第三代移動通信系統(tǒng)(3G)的標(biāo)準(zhǔn)及其業(yè)務(wù)分析

Analysis of 3G standards and services

第三代移動通信系統(tǒng)(3G)的標(biāo)準(zhǔn)及其業(yè)務(wù)分析

北方交通大學(xué) 運(yùn)輸自動化與通信實(shí)驗(yàn)室 趙曉紅

北方交通大學(xué)現(xiàn)代通信研究所 楊濤


Abstract: Wireless mobile communication system has developed from analog system to current digital system. With big increase of demand on communication business type and quantity, 2G mobile communication system with business modes limited to voice and low rate data can not satisfy the demand any more, large-capacity, high-speed, full-scale 3G comes out. This paper mainly introduces standardization of 3G and also makes analysis of its main business modes.
Key words: 3G, RTT, wireless access network

摘要：無線移動通信系統(tǒng)已經(jīng)由第一代模擬系統(tǒng)發(fā)展到了現(xiàn)在的第二代數(shù)字系統(tǒng)，隨著對通
信業(yè)務(wù)種類和數(shù)量需求的劇增，業(yè)務(wù)類型主要限于語音和低速數(shù)據(jù)的第二代移動通信系統(tǒng)已
不能滿足需要，大容量、高速率、全方位的第三代移動通信系統(tǒng)（3G）應(yīng)運(yùn)而生。本文主要
介紹了3G的標(biāo)準(zhǔn)化過程，并對其主要業(yè)務(wù)類型進(jìn)行了分析。
關(guān)鍵字：第三代移動通信系統(tǒng) 無線傳輸提案(RTT) 無線接入網(wǎng)



一、3G介紹
經(jīng)過六七十年的發(fā)展,通信系統(tǒng),已經(jīng)從最初的專用網(wǎng)發(fā)展到現(xiàn)在可以覆蓋全球大部分地區(qū)的
公用網(wǎng)；已經(jīng)從最初的大區(qū)制網(wǎng)絡(luò)結(jié)構(gòu)發(fā)展到現(xiàn)在的蜂窩小區(qū)網(wǎng)絡(luò)結(jié)構(gòu)；已經(jīng)從最初的模擬
網(wǎng)絡(luò)發(fā)展到現(xiàn)在的數(shù)字網(wǎng)絡(luò)公用網(wǎng)。通信系統(tǒng)經(jīng)過第一、二代的發(fā)展,已經(jīng)進(jìn)入了向第三代轉(zhuǎn)
化的過程。隨著通信業(yè)務(wù)的迅猛發(fā)展,通信量的激增,現(xiàn)有的第二代移動通信系統(tǒng)在支持全球
漫游、頻譜利用率以及數(shù)據(jù)業(yè)務(wù)方面都表現(xiàn)出了一定的不足,盡管GSM的Phase 2＋支持較高的
數(shù)據(jù)傳輸速率,但這只是對第二代移動通信技術(shù)的補(bǔ)綴,并且以犧牲其他用戶的利益為代價,對
系統(tǒng)用戶并不有利。第三代移動通信技術(shù)（3G）應(yīng)運(yùn)而生,3G使通信世界朝著媒體集中、行業(yè)
合并的方向邁進(jìn),互聯(lián)網(wǎng)、IP技術(shù)和移動通信即將融為一體。第三代移動互聯(lián)網(wǎng)技術(shù)的飛速發(fā)
展必然帶來各方面重大的變革：

◆人們將不只是用耳朵聽而更多的用眼睛看,眼睛將成為人們從3G中獲取信息與知識的主要工
具。

◆3G中數(shù)據(jù)（“非語音”）業(yè)務(wù)將與傳統(tǒng)的語音業(yè)務(wù)截然不同。

◆移動通信在容量上將與固定通信相當(dāng),很多人將只擁有一部移動電話。

◆移動電話將成為人們生活中必不缺少的一部分。它將成為引導(dǎo)人們生活的核心。它可以實(shí)
現(xiàn)人們?nèi)魏蔚攸c(diǎn)、任何時間與任何人進(jìn)行通信的夢想。

◆3G是建立在碼分多址(CDMA)的基礎(chǔ)之上,這與2G中廣泛采用的時分多址(TDMA)不同。

◆美國、日本和歐洲的移動通信商家都有自己的技術(shù),現(xiàn)在統(tǒng)一為一個標(biāo)準(zhǔn),各自獨(dú)立的無線
發(fā)展道路及歐洲無線的領(lǐng)導(dǎo)地位因而受到了挑戰(zhàn)。

