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1、<p><b> 中文2950字</b></p><p><b> 英文資料原文</b></p><p> INTRODUCTION OF GSM</p><p> GSM implication</p><p> The GSM full name is: Global Sys
2、tem for Mobile Communications, Chinese as the whole world two-way charges for cellular phones system, the popular name "the whole world passes", is one kind stems from Europe's mobile communication technica
3、l standard, is the second generation of mobile communication technology, its development goal is enables the world to be possible to use a mobile phone network standard together, lets the user use a handset to be able go
4、od the whole world. Our country used this </p><p> An American Famous Correspondence Company Sprint Auxiliary unit, the American person-to-person communication is using GSM to take one kind of wide band per
5、son-to-person communication service the technology. This kind of person-to-person communication service finally for Ericsson, Motorola as well as Nokia the handset which produces is establishing more than 400 base depots
6、 now. Handset includes telephone, short note beeper and intercom.</p><p> GSM and other technologies are the wireless mobile communication evolutions, wireless mobile communication including high-speed circ
7、uit exchange data, general packet radio system, based on GSM network data enlargement mode mobile communication technology as well as general mobile communication service.</p><p> GSM histories </p>
8、<p> In 1998, the goal replaced GSM for the making the third generation mobile phone (3G) the standard 3GPP start. 3GPP also accepted has maintained and continues to develop the GSM standard the work. ETSI is one o
9、f 3GPP members. In the development process, the GSM system's function obtains unceasingly richly. It can thus provide a diverse service. The short information service which first introduces by the GSM system (SMS) ha
10、s provided one kind novel, convenient, the inexpensive communication way. </p><p> In 1994, GSM has realized based on the circuit switching data traffic and the facsimile service. </p><p> In
11、1999, the WAP agreement caused the user to be possible through the handset visit Internet. After 2000, starts the commercial general grouping wireless service (GPRS) to enable the GSM system to be able to provide the dat
12、a communication by the efficiency higher packet mode. </p><p> In 2003, the EDGE technology started commercial, has provided the close 3G data communication ability. </p><p> At present, the 3
13、GPP organization is also developing the GSM standard, with the aim of using already massively deployed the GSM infrastructure, smoothly to 3G technology evolution.</p><p> GSM characteristics </p>&l
14、t;p> 1. GSM uses the direct-viewing characteristic: </p><p> The GSM system has several important characteristics: Security beats ability to be good, the network capacity is big, the handset number frui
