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lte

lte(LongTermEvolution,長期演進)是由3GPP(The3rdGenerationPartnershipProject,第三代合作伙伴計劃)組織制定的UMTS(UniversalMobileTelecommunicationsSystem,通用移動通信系統)技術標準的長期演進,于2004年12月在3GPP多倫多會議上正式立項并啟動。lte系統引入了OFDM(OrthogonalFrequencyDivisionMultiplexing,正交頻分復用)和MIMO(Multi-Input&Multi-Output,多輸入多輸出)等關鍵技術,顯著增加了頻譜效率和數據傳輸速率(20M帶寬2X2MIMO在64QAM情況下,理論下行最大傳輸速率為201Mbps,除去信令開銷后大概為150Mbps,但根據實際組網以及終端能力限制,一般認為下行峰值速率為100Mbps,上行為50Mbps),并支持多種帶寬分配:1.4MHz,3MHz,5MHz,10MHz,15MHz和20MHz等,且支持全球主流2G/3G頻段和一些新增頻段,因而頻譜分配更加靈活,系統容量和覆蓋也顯著提升。[1]
  • FDD+lte基站收發模塊射頻性能測試與調試.

    隨著現代移動通信系統在全球商用化的快速推進與蓬勃發展,以及通信系統日益增長的高速多媒體數據業務需求,新一代移動通信系統需要更多更先進的技術來實現更高的傳輸速率和系統容量,目前世界各國已將研究重點轉入第四代移動通信系統的研究和開發。第三代合作伙伴計劃(3GPP)通用移動通信系統技術的長期演進(lte)作為第四代移動通信系統的主要研究技術方向,具有高速率、高系統容量、良好兼容性、應用更多先進技術等特點。基站收發機在移動通信系統中特別是lte基站中起著十分重要的作用,也是基站重要功能組成部分之一。收發機的射頻性能直接決定了基站通信質量以及能否正常運行,在正常使用過程中,基站與其他通信設備之間是否互相影響與相互間是否造成干擾也是收發機射頻應用部分重點關注的問題之一。本課題將通過完成基站射頻收發機項目的研發和應用,包括頻分雙工(FDD)lte基站射頻系統測試與調試,對射頻收發模塊關鍵技術指標與電路進行研究,對收發鏈路重要參數進行說明,并分析測試原理與意義,介紹測試系統與平臺、測試方法和技術要點。在本文研究過程中,主要包括三個方面的工作:1)介紹FDD lte基站收發模塊系統的基本結構,并對其關鍵技術進行研究,比如收發射頻鏈路,數字預失真等。

    標簽: fdd lte 基站

    上傳時間: 2022-06-20

    上傳用戶:fliang

  • 4G移動通信技術權威指南:ltelte-Advanced.4G lte.lte

    PrefaceDuring the past years, there has been a quickly rising interest in radio access technologies for providingmobile as well as nomadic and fixed services for voice, video, and data. The difference indesign, implementation, and use between telecom and datacom technologies is also becoming moreblurred. One example is cellular technologies from the telecom world being used for broadband dataand wireless LAN from the datacom world being used for voice-over IP.Today, the most widespread radio access technology for mobile communication is digital cellular,with the number of users passing 5 billion by 2010, which is more than half of the world’s population.It has emerged from early deployments of an expensive voice service for a few car-borne users,to today’s widespread use of mobile-communication devices that provide a range of mobile servicesand often include camera, MP3 player, and PDA functions. With this widespread use and increasinginterest in mobile communication, a continuing evolution ahead is foreseen.This book describes lte, developed in 3GPP (Third Generation Partnership Project) and providingtrue 4G broadband mobile access, starting from the first version in release 8 and through the continuingevolution to release 10, the latest version of lte. Release 10, also known as lte-Advanced,is of particular interest as it is the major technology approved by the ITU as fulfilling the IMTAdvancedrequirements. The description in this book is based on lte release 10 and thus provides acomplete description of the lte-Advanced radio access from the bottom up.Chapter 1 gives the background to lte and its evolution, looking also at the different standardsbodies and organizations involved in the process of defining 4G. It also gives a discussion of the reasonsand driving forces behind the evolution.Chapters 2–6 provide a deeper insight into some of the technologies that are part of lte and itsevolution. Because of its generic nature, these chapters can be used as a background not only for lteas described in this book, but also for readers who want to understand the technology behind othersystems, such as WCDMA/HSPA, WiMAX, and CDMA2000.Chapters 7–17 constitute the main part of the book. As a start, an introductory technical overviewof lte is given, where the most important technology components are introduced based onthe generic technologies described in previous chapters. The following chapters provide a detaileddescription of the protocol structure, the downlink and uplink transmission schemes, and the associatedmechanisms for scheduling, retransmission and interference handling. Broadcast operation andrelaying are also described. This is followed by a discussion of the spectrum flexibility and the associated