二、3G的標(biāo)準(zhǔn)

2.1 3G的標(biāo)準(zhǔn)化進(jìn)程

早在1985年,國際電信聯(lián)盟（ITU）就提出了第三代移動通信的概念,當(dāng)時稱為未來公用陸地移
動通信系統(tǒng)（FPLMTS）,1996年改為IMT-2000。由于移動通信在未來的信息產(chǎn)業(yè)中的重要作用,
各國的政府部門、電信運(yùn)營商及制造商均積極的參與有關(guān)第三代移動通信標(biāo)準(zhǔn)的制定工作。
截至1998年9月,16個無線傳輸技術(shù)（RTT）的提案被提交：除6個衛(wèi)星接口方案外,地面無線接
口方案有10個,主要分為兩大類：CDMA與TDMA,其中CDMA占據(jù)主導(dǎo)地位。這幾項(xiàng)技術(shù)涵蓋了歐
洲的W－CDMA、美國的cdma2000和我國的TD－SCDMA等制式,焦點(diǎn)主要集中在W－CDMA和cdma2000上。

2.2 3GPP

1998年10月,第三代伙伴計(jì)劃（3GPP）出臺,該標(biāo)準(zhǔn)化組織由歐洲的ETSI、中國的CWTS、日本
ARIB、韓國TTA和美國的T1等組成,宗旨是制定以GSM為核心網(wǎng),UTRA為無線接口的標(biāo)準(zhǔn)。1999
年1月,3GPP2正式成立,該組織包括美國的TIA、中國的CWTS、日本ARIB、韓國TTA等,宗旨是制
定以ANSI/IS-41為核心網(wǎng),cdma2000、WUC136 為無線接口的標(biāo)準(zhǔn)。世界上各大標(biāo)準(zhǔn)制定組織
間空前的合作大大加速了第三代移動通信系統(tǒng)的標(biāo)準(zhǔn)化進(jìn)程。1999年上半年, 全球IMT-2000
標(biāo)準(zhǔn)取得很大進(jìn)展,該標(biāo)準(zhǔn)能夠滿足不同技術(shù)實(shí)體棗GSM、CDMA及TDMA在政治和商業(yè)上的要求。

2.3 空中接口模式

第三代移動通信網(wǎng)的IMT-2000標(biāo)準(zhǔn)是一種基于CDMA的標(biāo)準(zhǔn),該標(biāo)準(zhǔn)包含三種任意的操作模式,
每一種模式都能通過GSM MAP和IS-41網(wǎng)絡(luò)結(jié)構(gòu)進(jìn)行工作。這三種模式是：
三種操作模式,一種針對歐洲和亞洲。一種針對日本,另一種針對美國,與原有的2G的模式有
一些相似,主要的變動是日本已加入了歐洲的GSM共同體,采用了WCDMA。
事實(shí)上嚴(yán)格得講,如果把DECT (IMT FT) 和 EDGE (IMT SC 或 IWC 136)包括在內(nèi)的話,最終
的IMT-2000的ITU提案包括五種地面無線接入標(biāo)準(zhǔn)。
三種無線接入模式中主要的核心網(wǎng)絡(luò)標(biāo)準(zhǔn)有兩種（現(xiàn)有）：GSM MAP和TIA IS-41（通信聯(lián)盟,
英國的標(biāo)準(zhǔn)制定組織）。在移動通信網(wǎng)中,核心網(wǎng)是無線接入網(wǎng)所要連接的網(wǎng)絡(luò)設(shè)備。無線接
入網(wǎng)是移動通信網(wǎng)的一部分,用來處理用戶接入包括無線基站和其它節(jié)點(diǎn)的接入問題。

2.4 3G的數(shù)據(jù)傳輸速率

國際電信聯(lián)盟（ITU）已經(jīng)提出了IMT-2000標(biāo)準(zhǔn)必須支持的最低的數(shù)據(jù)傳輸速率。這要根據(jù)正
在進(jìn)行的呼叫的移動性來定義。即3G所能支持的數(shù)據(jù)傳輸速率取決于呼叫所發(fā)生的環(huán)境。
高移動性:當(dāng)3G用戶在郊區(qū)室外以120公里每小時的速度移動時,采用144kbps的數(shù)據(jù)傳輸速率。
完全移動性:當(dāng)步行者在郊區(qū)室外以低于120公里每小時的速度移動時,數(shù)據(jù)傳輸速率可以達(dá)到
384kbps。

