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umts

通用移動通信系統,簡稱umts(UniversalMobileTelecommunicationsSystem),umts作為一個完整的3G移動通信技術標準,umts并不僅限于定義空中接口。除WCDMA作為首選空中接口技術獲得不斷完善外,umts還相繼引入了TD-SCDMA和HSDPA技術。
  • Indoor Radio Planning A Practical Guide for GSM

    This book is intended for the RF planners, to serve as a practical tool in their daily work designing indoor radio distribution systems. It is not a complete book about all the deep aspects and corners of GSM, DCS, umts and HSPA networks, or all the core network systems. It is dedicated to the last 10–70 m of the network, the indoor air interface between the mobile user and the indoor mobile network.

    標簽: Practical Planning Indoor Guide Radio GSM for

    上傳時間: 2020-05-27

    上傳用戶:shancjb

  • Radio+Resource+Management+Strategies

    It is more than a decade since GSM was first commercially available. After some unexpected delay, it seems that finally umts is here to stay as a 3G system standardised by 3GPP, at least for another ten years. umts will enable multi-service, multi-rate and flexible IP native-based mobile technologies to be used in wide area scenarios and also pave the way for a smooth transition from circuit switched voice networks to mobile packet services.

    標簽: Management Strategies Resource Radio

    上傳時間: 2020-06-01

    上傳用戶:shancjb

  • Reconfigurable+Mobile+Radio+Systems

    Digital mobile wireless communication and the Internet have undergone a fantastic growth in the last few years and, despite originating from two different worlds, they are converging. This convergence corresponds to the evolution of mobile systems towards the highest broadband data transmissions (GSM, EDGE/GPRS, umts then HSDPA), while the computing world gets equipped with wireless technologies such as Wi-Fi or Wi-Max.

    標簽: Reconfigurable Systems Mobile Radio

    上傳時間: 2020-06-01

    上傳用戶:shancjb

  • Time-Varying Channels

    Wireless communications has become a field of enormous scientific and economic interest. Recent success stories include 2G and 3G cellular voice and data services (e.g., GSM and umts), wireless local area networks (WiFi/IEEE 802.11x), wireless broadband access (WiMAX/IEEE 802.16x), and digital broadcast systems (DVB, DAB, DRM). On the physical layer side, traditional designs typically assume that the radio channel remains constant for the duration of a data block. However, researchers and system designers are increasingly shifting their attention to channels that may vary within a block. In addition to time dispersion caused by multipath propagation, these rapidly time-varying channels feature frequency dispersion resulting from the Doppler effect. They are, thus, often referred to as being “doubly dispersive.”

    標簽: Time-Varying Channels

    上傳時間: 2020-06-01

    上傳用戶:shancjb

  • umts+Network+Planning

    The continuing explosive growth in mobile communication is demanding more spectrally efficient radio access technologies than the prevalent second generation (2G) systems such as GSM to handle just the voice traffic. We are already witnessing high levels of mobile penetration exceeding 70% in some countries. It is anticipated that by 2010 more than half of all communications will be carried out by mobile cellular networks. On the other hand, the information revolution and changing life habits are bringing the requirement of commu- nicating on a multimedia level to the mobile environment. But the data handling capabilities and flexibility of the 2G cellular systems are limited.

    標簽: Planning Network umts

    上傳時間: 2020-06-01

    上傳用戶:shancjb

  • WCDMA for umts HSPA Evolution and LTE

    Second-generation telecommunication systems, such as the Global System for Mobile Communications (GSM), enabled voice traffic to go wireless: the number of mobile phones exceeds the number of landline phones and the mobile phone penetration is approaching 100% in several markets. The data-handling capabilities of second-generation systems are limited, however, and third-generation systems are needed to provide the high bit-rate services that enable high-quality images and video to be transmitted and received, and to provide access to the Web with higher data rates.

    標簽: Evolution WCDMA umts HSPA LTE for and

    上傳時間: 2020-06-01

    上傳用戶:shancjb

  • Wireless+Communication+Circuits+and+Systems

    This book is concerned with integrated circuits and systems for wireless and mobile communications. Circuit techniques and implementation of reconfigurable low-voltage and low-power single-chip CMOS transceivers for multiband and multi- mode universal wireless communications are the focus of the book. Applications encompass both long-range mobile cellular communications (GSM and umts) and short-range wireless LANs (IEEE802.11 and Bluetooth). Recent advances in research into transceiver architecture, RF frontend, analogue baseband, RF CAD and automatic testing are reported. 

    標簽: Communication Wireless Circuits Systems and

    上傳時間: 2020-06-01

    上傳用戶:shancjb

  • WLANs+WPANs+towards+4G+Wireless

    This book paves the path toward fourth generation (4G) mobile communica- tion by introducing mobility in heterogeneous IP networks with both third generation (3G) and wireless local area networks (WLANs), which is seen as one of the central issues in the becoming 4G of telecommunications networks and systems. This book presents a thorough overview of 3G networks and standards and discusses interworking and handover mechanisms between WLANs and the Universal Mobile Telecommunication System (umts).

    標簽: Wireless towards WLANs WPANs 4G

    上傳時間: 2020-06-01

    上傳用戶:shancjb

  • 窄帶物聯網(NB-IoT)

    窄帶物聯網(NB-IoT)窄帶物聯網(Narrow Band Internet of Things, NB-IoT)成為萬物互聯網絡的一個重要分支。NB-IoT構建于蜂窩網絡,只消耗大約180kHz的帶寬,可直接部署于GSM網絡、umts網絡或LTE網絡,以降低部署成本、實現平滑升級。 NB-IoT是IoT領域一個新興的技術,支持低功耗設備在廣域網的蜂窩數據連接,也被叫作低功耗廣域網(LPWAN)。NB-IoT支持待機時間長、對網絡連接要求較高設備的高效連接。據說NB-IoT設備電池壽命可以提高至少10年,同時還能提供非常全面的室內蜂窩數據連接覆蓋。2017年7月13日,ofo小黃車與中國電信、華為共同宣布,三家聯合研發的NB-IoT(Narrow Band Internet of Things,窄帶物聯網)“物聯網智能鎖”全面啟動商用。 [9]  據了解,在此次三方合作中,ofo負責智能鎖設備開發,中國電信負責提供NB-IoT物聯網的商用網絡、華為負責芯片方面的服務。此前ofo已經開始使用這款物聯網智能鎖,而此次將啟動全面的商用。

    標簽: NB-IOT

    上傳時間: 2022-04-19

    上傳用戶:

  • 《大話核心網-陳學梁》高清文字版

    《大話核心網-陳學梁》,學習核心網的好書。本書根據核心網演進的脈絡,采用淺顯易懂的類比方式,描述了程控交換、七號信令、NGN網絡、SIP協議、IMS網絡、umts PS核心網、LTE EPC核心網、SDN網絡等系統,并根據多年的技術理解,論述了核心網演進的基本規律,向讀者描述了一張完整的核心網發展圖。通過回顧核心網的歷史,可以更深入地理解作者對核心網發展的一些思考和結論。本書不是關于核心網的第一本讀物,但將會是核心網領域的第一幅技術地圖。本書立足于通信從業人員,用淺顯易懂的表述方式,全新地闡述了核心網的方方面面,適合高校教師、相關專業的學生、運營商、設備商,以及通信網絡規劃人員閱讀與參考。 未經許可,不得以任何方式復制或抄襲本書之部分或全部內容。

    標簽: 核心網

    上傳時間: 2022-06-17

    上傳用戶:

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