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在移动通信领域里,采用数字蜂窝标准的全球移动通信系统(GSM)获得了巨大成功,现在它已在世界上133个国家被应用。至去年底,GSM 网络在欧洲已有约9500万用户,在亚洲和非洲它也领导了移动通信的潮流,目前,它正在向美洲市场进军。根据 GSM 协会的统计,去年全世界有1.4亿人使用 GSM 网,这占了全世界数字无线通信市场的60%以上。国际电信联盟(ITU)估算,1999年底,GSM 网的用户增至4亿。现在的蜂窝技术主要是让移动的人们进行语音通信。但是,数据通信的应用正与日俱增,从家电控制网到点播电视、多媒体新闻、电视购物,都离不开数据通信。有人估计,到2005年,在通信(包括有线和无线)领域中数据通信将占主要地位。为了使 GSM 网络能适应即
In the field of mobile communications, the Global System for Mobile Communications (GSM), which is based on the digital cellular standard, has achieved great success and is now used in 133 countries around the world. By the end of last year, the GSM network had 95 million subscribers in Europe and it also led the mobile communications trend in Asia and Africa. At present, it is marching toward the Americas. According to the GSM Association, 140 million people worldwide used the GSM network last year, accounting for more than 60% of the world’s digital wireless communications market. The International Telecommunication Union (ITU) estimates that by the end of 1999, the number of GSM network subscribers had increased to 400 million. The current cellular technology is mainly for mobile people to carry out voice communications. However, the application of data communication is increasing day by day, from the control network of household appliances to the on-demand television, multimedia news, TV shopping, can not do without data communication. It is estimated that by 2005 data communications will dominate in communications (both wired and wireless). In order to GSM network can adapt to that