受限移動性:在低移動性的固定的室內(nèi)及小范圍的室外環(huán)境,數(shù)據(jù)傳輸速率至少能達(dá)到2Mbps。

三、3G具體業(yè)務(wù)

3G的寬頻帶可以提供很多方面的業(yè)務(wù),主要包括：
3.1 音頻

通常,利用各種不同的壓縮算法如微軟或Real網(wǎng)的算法或MPEG-1音頻第三層（MP3）協(xié)議,音頻
或視頻可以通過互聯(lián)網(wǎng)下載（傳輸、存儲或播放）或?qū)崟r播放。有了3G,MP3文件就可以通過一
個專門的服務(wù)器從空中直接下載到你的電話中。

從互聯(lián)網(wǎng)通過固定的長途電話和電纜下載多媒體到PC機(jī)很大程度上依賴于帶寬,因?yàn)閳D像和有
效服務(wù)的質(zhì)量與可用帶寬成反比。目前,由于帶寬的限制,用戶只能通過固定的網(wǎng)絡(luò)先上網(wǎng),將
文件下載到自己的便攜設(shè)備,隨后再觀看和收聽,通過移動通信網(wǎng)還得不到實(shí)時的音頻和視頻。
因?yàn)榧词故呛芏痰穆曇羝瑪喽紩�占用很大的空間。

對于需要高速的移動數(shù)據(jù)的移動音頻業(yè)務(wù),帶寬越寬越好棗這正是3G對于移動多媒體如移動音
頻和視頻的魅力所在。預(yù)計(jì)在未來的四年中將會出現(xiàn)移動電話和日常消費(fèi)品的融合,到那時我
們將能夠通過下一代移動設(shè)備在任意的時間,任意的地點(diǎn)獲得有關(guān)聲音、互聯(lián)網(wǎng)或音樂的數(shù)據(jù)。

3.2 通過互聯(lián)網(wǎng)協(xié)議傳送聲音

3G在音頻方面另一項(xiàng)業(yè)務(wù)就是VoIP（Voice over IP）能夠通過互聯(lián)網(wǎng)向全世界任意地點(diǎn)發(fā)送
呼叫,而價格與本地呼叫相同的一項(xiàng)業(yè)務(wù)。隨著3G及更高速率的2.5G 技術(shù)如EDGE、 VoIP的發(fā)
展,VoIP將第一次應(yīng)用于移動電話。在一次呼叫中,VoIP可以作為一種常規(guī)業(yè)務(wù)。

由于VoIP需要很寬的帶寬,因此為了減小IP干線延遲和掉包的可能性,通常需要非常高的切換
速率。另外,VoIP與標(biāo)準(zhǔn)的語音業(yè)務(wù)可以同時存在。

3.3 靜態(tài)圖像

靜態(tài)圖像如照片、圖畫、信函、明信片、賀卡、演示文稿和靜態(tài)網(wǎng)頁可以象通過固定電話網(wǎng)
傳送一樣通過移動通信網(wǎng)進(jìn)行發(fā)送和接收。

帶寬和時間這兩種影響因素是成反比的。帶寬越寬,傳送圖片所需的時間越短,反之亦然。這
就是為什么直到現(xiàn)在圖像的傳送才成為一種廣泛流行的非語音移動業(yè)務(wù),因?yàn)樵谝�入移動�?shù)據(jù)
包之前,特定的低數(shù)據(jù)傳輸速率需要花費(fèi)太長的時間。

圖片文件的大小取決于圖形的分辨率和壓縮的形式。典型的每幅JPEG格式的圖片大小為50K至
100K,用移動數(shù)據(jù)包可以迅速的傳送,進(jìn)行幾乎實(shí)時的發(fā)布。

3.4 移動圖像

在移動環(huán)境下發(fā)送移動圖像有幾種情況：監(jiān)視停車場或建筑物的入侵者或竊賊,從救護(hù)車向醫(yī)
院傳送病人的圖片及視頻會議等。