    標簽: 4g 移動通信

    上傳時間: 2022-07-08

    上傳用戶:

  • 中興全套lte培訓資料之三

    分享一下中興全套lte培訓資料,希望對大家有所幫助第一部分鏈接:http://dl.21ic.com/download/lte-299458.html 第二部分鏈接:http://dl.21ic.com/download/lte-299459.html 第三部分鏈接:http://dl.21ic.com/download/lte-299460.html 

    標簽: 中興 lte

    上傳時間: 2022-07-18

    上傳用戶:

  • 中興全套lte培訓資料之二

    分享一下中興全套lte培訓資料,希望對大家有所幫助第一部分鏈接:http://dl.21ic.com/download/lte-299458.html 第二部分鏈接:http://dl.21ic.com/download/lte-299459.html 第三部分鏈接:http://dl.21ic.com/download/lte-299460.html 

    標簽: 中興 lte

    上傳時間: 2022-07-18

    上傳用戶:

  • 中興全套lte培訓資料之一

    分享一下中興全套lte培訓資料,希望對大家有所幫助第一部分截圖:第二部分鏈接:http://dl.21ic.com/download/lte-299459.html 第三部分鏈接:http://dl.21ic.com/download/lte-299460.html 

    標簽: 中興 lte

    上傳時間: 2022-07-18

    上傳用戶:XuVshu

  • 數字預失真系統反饋通道增益平坦度的補償

    針對數字預失真系統對反饋鏈路平坦度的要求,提出一種在不斷開模擬鏈路的前提下,采用單音測量WCDMA&lte混模基站射頻拉遠單元反饋鏈路的增益平坦度,并采用最小二乘法,分別擬合射頻、本振和中頻的增益的方法。采用MATLAB工具產生濾波器系數,在基本不增加復雜度的基礎上,通過DPD軟件離線補償中頻的增益不平坦度。實際應用取得良好的補償效果。

    標簽: 數字預失真 反饋 增益

    上傳時間: 2013-10-18

    上傳用戶:haohaoxuexi

  • TI KeyStone架構支持L2及傳輸處理

    無線技術的持續演進發展、全球無線用戶的激增,以及市場對更強大數據承載能力的需求,全面催生了各種新標準的不斷涌現,如寬帶碼分多址 - 高速分組接入 (WCDMA-HSPA)、WCDMA-HSPA+ 以及長期演進技術 (lte) 等。基于無線服務網絡的數據使用呈指數級增長,從而進一步推動了異構網絡的出現 —— 支持宏蜂窩基站和小型蜂窩基站的分層網絡部署方案。

    標簽: KeyStone TI 架構 傳輸處理

    上傳時間: 2013-11-25

    上傳用戶:cc1915

  • 無線和RF解決方案

    Linear Technology offers some of the highest performance RF and signal chain solutions for wireless and cellularinfrastructure. These products support worldwide standards including, lte, WiMAX, GSM,W-CDMA, TD-SCDMA,CDMA, and CDMA2000. Other wireless systems include broadband microwave data links, secure communications,satellite receivers, broadband wireless access, wireless broadcast systems, RFID readers and cable infrastructure

    標簽: 無線 方案

    上傳時間: 2013-11-04

    上傳用戶:kiklkook

  • lte_A系統中繼技術的研究

    中繼技術作為lte-Advanced 系統的關鍵候選技術之一,將為小區帶來更大的覆蓋范圍和更高的系統容量,以及更廉價的網絡建設成本。對當前lte-Advanced 系統中的中繼技術進行全面系統的介紹。主要對中繼的分類,資源復用方式和引入中繼后的干擾情況做重點闡述。

    標簽: lte_A 中繼技術

    上傳時間: 2013-12-20

    上傳用戶:kr770906

  • 710MHz lte天線的去耦合分析

    由于移動終端上空間有限, 多個天線間存在較大耦合, 天線的輻射效率和通信容量會降低。為了解決這一問題, 從S 參數的角度推導出了天線的正交輻射模式, 提出了通過加入180

    標簽: 710 MHz lte 天線

    上傳時間: 2013-10-23

    上傳用戶:laomv123

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