15、tful in resources, the telephone conversation are clear, the stability not easily is disturbed, the information to be keen, the telephone conversation dead angle are few, the handset power consumption is low.</p>
16、<p> 2. GSM technical Characteristic:</p><p> 1. Frequency spectrum efficiency. Because used the highly effective modulator, the channel coding, to interweave, balanced and the speech coding technolog
17、y, enabled the system to have the high-frequency spectrum efficiency. </p><p> 2. Capacity. Because each channel transmission band width increases, causes the frequency multiplying to plant does reduces com
18、pared to the request to 9dB, therefore the GSM system's frequency multiplying pattern may reduce to 4/12 or 3/9 even is small (analogous system is 7/21); In addition the half speed rate voice code's introduction
19、and the automatic traffic distribution reduce the skip zone cut the number of times, causes the GSM system's volumetric efficiency (each megacycle each plot chan</p><p> 3. Voice quality.</p><
20、;p> In view of the fact that in digital transmission technology characteristic as well as GSM standard related space connector and voice code definition, when threshold value, the voice quality always achieves the sa
21、me level, but has nothing to do with the wireless transmission quality.</p><p> 4. Opening connection. </p><p> The GSM standard provides open connection, is not only restricted in the space c
22、onnector, moreover the publication network is direct as well as in network between equipment entity, for example A connection and Abis connection.</p><p> 5. Security.</p><p> Through the auth
23、entication, the encryption and the TMSI number's use, serves the safe purpose. The authentication uses for to confirm the user to enter the net right. The encryption uses in the space connector, by the SIM card and n
24、etwork AUC key decision. TMSI is one by the service network the temporary identification number which assigns to the user, prevents some people to track divulges its geographical position.</p><p> 6. Realiz
25、es roaming in the SIM card foundation. Roaming is the mobile communication key character, it symbolizes that the user may enter another network automatically from a network. The GSM system may provide global roaming, cer
26、tainly also needs the network operation between certain agreements, for example cost. </p><p> GSM principle </p><p> GSM is the Global System for Mobile Communication abbreviation. The meanin
27、g is the whole world mobile communication system. Divides GSM900, DCS1800 and PCS1900SAN a frequency band, the common so-called dual-frequency handset is in GSM900 and the DCS1800 frequency band cut handset. PCS1900 (PCS
28、1900 - Personal Communications System operating in the 1,900MHz band.) is other national use frequency band (for example the US). GSM900/1800 respectively is the work in the 890~960mhz/1710~1880MHz frequenc</p>&l
