourth-generation (4G) system. The 60 GHz band is of much interest since this is the band in which a massive amount of spectral space (5 GHz) has been allocated worldwide for dense wireless local communications. The article gives an overview of 60 GHz channel characteristics and puts them in their true perspective. In addition, we discuss how to achieve the exploitation of the abundant bandwidth resource for all kinds of short-range communications. The main tenor is that an overall system architecture should be worked out that provides industry with plenty of scope for product differentiation. This architecture should feature affordability, scalability, modularity, extendibility, and interoperability. In addition, user convenience and easy and efficient network deployment are important prerequisites for market success. This article discusses these features and indicates a number of key research topics  相似文献   

5.
随着人们对短距离无线通信技术的需求越来越强烈,短距离无线通信技术得到快速发展和广泛运用,并日益走向成熟。文中阐述了短距离无线通信技术的概况,以及几种常见短距离无线通信技术类型的特点,探讨了其优势及运用方向。  相似文献   

6.
黄擘 《信息技术》2012,(6):161-163
超宽带(UWB)是一种无载波通信技术,有人称它为无线电领域的一次革命性进展,认为它将成为未来短距离无线通信的主流技术。UWB系统为了提高数据速率,应用了超短基带丰富的GHz级频谱,这就对基带处理和传输数据提出了很高的要求。在基于Xilinx Virtex-5现场可编程逻辑器件(FPGA)的验证平台条件下,通过使用串并转换器来实现设计,即减少了设计复杂度,缩短了开发周期,也能最大限度的满足设计要求。  相似文献   

7.
张聪  申敏 《通信技术》2008,41(6):210-212
超宽带(Ultra Wideband,UWB)技术是近几年发展起来的一项十分有潜力的无线通信技术,正是由于其高性能,低成本的无线数据通信能力,成为实现无限个人局域网的富有竞争力的技术之一.家庭网络无线系统引入频谱利用率高效的UWB技术,可提供具有灵活性和移动性的宽带无线接入.文章依据超宽带技术的主要原理和特点,讨论了该技术在家庭网络中应用的优势和实现,使得UWB技术具备了更广泛的应用.  相似文献   

8.
李纪舟  钟建强  王瑜 《通信技术》2015,48(6):631-636
60 GHz无线通信技术以其丰富的频谱资源和高速的数据传输速率,成为目前无线通信领域的研究热点之一。首先介绍了60 GHz无线通信技术的概念内涵、特点优势和应用场景;接着重点阐述了60 GHz无线通信技术形成的产业联盟和通信标准;然后分析了60 GHz无线通信技术发展面临的问题;最后根据信息技术的发展形势,展望了60 GHz无线通信技术的发展趋势。  相似文献   

9.
Ultrawide bandwidth (UWB) wireless technology will play a key role in short-range wireless connectivity supporting very high bit rates availability, low power consumption, and location capabilities. UWB can be conveniently deployed in the design of wireless local and personal area networks, providing advanced integrated multimedia services to nomadic users within hot-spot areas. The very large bandwidth required by the UWB signals cannot be exclusively allocated; thus, UWB band overlaps with the bands allocated to many other narrow-band systems. Therefore, the assessment of the interference caused by UWB devices on already-existing systems is of primary importance to ensure coexistence and, therefore, to guarantee acceptance of UWB technology worldwide. We study the coexistence issues between an UWB-based system and universal mobile telecommunication systems, global positioning systems, DCS1800, and fixed wireless access systems and point-to-point (PP) links terminals. UWB interference is evaluated accounting for the UWB signal model, a realistic UWB master/slave system architecture with power-controlled terminals. Furthermore, we analyze the dependence of the UWB interference from the UWB signal parameters and demonstrate through computer simulation that, in all practical cases, a UWB system can coexist with the selected victim terminals without causing any dangerous interference.  相似文献   