移動圖像的傳送是GPRS和3G終端的一項(xiàng)業(yè)務(wù),也許它可以支持更高的數(shù)據(jù)傳輸速率,但通過微
軟的Netmeeting召開一次視頻會議,即使1M字節(jié)的數(shù)據(jù),傳送的視頻圖像都達(dá)不到平滑�；蛟S
改進(jìn)的壓縮技術(shù)可以使得通過64kbps的帶寬傳送的視頻圖像的質(zhì)量還可以讓人接受。
3G的目標(biāo)就是：進(jìn)一步提高帶寬,通過移動通信網(wǎng)進(jìn)行高質(zhì)量圖像的傳送。將所有的移動視頻
和圖像傳送業(yè)務(wù)移植到3G載體中。到那時,所有這些過程都可以從互聯(lián)網(wǎng)站上下載。

3.5 虛擬本地環(huán)境

環(huán)球移動電話業(yè)務(wù)（UMTS）又稱為虛擬本地環(huán)境（VHE）,即實(shí)現(xiàn)用戶的無縫接入,在任何地方
接受不論來自家庭、辦公室或運(yùn)動中的信息感覺都象是在本地。VHE針對的主要是漫游用戶
（全部移動電話用戶的一小部分）。

如果將VHE的全球一致性模塊（UIM）放入任意的終端設(shè)備,VHE還能進(jìn)行其它更有用的業(yè)務(wù)。
而如果智能卡能夠獲得更廣泛的支持,這些終端設(shè)備還可以不是移動設(shè)備。

雖然在切換設(shè)備中（用戶可能擁有多個不同構(gòu)造的3G設(shè)備）和非移動業(yè)務(wù)如身份鑒定和移動
銀行中,智能卡也非常有用,但它們的存儲容量非常有限,隨著電子郵件和其它的業(yè)務(wù)在全球
得到廣泛的應(yīng)用,互聯(lián)網(wǎng)越來越普及,無論有沒有智能卡,通過任意的瀏覽器都可以訪問互聯(lián)
網(wǎng)業(yè)務(wù)。

3.6電子代理

電子代理在未來的移動通信中將發(fā)揮重要的作用,它主要用來進(jìn)行網(wǎng)上搜索并將結(jié)果匯報(bào)給
用戶,這是一種處理移動業(yè)務(wù)的有效方式。

當(dāng)然,3G設(shè)備將比今天的移動電話更多的融入人們的生活。它們可以作為電子助手、電子秘
書、電子顧問和電子管理員�；蛟S,十年內(nèi),我們的移動設(shè)備就可以喊我們起床、幫我們閱讀
電子郵件、預(yù)定食品、告訴我們最好的工作路線、提醒我們開會。這其中的關(guān)鍵問題是這些
過程人為或計(jì)算機(jī)產(chǎn)生并控制的程度及這些設(shè)備能夠“學(xué)習(xí)”我們的個人喜好并做出相應(yīng)的
處理的程度。

3.7 下載軟件

21世紀(jì),軟件將越來越多的從網(wǎng)上下載而不是購買包裝的產(chǎn)品。文件傳輸業(yè)務(wù)也是這樣。例
如,如果你需要WinZip 或 Abode Acrobat用以閱讀文件,你就可以從3G網(wǎng)絡(luò)下載到你的3G終
端設(shè)備。

下載時間取決于你的調(diào)制解調(diào)器的速度和要下載軟件的大小。
各類業(yè)務(wù)的最佳載體
以下列出了各類業(yè)務(wù)的最佳載體：

四、結(jié)論

第三代移動通信必將為移動多媒體帶來高速的數(shù)據(jù)傳輸帶寬、完善的移動終端和各種新的
業(yè)務(wù),為通信注入新的活力。從各方面考慮,第二代移動通信系統(tǒng)將在較長時間內(nèi)與第三代
系統(tǒng)共存。我國擁有世界上最大的移動通信市場,抓住機(jī)遇,發(fā)展我國電信事業(yè),實(shí)現(xiàn)第二
代系統(tǒng)向第三代系統(tǒng)的平穩(wěn)過渡,是現(xiàn)在值得關(guān)注和積極研究的重要問題。

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1. Introduction to 3G

After the development of more than to years, communication system has developed from original private network to current public network covering most districts of the whole world; from original parent zone network construction to current cellular one; and from analog network to digitae public network. After 1G and 2G developments, communication system has entered process of transition from 2G to 3G. With huge progress of communication service and rapid increase of communication quantity, current 2G shows shortage in supporting global roaming, frequency spectrum usage rate and digitae . Though GSM抯 Phrase 2+ supports higher data transmission rate, it is only complementary to 2G and is based on sacrifice of other subscribers?benefit and is not good to system subscribers. 3G comes out in this situation. 3G make communication world towards media integration and fields incorporation and Internet, IP technology and mobile communication will be integrated. The rapid development of 3G mobile Internet will inevitably bring important revolutions in each respect.