29、t;p> GSM900/DCS1800/PCS1900 difference: GSM900 is the initial GSM system, the MOBILE power from outputs 1W~8W, the GSM900 channel from 1~124, DCS1800 channel from 512~885; DCS1800 is the low power, highest is 1W; <
30、;/p><p> GSM frequency band: GSM900 plot radius 35km upward 880~915MHz downward 925~960MHz.</p><p> PHASE2: 890~925MHz and 935~960MHz; Channel number 1~124. </p><p> SM1800 plot rad
31、ius is 2Km (because 1800 MHz handset's low power) upward 1710~1785MHz downward 1805~1880MHz.</p><p> PHASE2: SAME; Channel number: 512~885.</p><p> For high density user,GSM1900: 1850~1910
32、MHz 1930~1990MHz upward and downward composes a frequency to be right, upward is the handset launch, machine the station receive; Downward is the base depot to the handset. For example 935~960 and 890~915 differ 45MHz, o
33、n the second channel, upward backwardness downward three time departments.</p><p> Network composition:</p><p> 1. BTS base depot: base transceiver the station base depot most important is the
34、 transceiver, the transceiver how many decision plot capacity, a transceiver can support 8 users, a plot by 3 antennas.</p><p> a) Transceiver and antenna's relations each BTS will have set of transceiv
35、ers.</p><p> b) BTS covers a plot; BTS transmits the BCH signal in the RF channel's 0 time slots. BCH helps the Mobile recognition/to seek for the network.</p><p> c) The plot handset user
36、 capacity dependence channel counts. </p><p> d) The GSM space connector data transfer rate is 13Kbps, namely the BTS receiving and dispatching pronunciation data rate is 13KB/S. </p><p> e) T
37、he BTS order handset to establish its emissive power, moves, the cut. </p><p> 2. BSC base station controller base station controller:</p><p> a) Several BTS base depots connect BSC, the base
38、depot arrangement channel disposition, the cut, and BTS connect BSC; All BSC connection to MSC, b) each BTS links BSC to use the abis connection, is the 2Mbps connection. Uses microwave link, optical fiber, ways and so o
39、n co-axial line to connect. c) Microwave link is the best connection mode choice frequently. What d) BSC links the MSC use is A e) may provide services and so on plot broadcast in BSC. </p><p> 3. MSC mobil
40、e switching center is the network core, the call setup, maintains, and the release; Links BSC and PSTN, the authentication, the call switches over, the short information, the charge and so on. When the user increases to
41、the certain amount, may increase MSC between MSC and MSC uses GMSC to link (GATEWAY). </p><p> a) Works as the call setup, MSC gets up maintains talks over the telephone and separates the telephone conversa
42、tion the function. b) Saves all user data and their related characteristic. c) Is situated between MS and PSTN, exchange correspondence data. d) MSC is the GSM network heart. Is and other GSM network, the non-GSM network
