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LTE

LTE(LongTermEvolution,長(zhǎng)期演進(jìn))是由3GPP(The3rdGenerationPartnershipProject,第三代合作伙伴計(jì)劃)組織制定的UMTS(UniversalMobileTelecommunicationsSystem,通用移動(dòng)通信系統(tǒng))技術(shù)標(biāo)準(zhǔn)的長(zhǎng)期演進(jìn),于2004年12月在3GPP多倫多會(huì)議上正式立項(xiàng)并啟動(dòng)。LTE系統(tǒng)引入了OFDM(OrthogonalFrequencyDivisionMultiplexing,正交頻分復(fù)用)和MIMO(Multi-Input&Multi-Output,多輸入多輸出)等關(guān)鍵技術(shù),顯著增加了頻譜效率和數(shù)據(jù)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(kāi)銷(xiāo)后大概為150Mbps,但根據(jù)實(shí)際組網(wǎng)以及終端能力限制,一般認(rèn)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(tǒng)容量和覆蓋也顯著提升。[1]
  • FDD+LTE基站收發(fā)模塊射頻性能測(cè)試與調(diào)試.

    隨著現(xiàn)代移動(dòng)通信系統(tǒng)在全球商用化的快速推進(jìn)與蓬勃發(fā)展,以及通信系統(tǒng)日益增長(zhǎng)的高速多媒體數(shù)據(jù)業(yè)務(wù)需求,新一代移動(dòng)通信系統(tǒng)需要更多更先進(jìn)的技術(shù)來(lái)實(shí)現(xiàn)更高的傳輸速率和系統(tǒng)容量,目前世界各國(guó)已將研究重點(diǎn)轉(zhuǎn)入第四代移動(dòng)通信系統(tǒng)的研究和開(kāi)發(fā)。第三代合作伙伴計(jì)劃(3GPP)通用移動(dòng)通信系統(tǒng)技術(shù)的長(zhǎng)期演進(jìn)(LTE)作為第四代移動(dòng)通信系統(tǒng)的主要研究技術(shù)方向,具有高速率、高系統(tǒng)容量、良好兼容性、應(yīng)用更多先進(jìn)技術(shù)等特點(diǎn)?;臼瞻l(fā)機(jī)在移動(dòng)通信系統(tǒng)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(fā)機(jī)的射頻性能直接決定了基站通信質(zhì)量以及能否正常運(yùn)行,在正常使用過(guò)程中,基站與其他通信設(shè)備之間是否互相影響與相互間是否造成干擾也是收發(fā)機(jī)射頻應(yīng)用部分重點(diǎn)關(guān)注的問(wèn)題之一。本課題將通過(guò)完成基站射頻收發(fā)機(jī)項(xiàng)目的研發(fā)和應(yīng)用,包括頻分雙工(FDD)LTE基站射頻系統(tǒng)測(cè)試與調(diào)試,對(duì)射頻收發(fā)模塊關(guān)鍵技術(shù)指標(biāo)與電路進(jìn)行研究,對(duì)收發(fā)鏈路重要參數(shù)進(jìn)行說(shuō)明,并分析測(cè)試原理與意義,介紹測(cè)試系統(tǒng)與平臺(tái)、測(cè)試方法和技術(shù)要點(diǎn)。在本文研究過(guò)程中,主要包括三個(gè)方面的工作:1)介紹FDD LTE基站收發(fā)模塊系統(tǒng)的基本結(jié)構(gòu),并對(duì)其關(guān)鍵技術(shù)進(jìn)行研究,比如收發(fā)射頻鏈路,數(shù)字預(yù)失真等。

    標(biāo)簽: fdd LTE 基站

    上傳時(shí)間: 2022-06-20

    上傳用戶:fliang

  • 4G移動(dòng)通信技術(shù)權(quán)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(biāo)簽: 4g 移動(dòng)通信

    上傳時(shí)間: 2022-07-08

    上傳用戶:

  • 中興全套LTE培訓(xùn)資料之三

    分享一下中興全套LTE培訓(xùn)資料,希望對(duì)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(biāo)簽: 中興 LTE