◇People will more use eyes more often instead of ears. Eyes will become a main tool to get information and knowledge from 3G.
◇Data service of 3G (non voice) will be totally different from traditional voice service.
◇Mobile communication will be the same as fixed one in capacity and most people will only own one mobile phone.
◇Mobile phone will be an inevitable part of people. It will be the core to lead people抯 life. It can help to realize the dream to communicate with others wherever, whenever and whoever.
◇3G is based on CDMA while 2G on TDMA which is widely used.
◇Mobile communication vendors in America, Japan and Europe have their own technologies but now they have been unified to one standard. So independent wireless development road and leading position of Europe wireless are in challenge.

2. 3G standard

2.1 3G standardization process

Early in 1985, ITU has brought the concept of 3G mobile communications which is called Future Public Land Mobile Telecom System (FPLMTS), and it is changed as IMT-2000 in 1996. Because of the important function of mobile communication in future information industry, government, telecom operators as well as manufacturers in each country are all active to participate the making of 3G standard. Till September 1998, 16 RTTs proposals are presented: Except from 6 satellite interface solutions, there are 10 ground wireless interface solutions and are mainly divided into two types: CDMA and TDMA. Among them, CDMA is in a leading place. These technologies cover W-CDMA in Europe, cdma2000 in America and TD-SCDMA in our country but the focus is W-CDMA and cdma2000.
2.2 3GPP

In October 1998, 3G partnership plan (3GPP) is released. This standard organization is comprised of ETSI in Europe, CWTI in China, ARIB in Japan, TTA in Korea and TI in America. Its aim is to maked out standard with GSM as core network and UTRA as wireless interface. In January 1999, 3GPP2 is officially set up and this organization includes TIA in America, CWTS in China, ARIB in Japan and TTA in Korea etc. Its aim is set set up standard with ANSI/IS-41 as core network, cdma2000, WUCI36 as wireless interface. The cooperation spirit ameng standard organizations in the world greatly accelerates standardization process of 3G. In the first half of year 1999, global IMT-2000 standard gets great progress and this standard can satisfy demands of different technical entities---GSM, CDMA and TDMA in politics and commerce.

2.3 Air interface mode

IMT-2000 in 3G is a standard based on CDMA. This standard includes three free operation modes and each mode can operate through GSM-MPA and IS-41 network construction. The three modes are:
In three operation modes, one is for Europe and Asia, one for Japan and the third for America. A little similar to original 2G mode, a major change is that Japan has entered GSM union of Europe and adopted WCDMA.
Strictly speaking, if including DECT (IMT FT) and EDGE (IMT SC or IWC 136), final IMT-2000抯 ITU proposal includes five ground wireless access standards.
There are two (current) main core network standards in three wireless access modes: GSM MAP and TIA IS-41 (communication United, standard organization in Britain). In mobile communication network, core network is service that wireless access network need to connect. Wireless access network is part of mobile communication network and is used to handle subscribers access problems concerning wireless base stations and other nodes.

2.4 3G data transmission rate

ITU has brought out the lowest data transmission rate that IMT-2000 standard must support. This should define according to the mobility of ongoing calling. That is, the data transmission rate that 3G could support depends on the environment which call happens.
High mobility: When 3G subscribers moves with 120km/h outdoors, 144kbps rate transmission rate is adopted.
Complete mobility: When walkers move outdoors at a speed lower than 120km/h, data transmission rate could reach 384kbps.
Limited mobility: In the environment of fixed indoors place and small zone outdoors with low mobility, data transmission rate can reach at least 2Mbps.