10.
The paper provides a tutorial overview of ultrawideband (UWB) radio technology for high-speed wireless connectivity. Subsequent to establishing a historical and technological context, it describes the new impetus for UWB systems development and standardization resulting from the FCC's recent decision to permit unlicensed operation in the 3.1-10.6 GHz band subject to modified Part 15 rules and indicates the potential new applications that may result. Thereafter, the paper provides a system architect's perspectives on the various issues and challenges involved in the design of link layer subsystems. Specifically, we outline current developments in UWB system design concepts that are oriented to high-speed applications and describe some of the design tradeoffs involved.  相似文献   

11.
Ultra-wide band (UWB) communication is one of the most promising technology for high data rate networks over short-range communication. The ultra-wide bandwidth offers pulses with very short duration that provides frequency diversity and multipath resolution. Ultra-wide band (UWB) channels raise new effects in the receiver, the amplitude fading statistics being different compared to the conventional narrow band wireless channels. This review paper focuses on modeling of ultra-wide band channels, especially for simulation of personal area networks and also discusses the benefits, application potential and technical challenges in wideband communication. The concept of Orthogonal Frequency Division Multiplexing (OFDM) has recently been applied in wireless communication systems due to its high data rate transmission capability with high bandwidth efficiency and its robustness to multi-path delay. UWB OFDM communication was proposed for physical layer in the IEEE 802.15.3a standard which covers wideband communication in wireless personal area networks. Since the channel model for multicarrier UWB communication is different from that of plain ultra-wide band channel, a novel modification method in UWB channel model is proposed with specific center frequency and multipath resolution. Moreover, dynamic channel estimation is necessary before demodulation of UWB OFDM signals since the radio channel is time varying and frequency selective for wideband systems. The performance of the proposed method is statistically analyzed using LS and MMSE based channel estimation methods.  相似文献   

12.
短距离低功率无线通信接入系统   总被引:1,自引:0,他引:1  
短距离低功率无线通信接入技术主要集中在物理层和媒体访问控制(MAC)层,包括蓝牙、超宽带(UWB)和Wi-Fi等。蓝牙是链接近距离设备的电缆数据传送的辅助技术;UWB作为窄脉冲无线电技术链接众多电子设备,提供宽带无线接入的灵活性和移动性;Wi-Fi给快速接入设备和WLAN内移动设备提供无线链接,用于较长距离链接,支持一定功率的移动终端接入。短距离低功率无线通信接入系统的标准化进程非常快,辅助标准多,但目前仍以蓝牙和Wi-Fi为主。  相似文献   

13.
马惠珠  韩雅菲  叶方 《信息技术》2004,28(11):18-19,28
超宽带无线通信是利用频带非常宽、中心频率相对较低的信号进行信息传输。由于它可以用较低的发射功率进行高速传输,因而成为室内短距离无线通信的最佳选择。通过分析信号的特性及其在高斯信道中传播的特点,对Euclidean矩和比特误码率进行具体的仿真分析,最后给出了二维超宽带通信信号的设计公式。  相似文献   

14.
叶先万  游凡  崔海霞 《电讯技术》2021,61(4):517-528
为了满足人们日益增长的数据流量需求,未来无线通信系统将向更小的小区部署迁移。小蜂窝网络是下一代无线通信系统的关键技术,也是适应未来更加复杂通信环境的有效途径。首先介绍了小蜂窝网络的基本概念,论述了其主要的技术特点和独特的应用优势,分析了其在未来无线通信系统中与其他各种技术可能的融合场景并讨论了对应的特点和存在的难题;然后概述了小蜂窝网络技术发展过程中所面临的主要挑战,分析了目前主要的研究成果和解决方案;最后,结合下一代无线通信的关键技术,如大规模多输入多输出通信、毫米波通信、D2D(Device-to-Device)通信和认知无线电技术等,总结了小蜂窝网络的应用现状并分析了其市场和发展前景。  相似文献   