43、 company connection. e) MSC major function: The authentication, the position renew, the connection, the charge, the call to switch over, SMS. f), when the user increases</p><p> 4. TRAN------Trans coding/ra
44、te adapter unit rate adapter. </p><p> a) TRAN transforms 13KB/S the GSM speed into standard 64KB/S; TRAN takes MSC a part. </p><p> b) Trans coding also uses when downward transforms 16kbps 6
45、4kbps. </p><p> c) Trans coding in MSC \ BSC \ BTS.</p><p> 5. HLR Home location register belongs to the location register. </p><p> a) Has all user data stock in MSC to lie in H
46、LR. In HLR has the permanent user database. When b) the user sends out the call, MSC obtains the user data from HLR. Is the user core database, the majority may obtain in the SIM card data in HLR.</p><p> 6
47、. VLR visiting location register visits the location register.</p><p> a) Has in VLR all user number which activates. </p><p> b) When in other MSC user roams to new MSC, between MSC and HLR c
48、orresponds, new MSC will roam the user registers in its VLR.</p><p> c), When the handset roams, user visit area by other network cover, moreover belongs to the position network to authorize it to use the n
49、etwork which visits, its user information (will be visited from HLR by the copy to VLR location register) to temporarily store. </p><p> 7. Authentication center AUC----Authentication center </p><
50、;p> a) Is the SIM card proof procedure. b) Each SIM card as IMSI, in IMSI has Canadian password c) To have when HLR IMSI and password d) the handset corresponds, first confirms the SIM card the validity, carries on
51、the confirmation by AUC.</p><p> 8. Charge center BC---Billing center</p><p> a) BC has each user's expense condition. b) The direct company arrives at MSC, gives BC by the MSC transmissio
52、n charge information (when telephone conversation) c) BC processing according to unit cost.</p><p> 9. Operation center: OMC----operation and maintenance center. </p><p> a) Each GSM network s
53、urpasses 100 BTS compositions, each entity needs to operate and the maintenance. b) Some remote controls are necessary, the examination and long-distance enters. </p><p> 10. Short message exchange: The SMS
54、C information sends to the handset which through the short message center assigns.</p><p> a) The information transmits through SMS the information to be possible (company to arrive at SMS).</p><
55、p> b) Through the artificial terminal to transmit.</p><p> c) Short message exchange SMS.</p><p> 11. Pronunciation service center: </p><p> a) It has all pronunciation users
56、’ database;</p><p> b) It also saved the pronunciation information.</p><p><b> 譯 文</b></p><p><b> GSM簡介</b></p><p><b> 一、GSM的涵義:</b
57、></p><p> GSM全名為:Global System for Mobile Communications,中文為全球移動通訊系統(tǒng),俗稱“全球通”,是一種起源于歐洲的移動通信技術(shù)標(biāo)準(zhǔn),是第二代移動通信技術(shù),其開發(fā)目的是讓全球各地可以共同使用一個移動電話網(wǎng)絡(luò)標(biāo)準(zhǔn),讓用戶使用一部手機就能行遍全球。我國于20世紀(jì)90年代初引進采用此項技術(shù)標(biāo)準(zhǔn),此前一直是采用蜂窩模擬移動技術(shù),即第一代GSM技術(shù);目前,中