3 .3G services

3G broad frequency band may provide services in many respects which include:
3.1 Voice frequency

Usually, with all kinds of compression algorithms like Microsoft or algorithm of Real network or MP3 protocol of MPEG-1, audio or video can download through Internet (transmission, restore or broadcasting) or real time broadcast. With 3G, MP3 documents may directly download through a dedicated server from air to your phone.
It greatly depends on bandwidth to download multimedia from Internet through fixed long distance phone and cable to PC, because image and quality of effective service are in converse ratio with available bandwidth. At present, because of limit of bandwidth, users can only be online through fixed network and download documents to their own portable devices, then watch and listen. Users cannot get real time audio and video through mobile communication network since very short voice segment will take a lot of space.
To mobile audio service which needs high-speed mobile data, the broader of the bandwidth, the better桾his is just the charming point of 3G to mobile media like mobile audio and video. It is estimated that in the coming four years, mobile phone will emerge with daily consumption. At that time, we will be able to obtain data about voice, Internet and music through next generation mobile device at any time and any place.

3.2 Transmitting voice through Internet protocol

Another service of 3G in audio is VoIP (Voice over IP)---can send calls through Internet to anywhere in the world while the price is the same as local ones. With the development of 3G and higher rate 2.5G technology like EDGE, VoIP, VoIP will be used in mobile phone at first time. In a call, VoIP can be used as a regular service.

3.3 Static images

Static images like pictures, drawings, letters, postcards, greeting cards, demonstration files and static websites can be sent and received through mobile communication network as through fixed phone network.
Bandwidth is in converse ratio with time. Broader bandwidth needs shorter time to transport picture and it is the same with contrary condition. This is the reason why picture transmission becomes a popular non-voice mobile service until now. Before import of mobile packet, data transmission of specific low rate needs a lot of time.
The size of picture documents depends on resolution of picture and format of compression. The size of typical JPEG format is 50K to 100K. It can make fast transpontation with mobile packet, almost real time release.

3.4 Mobile images

There are several conditions to send mobile images in mobile condition: Monitoring invader or burglar in parking lot or building, transmitting picture of patient and video from ambulance to hospital.
The transmission of mobile image is a service of GPRS and 3G terminals but it may support higher data transmission rate. But through Microsoft抯 Netmeeting to hold a video conference, even using 1M byte data, the transported video image can not reach smoothly. Maybe enhanced compression technology will make quality of video image transported through 64kbps bandwidth acceptable.
The aim of 3G is: further increasing bandwidth and transmitting high quality image through mobile communication network. Transplanting all mobile video and image to 3G carriers. At that time, all these process will be downloaded from Internet.

3.5 Virtual home environment

Universal mobile telephone service (UMTS) is also called virtual home environment (VHE). That means seamless access of users and users will feel just like home when they receive information at anywhere from home, office or in moving state. VHE is mainly facing roaming users (a small part of whole mobile users).
If the UIM of VHE is put in any terminal device, VHE can also perform other useful services. If intelligent card could obtain wider support, these terminal devices can even be non-mobile devices.
Though in switch devices (users could own many 3G devices with different constructions) and non-mobile service like identity certification and mobile bank, intelligent card is also very useful, but their storage capacity is very limited. With wider application of e-mail and other services, Internet is getting more and more popular. With or without intelligent card, users can visit Internet service through any browsers.

3.6 Electronic agency

Electronic agency will play an import role in future mobile communication. It is mainly used to make network search and report result to users. This is an effective way to handle mobile service.
Certainly, 3G devices will emerge into people抯 life deeper than current mobile phone. It can act as electronic assistant, electronic secretary, electronic consultant and electronic manager. Maybe in ten years, our mobile device will wake us up, help to read e-mail, reserving food, telling us best working path and alarming us for conference. The key problem is that these devices can 搇earn?our personal interest thus make out proposal accordingly.

3.7 Downloading software

In 21st century, software will download from network instead of purchasing packed products.
Documents transmission service is the same. For example, If you need WinZip or Abode Acrobat to read file, you can download from 3G network to your 3G terminal device.
Download time depends on rate of your modem and size of the so ftware to be downloaded .
Best carriers of all kinds of services
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The following gives best carrier of all kinds of services:
4.Conclusions

3G will inevitably bring mobile multimedia with high-speed data transmission bandwidth, complete mobile terminal and all kinds of new service and put new energy in communication. Considering from all respects, 2G will coexist with 3G for a long time. We owns biggest mobile communication market in the world. It is very important to catch opportunities and develop our communication to realize smooth transition from 2G to 3G.