15.
Key technologies and new system designs for various radio over fiber (RoF) applications are proposed and demonstrated. For ultrawideband (UWB) over fiber applications, several UWB pulses generation and distribution methods are carried out. Different kinds of UWB pulses are generated based on cross-polarization modulation methods. For millimeter-wave (mm-wave) wireless applications, a 32 GHz RoF system is demonstrated with microwave frequency sextupling by optical methods. After 20 km SMF transmission, the power penalty of 2.5 Gbit/s downlink service is less than 0.15 dB. It is also suitable to apply dense wavelength division multiplexing (DWDM) technology to RoF system to support numerous base stations (BSs).  相似文献   

16.
Emerging wireless broadband networks   总被引:1,自引:0,他引:1  
The rapid evolution of mobile wireless access networks toward multimedia support with QoS provision forces the development of advanced wireless broadband systems with high reliability and high data rate. To achieve this goal, new system design concepts with increased system capacity will be required. In that context, ATM is becoming a major infrastructure, receiving a lot of attention for telecommunication systems since ATM networks can most effectively support wireless access systems. Wireless ATM systems have low transmission cost, flexible functionality, mobile ATM protocol, and radio access layer protocols. This article overviews the various wireless broadband systems studied at 5, 19.37, 40, and 60 GHz by European Union funded projects within the ACTS program. Moreover, related standardization activities and network evolution are also addressed  相似文献   

17.
崔恒荣 《电子器件》2012,35(5):509-513
60 GHz无线通信技术具有非常宽的带宽,可以应用于超高速无线数据传输,已经成为第四代无线通信的重要组成部分,学术界和工业界对此投入了持续的关注。对60 GHz频段微带波导转换结构进行了设计,结果显示在57 GHz~64 GHz通信频率范围内,插入损耗小于1 dB,回波损耗小于-15 dB,达到了实用化要求。并利用MMIC芯片完成了60 GHz毫米波通信系统T/R模块的集成设计,对QPSK通信体制下的调制和解调信号进行了分析,验证了系统的可行性。  相似文献   

18.
Photonic Generation of Ultrawideband Signals   总被引:3,自引:0,他引:3  
Ultrawideband (UWB) that is regulated by the Federal Communications Commission (FCC) for short-range high-throughput wireless communication and sensor networks with advantageous features, such as immunity to multipath fading, extremely short time duration, being carrier free, and having low duty cycle, wide bandwidth, and low power spectral density, has been a topic of interest recently. By wireless transmission, UWB communications systems can only operate in a short distance of a few meters to tens of meters. The convergence of UWB and optical fiber distribution techniques, or UWB over fiber, offers the availability of undisrupted service across different networks and eventually achieves high-data-rate access at any time and from any place. To distribute the UWB signals over the optical fiber, it is also desirable that the UWB signals can be generated in the optical domain without having extra electrical-to-optical conversion. In addition, UWB signals that are generated in the optical domain can be easily tailored to have a spectrum that meets the FCC-specified spectral mask. In this paper, techniques to generate UWB signals in the optical domain will be discussed. These techniques are divided into three categories, with the generation of UWB signals based on the following: 1) phase-modulation-to-intensity-modulation conversion; 2) a photonic microwave delay-line filter; and 3) optical spectral shaping and dispersion-induced frequency-to-time mapping. The areas for future development and the challenge of implementation of these techniques for practical applications will also be discussed.  相似文献   

19.
This paper presents an analysis and validation by advanced system simulation of compact and low-cost six-port transceivers for future wireless local area networks (WLANs) operating at millimeter-wave frequencies. To obtain realistic simulation results, a six-port model based on the measurement results of a fabricated V-band hybrid coupler, the core component, is used. A frequency-division multiplexing scheme is used by introducing four quadrature phase-shift keying (QPSK) channels in the wireless communication link. The data rate achieved is about 4 Gbit/s. The operating frequency is in the 60-64 GHz unlicensed band. Bit error rate (BER) results are presented, and a comparison is made between single-carrier and multicarrier architectures. The proposed wireless system can be considered an efficient candidate for millimeter-wave communication systems operating at quasi-optical data rates.  相似文献   

20.
超宽带无线通信技术   总被引:3,自引:0,他引:3  
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.  相似文献   

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