    上傳時(shí)間: 2022-07-18

    上傳用戶:

  • 中興全套LTE培訓(xùn)資料之二

    分享一下中興全套LTE培訓(xùn)資料,希望對(duì)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(biāo)簽: 中興 LTE

    上傳時(shí)間: 2022-07-18

    上傳用戶:

  • 中興全套LTE培訓(xùn)資料之一

    分享一下中興全套LTE培訓(xùn)資料,希望對(duì)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(biāo)簽: 中興 LTE

    上傳時(shí)間: 2022-07-18

    上傳用戶:XuVshu

  • 數(shù)字預(yù)失真系統(tǒng)反饋通道增益平坦度的補(bǔ)償

    針對(duì)數(shù)字預(yù)失真系統(tǒng)對(duì)反饋鏈路平坦度的要求,提出一種在不斷開(kāi)模擬鏈路的前提下,采用單音測(cè)量WCDMA&LTE混?;旧漕l拉遠(yuǎn)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(chǎn)生濾波器系數(shù),在基本不增加復(fù)雜度的基礎(chǔ)上,通過(guò)DPD軟件離線補(bǔ)償中頻的增益不平坦度。實(shí)際應(yīng)用取得良好的補(bǔ)償效果。

    標(biāo)簽: 數(shù)字預(yù)失真 反饋 增益

    上傳時(shí)間: 2013-10-18

    上傳用戶:haohaoxuexi

  • TI KeyStone架構(gòu)支持L2及傳輸處理

    無(wú)線技術(shù)的持續(xù)演進(jìn)發(fā)展、全球無(wú)線用戶的激增,以及市場(chǎng)對(duì)更強(qiáng)大數(shù)據(jù)承載能力的需求,全面催生了各種新標(biāo)準(zhǔn)的不斷涌現(xiàn),如寬帶碼分多址 - 高速分組接入 (WCDMA-HSPA)、WCDMA-HSPA+ 以及長(zhǎng)期演進(jìn)技術(shù) (LTE) 等?;跓o(wú)線服務(wù)網(wǎng)絡(luò)的數(shù)據(jù)使用呈指數(shù)級(jí)增長(zhǎng),從而進(jìn)一步推動(dòng)了異構(gòu)網(wǎng)絡(luò)的出現(xiàn) —— 支持宏蜂窩基站和小型蜂窩基站的分層網(wǎng)絡(luò)部署方案。

    標(biāo)簽: KeyStone TI 架構(gòu) 傳輸處理

    上傳時(shí)間: 2013-11-25

    上傳用戶:cc1915

  • 無(wú)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(biāo)簽: 無(wú)線 方案

    上傳時(shí)間: 2013-11-04

    上傳用戶:kiklkook

  • LTE_A系統(tǒng)中繼技術(shù)的研究

    中繼技術(shù)作為LTE-Advanced 系統(tǒng)的關(guān)鍵候選技術(shù)之一,將為小區(qū)帶來(lái)更大的覆蓋范圍和更高的系統(tǒng)容量,以及更廉價(jià)的網(wǎng)絡(luò)建設(shè)成本。對(duì)當(dāng)前LTE-Advanced 系統(tǒng)中的中繼技術(shù)進(jìn)行全面系統(tǒng)的介紹。主要對(duì)中繼的分類(lèi),資源復(fù)用方式和引入中繼后的干擾情況做重點(diǎn)闡述。

    標(biāo)簽: LTE_A 中繼技術(shù)

    上傳時(shí)間: 2013-12-20

    上傳用戶:kr770906

  • 710MHz LTE天線的去耦合分析

    由于移動(dòng)終端上空間有限, 多個(gè)天線間存在較大耦合, 天線的輻射效率和通信容量會(huì)降低。為了解決這一問(wèn)題, 從S 參數(shù)的角度推導(dǎo)出了天線的正交輻射模式, 提出了通過(guò)加入180

    標(biāo)簽: 710 MHz LTE 天線

    上傳時(shí)間: 2013-10-23

    上傳用戶:laomv123

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