58、國移動,中國聯(lián)通的GSM網(wǎng)已經(jīng)分別為世界最大的移動通信網(wǎng)絡(luò)。GSM系統(tǒng)包括GSM900:900MHz、GSM1800:1800MHz及GSM1900:1900MHz等幾個頻段。GSM(全球移動通信系統(tǒng))是一種廣泛應(yīng)用于歐洲及世界其他地方的數(shù)字移動電話系統(tǒng)。GSM使用的是時分復(fù)用的特殊形式,并且它是目前三種數(shù)字無線電話技術(shù)(TDMA、GSM和CDMA)中使用最為廣泛的一種。GSM將資料數(shù)字化,并將數(shù)據(jù)進行壓縮,然后與其它的兩個用戶數(shù)據(jù)流一
59、起從信道發(fā)送出去,另外的兩個用戶數(shù)據(jù)流都有各自的時隙。GSM實際上是歐洲的無線電話標(biāo)準(zhǔn),據(jù)GSM MOU聯(lián)合委員會報道,GSM在全球有12億的用戶,并且用戶遍布120多個國家</p><p> 美國著名通信公司Sprint的一個輔助部門,美國個人通信正在使用GSM作為一種寬帶個人通信服務(wù)的技術(shù)。這種個人通信服務(wù)將最終為愛立信、摩托羅拉以及諾基亞現(xiàn)在正在生產(chǎn)的手持機建立400多個基站。手持機包括電話、短信尋呼機和
60、對講機。</p><p> GSM及其他技術(shù)是無線移動通信的演進,無線移動通信包括高速電路交換數(shù)據(jù)、通用無線分組系統(tǒng)、基于GSM網(wǎng)絡(luò)的數(shù)據(jù)增強型移動通信技術(shù)以及通用移動通信服務(wù)。</p><p><b> 二、GSM歷史:</b></p><p> 1998年,目標(biāo)為制訂接替GSM的第三代移動電話(3G)規(guī)范的3GPP啟動。3GPP也接受
61、了維護和繼續(xù)開發(fā)GSM規(guī)范的工作。ETSI是3GPP的成員之一。在發(fā)展的過程中,GSM系統(tǒng)的功能不斷得到豐富,從而能夠提供更多樣的服務(wù)。由GSM系統(tǒng)首先引入的短信息服務(wù)(SMS)提供了一種新穎、便捷、廉價的通訊方式。</p><p> 1994年,GSM實現(xiàn)了基于電路交換的數(shù)據(jù)業(yè)務(wù)和傳真服務(wù)。1999年,WAP協(xié)議使得用戶可以通過手機訪問互聯(lián)網(wǎng)。</p><p> 2000年后開始商用
62、的通用分組無線服務(wù)(GPRS)使得GSM系統(tǒng)能夠以效率更高的分組方式提供數(shù)據(jù)通訊。</p><p> 2003年,EDGE技術(shù)開始商用,提供了接近3G的數(shù)據(jù)通訊能力。</p><p> 目前,3GPP組織還在發(fā)展GSM標(biāo)準(zhǔn),以便利用已經(jīng)大量部署GSM基礎(chǔ)設(shè)施,平滑地向3G技術(shù)演進。</p><p><b> 三、GSM特點</b><
63、/p><p> 1.GSM使用上直觀的特點:</p><p> GSM系統(tǒng)有幾項重要特點:防盜能力佳、網(wǎng)絡(luò)容量大、手機號碼資源豐富、通話清晰、穩(wěn)定性強不易受干擾、信息靈敏、通話死角少、手機耗電量低。</p><p> 2.GSM的技術(shù)特點:</p><p> (1).頻譜效率。由于采用了高效調(diào)制器、信道編碼、交織、均衡和語音編碼技術(shù),使系
64、統(tǒng)具有高頻譜效率。</p><p> (2).容量。由于每個信道傳輸帶寬增加,使同頻復(fù)用比要求降低至9dB,故GSM系統(tǒng)的同頻復(fù)用模式可以縮小到4/12或3/9甚至更小(模擬系統(tǒng)為7/21);加上半速率話音編碼的引入和自動話務(wù)分配以減少越區(qū)切換的次數(shù),使GSM系統(tǒng)的容量效率(每兆赫每小區(qū)的信道數(shù))比TACS系統(tǒng)高3~5倍。</p><p> (3). 話音質(zhì)量。鑒于數(shù)字傳輸技術(shù)的特點以
65、及GSM規(guī)范中有關(guān)空中接口和話音編碼的定義,在門限值以上時,話音質(zhì)量總是達(dá)到相同的水平而與無線傳輸質(zhì)量無關(guān)。</p><p> (4). 開放的接口。GSM標(biāo)準(zhǔn)所提供的開放性接口,不僅限于空中接口,而且報刊網(wǎng)絡(luò)直接以及網(wǎng)絡(luò)中個設(shè)備實體之間,例如A接口和Abis接口。</p><p> (5). 安全性。通過鑒權(quán)、加密和TMSI號碼的使用,達(dá)到安全的目的。鑒權(quán)用來驗證用戶的入網(wǎng)權(quán)利。加密
66、用于空中接口,由SIM卡和網(wǎng)絡(luò)AUC的密鑰決定。TMSI是一個由業(yè)務(wù)網(wǎng)絡(luò)給用戶指定的臨時識別號,以防止有人跟蹤而泄漏其地理位置。</p><p> (6). 在SIM卡基礎(chǔ)上實現(xiàn)漫游。漫游是移動通信的重要特征,它標(biāo)志著用戶可以從一個網(wǎng)絡(luò)自動進入另一個網(wǎng)絡(luò)。GSM系統(tǒng)可以提供全球漫游,當(dāng)然也需要網(wǎng)絡(luò)運營者之間的某些協(xié)議,例如計費。</p><p><b> 四、GSM原理<
67、;/b></p><p> GSM是Global System for Mobile Communication 的縮寫。意思是全球移動通信系統(tǒng)。分GSM900、DCS1800和PCS1900三個頻段,一般的所謂的雙頻手機就是在GSM900和DCS1800頻段切換的手機。PCS1900(PCS1900 Personal Communications System operating in the 1900
68、MHz band.)則是別的一些國家使用的頻段(如美國)。 GSM900/1800分別是工作在890~960MHz/1710~1880MHz頻段的。GSM900的手機最大功率是8W(實際中移動臺沒這么大的功率,一般的手機最大功率是2W,車載臺功率較大),而DCS1800的手機的最大功率是1W。</p><p> GSM900/DCS1800/PCS1900的區(qū)別:GSM900是初始的GSM系統(tǒng),MOBILE的功
69、率從輸出1W~8W,GSM900的通道從1~124,DCS1800的通道從512~885,DCS1800是低功率的,最高是1W。</p><p> GSM的頻段:GSM900 小區(qū)半徑35Km上行880~915MHz 下行將925~960MHz</p><p> PHASE2:890~925MHz和935~960MHz;通道號1~124.</p><p> G
