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国际电信联盟ITU早在1985年就提出了第三代移动通信系统的概念，最初命名为FPLMTS（未来公共陆地移动通信系统），后在1996年更名为IMT-2000（International Mobile Telecommunications 2000）。第三代移动通信系统的目标是：世界范围内设计上的高度一致性；与固定网络各种业务的相互兼容；高服务质量；全球范围内使用的小终端；具有全球漫游能力；支持多媒体功能及广泛业务的终端。为了实现上述目标，对第三代无线传输技术（RTT）提出了支持高速多媒体业务（高速移动环境：144Kbps，室外步行环境：384Kbps，室内环境：2Mbps）、比现有系统有更高的频谱效率等基本要

With the technology improved, more and more people want to use 3G technologies. Also, many people would like to know the history of mobile telecommunication technology, like 1G and 2G.

1G refers to the first generation of wireless telecommunication technology. Antecedent to 1G technology is the mobile radio telephone, or 0G. Unlike its successor, 2G, which made use of digital signals, 1G wireless networks used analog radio signals. 1G is only modulated to a higher frequency of typically 150MHz and up. This is done using a technique called Frequency-Division Multiple Access (FDMA).
Today, the about 90% of all subscribers are using second generation wireless telecommunication technology. 2G have the advantages of High-quality sound and security. Besides 2G also offered additional services such as SMS and e-mail.2G technologies are categorized by whether they are based on time division multiple access (TDMA) or code division multiple access (CDMA). The main 2G standards are GSM. It is based on TDMA. However, a coin has two sides. If a 2G cellphone make a call far away from a cell tower, the digital signal may not be enough to reach it.
Now 3G is a hot topic in china. The third generation of mobile networking and telecommunications is also known as International Mobile Telecommunications-2000 (IMT-2000). It is purpose of 3G that providing the fastest speed for surfing on internet or data transmission and better voice quality through the phone.