大麦盒子多少钱一个:What's 3G technolige? please answer it in English.

3G wireless networks are capable of transferring data at speeds of up to 384Kbps. Average speeds for 3G networks will range between 64Kbps and 384Kbps, quite a jump when compared to common wireless data speeds in the U.S. that are often slower than a 14.4Kb modem. 3G is considered high-speed or broadband mobile Internet access, and in the future 3G networks are expected to reach speeds of more than 2Mbps.

3G technologies are turning phones and other devices into multmedia players, making it possible to download music and video clips. The new service is called the freedom of mobile multimedia access (FOMA), and it uses wideband code division multiple access (W-CDMA) technology to transfer data over its networks. W-CDMA sends data in a digital format over a range of frequencies, which makes the data move faster, but also uses more bandwidth than digital voice services. W-CDMA is not the only 3G technology; competing technologies include CDMAOne, which differs technically, but should provide similar services.

FOMA services are available in a 20-mile radius around the center of Tokyo, the company plans to introduce it to other Japanese cities by the end of the year. But services and phones are expensive and uptake of this market is expected to be slow.

所谓3G，其实它的全称为3rd Generation，中文含义就是指第三代数字通信。1995年问世的第一代数字手机只能进行语音通话；1996到1997年出现的第二代数字手机便增加了接收数据的功能，如接受电子邮件或网页；第三代与前两代的主要区别是在传输声音和数据的速度上的提升，它能够处理图像、音乐、视频流等多种媒体形式，提供包括网页浏览、电话会议、电子商务等多种信息服务。
相对第一代模拟制式手机(1G)和第二代GSM、TDMA等数字手机(2G)，3G通信的名称繁多，国际电联规定为“IMT-2000”（国际移动电话2000）标准，欧洲的电信业巨头们则称其为“UMTS”通用移动通信系统。

该标准规定，移动终端以车速移动时，其传转数据速率为144kbps，室外静止或步行时速率为384kbps，而室内为2Mbps。但这些要求并不意味着用户可用速率就可以达到2Mbps，因为室内速率还将依赖于建筑物内详细的频率规划以及组织与运营商协作的紧密程度。

目前已经进行商业应用的2.5G移动通信技术是从2G迈向3G的衔接性技术，由于3G是个相当法浩大的工程，所牵扯的层面多且复杂，要从目前的2G迈向3G不可能一下就衔接得上，因此出现了个介于2G和3G之间的2.5G。HSCSD、GPRS、WAP、EDGE、蓝牙(Bluetoot)、EPOC等技术都是2.5G技术。
HSCSD这是GSM网络的升级版本，能够将传输速度大幅提升到平常的二至三倍。目前新加坡M1与新加坡电讯的移动电话都采用HSCSD系统，其传输速度能够达到57.6kbps。

GPRS由于具备立即联机的特性，对于使用者而言，可说是随时都在上线的状态。GPRS技术也让服务业者能够依据数据传输量来收费，而不是单纯的以联机时间计费。这项技术与GSM网络配合，传输速度可以达到115kbps。

EDGE完全以目前的GSM标准为架构，不但能够将GPRS的功能发挥到极限，还可以透过目前的无线网络提供宽频多媒体的服务。EDGE的传输速度可以达到384kbps，可以应用在诸如无线多媒体、电子邮件、网络信息娱乐以及电视会议上。

WAP是移动通信与互联网结合的第一阶段性产物，也是大家听说最多的。这项技术让使用者可以用手机之类的无线装置上网，透过小型屏幕遍游在各个同站之间。而这些同站也必须以WMl(无线标记语言)编写，相当于国际互联网上的HTML(超文件标记语言)。

3G时代展望

日本移动通讯巨人NTF DoCoMo已于10月1日开通全球第一个3G服务，该服务基于WCDMA标准。目前，亚洲成为3G发展最快的地区，欧洲紧随其次，美国由于不太热心而在技术准备上远远落后。除了动作最快的日本和韩国，泰国、香港也已经发出3G牌照。台湾即将发放工3G牌照。预计内地在年底前表出3G牌照，市场预期将发行两到三个拍照三个牌照。

3G (wCDMA, CDMA-2000, UMTS, FOMA) in Japan FAQ
1. What are third generation (3G) wireless communications? Second generation (2G) cellular data networks in Japan deliver data rates up to 9.6 kbps for upload and up to 29.8 kbps for download.
PHS networks in Japan deliver data rates up to 128 kbps for terminals which are not moving at high speeds (e.g. PHS does not connect well in high-speed trains).
Third generation (3G) wireless networks in Japan deliver datarates from 64 kbps for upload and on the order of 200 kbos for downlad. Increasingly 3G networks in Japan are upgraded to deliver data connection rates on the order of 2 to 10 Mbps. These higher speeds allow the transmission of video and two-way video telephony, rapid download of movie sketches, music and JAVA applications. Other data connections, e.g. download of information or JAVA applets, are also several times faster on 3G networks then on older 2G networks.
In Japan there are three parallel, independent and competing 3G networks. Costs to the carrier are lower, so that competition drives prices down. 2. Which networks are there in Japan and how many 3G users are there? KDDI/AU, NTT-DoCoMo and Vodafone operate 3G mobile networks in Japan. The following figure shows the user numbers as of January 2005:

2. What is the "killer application" for 3G? Is there one at all? If there is a "killer application" for 3G, its mobile music! Chaku-Uta downloads on KDDI-AU mobile phones have similar download numbers as iTunes in the US with a very much smaller potential user pool. One can therefore safely say, that mobile music downloads seem to be substantially more attractive for paying users than conventional fixed line internet music downloads.