到本世纪末,由于全部通话的50%将涉及移动终端,所以把固定与移动通信网络成功地综合起来就成为关键性的问题.这就要求B-ISDN支持向用户提供移动业务所必要的某些功能.移动通信的应用在过去十年中增长迅猛,预计90年代的发展与之相似.这种增长是从1980年开始的,当时第一代模拟蜂窝移动电话刚进入商用,最近,第二代数字系统(例如:GSM,DECT,数字AMPS,TELE- POINT)已投入使用.尽管这些第二代系统的主要目标是商业用户,但估计它们会在本世纪末形成巨大的市场,而到下个世纪初,其容量将达到极限,将不能满足用户需求的增长.因此,欧洲26个研究机构开始了 By the end of this century, the successful integration of fixed and mobile communications networks has become a critical issue as 50% of all calls will involve mobile terminals, requiring B-ISDN to support some of the necessary Function.Mobile communications applications have grown rapidly in the past decade and are expected to grow similarly in the 1990s.The growth began in 1980 when the first generation of analog cellular mobile phones were first introduced to commerce and most recently the second generation Digital systems such as GSM, DECT, digital AMPS, TELE-POINT have been put in place.Although these second-generation systems are primarily aimed at business users, it is estimated they will form a huge market by the end of the century and by the next century At the beginning, its capacity will reach the limit, will not be able to meet the growth of user needs. Therefore, 26 European institutions began