70、SM1800小區(qū)半徑2Km(由于1800MHz手機的低功率)上行1710~1785MHz下行1805~1880MHz。</p><p> PHASE2:SAME;通道號:512—885.為高密度的用戶.</p><p> GSM1900:1850~1910MHz 1930~1990MHz </p><p> 上行和下行組成一頻率對,上行就是手機發(fā)射、機站接收;
71、下行就是基站到手機。例如935~960和890~915相差45MHz,第二個通道上,上行落后下行三個時隙。</p><p><b> 網(wǎng)絡(luò)組成:</b></p><p> 1. BTS基站:基站首要是收發(fā)器,收發(fā)器的多少決定小區(qū)的容量,一個收發(fā)器能支持8個用戶。一個小區(qū)由3個天線,一個發(fā)射,兩個接收(分級接收)。(收發(fā)器和天線的關(guān)系)</p><
72、;p> a) 每個BTS都會有一套收發(fā)器。</p><p> b) 一個BTS覆蓋一個小區(qū),BTS發(fā)送BCH信號在RF信道的0時隙。BCH幫助Mobile識別/尋找網(wǎng)絡(luò)。</p><p> c) 小區(qū)的手機用戶容量依靠信道數(shù) </p><p> d) GSM空中接口的數(shù)據(jù)傳輸速率是13Kbps, 即BTS收發(fā)語音數(shù)據(jù)速率是13KB/S.</p&g
73、t;<p> e) 有BTS命令手機設(shè)置其發(fā)射功率、遷時、切換。</p><p> 2. BSC base station controller 基站控制器:</p><p> a) 幾個BTS基站連接一個BSC, 基站安排信道配置、切換、和BTS連接BSC; 所有的BSC連接至MSC,</p><p> b) 每個BTS連結(jié)BSC用abis接
74、口,是2Mbps的連接。使用microwave link、optical fiber、 co-axial line等方式連接.</p><p> c) Microwave link 經(jīng)常是最好的連接方式選擇。</p><p> d) BSC連結(jié)MSC使用的是A口</p><p> e) 在BSC可提供小區(qū)廣播等服務(wù)。</p><p>
75、 3. MSC mobile switching center 是網(wǎng)絡(luò)的核心,呼叫建立、保持、和釋放;鏈接BSC和PSTN、 認(rèn)證、呼叫轉(zhuǎn)接、短信息、收費等。當(dāng)用戶增加到一定數(shù)量時,可增加MSC;MSC與MSC之間使用GMSC連結(jié)(GATEWAY)</p><p> a) 當(dāng)呼叫建立時,MSC起到保持通話和斷開通話的功能。</p><p> b) 存儲所有的用戶數(shù)據(jù)和它們的相關(guān)特征。&
76、lt;/p><p> c) 介于MS和PSTN之間,交換通信數(shù)據(jù).</p><p> d) MSC是GSM 網(wǎng)絡(luò)的心臟。是與別的GSM 網(wǎng)絡(luò)、非GSM網(wǎng)絡(luò)的連接口。</p><p> e) MSC主要功能:認(rèn)證、位置更新、連接、收費、呼叫轉(zhuǎn)接、SMS。</p><p> f) 當(dāng)用戶增加時,超過一個MSC的容量,就需要多一個MSC,增加一
77、倍的用戶</p><p> 4. TRAN-----Trans coding/rate adapter unit 速率適配器。</p><p> a) TRAN轉(zhuǎn)換13KB/S的GSM速率為標(biāo)準(zhǔn)的64KB/S; TRAN作為MSC的一部分。</p><p> b) Trans coding 也使用在下行時,將64Kbps轉(zhuǎn)換成16Kbps.</p>
78、<p> c) Trans coding在MSC\BSC\BTS中。</p><p> 5. HLR Home location register歸屬位置寄存器。</p><p> a) 在MSC中有所有的用戶數(shù)據(jù)庫存在于HLR。HLR中有永久用戶數(shù)據(jù)庫。</p><p> b) 用戶發(fā)出呼叫時,MSC從HLR之中獲得用戶數(shù)據(jù)。是用戶核心數(shù)據(jù)庫
79、,大部分在SIM卡中的數(shù)據(jù)都可以在HLR中獲得。</p><p> 6. VLR visiting location register訪問位置寄存器。</p><p> a) 在VLR中有被激活的所有的用戶號碼。</p><p> b) 當(dāng)別的MSC中的用戶漫游到新的MSC時,MSC和HLR之間通信,新的MSC就將漫游的用戶注冊到它的VLR中。</p&g
80、t;<p> c) 當(dāng)手機漫游時,用戶訪問區(qū)被別的網(wǎng)絡(luò)覆蓋,而且歸屬位置網(wǎng)絡(luò)批準(zhǔn)它使用被訪問的網(wǎng)絡(luò),它的用戶信息將從HLR被拷貝到VLR(訪問位置寄存器)中暫存。</p><p> 7. 鑒權(quán)中心AUC----Authentication center</p><p> a) 是SIM 卡的驗證過程。</p><p> b) 每個SIM卡有一個
81、IMSI, 在IMSI有加密碼</p><p> c) 在HLR中有IMSI和密碼</p><p> d) 手機通信時,首先驗證SIM 卡的合法性,由AUC 進行驗證。</p><p> 8. 收費中心BC---Billing center</p><p> a) BC產(chǎn)生每一個用戶的費用狀況.</p><p>
82、; b) 直接連到MSC,由MSC發(fā)送收費信息給BC(通話時)</p><p> c) BC處理按單位計費。</p><p> 9. 操作運營中心:OMC----operation and maintenance center.</p><p> a) 每個GSM網(wǎng)絡(luò)超過100個BTS組成,每一個實體需要操作和維護。</p><p>
83、 b) 一些遠(yuǎn)程操縱是必要的,檢測和遠(yuǎn)程進入。</p><p> 10. 短信中心:SMSC信息通過短信息中心發(fā)到指定的手機。</p><p> a) 信息通過SMSC傳輸</p><p> b) 信息可通過人工終端(連到SMSC)發(fā)送。</p><p> c) 短信中心SMS CENTER---MSC/VLR----BSC----
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