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由日本 NTT 提出的“个人通信”,从根本上改变了现有通信的形象,被认为继 PSTN和 ISDN 之后的第三代通信系统。NTT 计划从1992年开始在大城市首先投入使用。迄今为止,为实现任何时间、任何地点与任何人实现自由通信的理想,主要侧重于发展无线移动通信,但仅靠无线移动通信实际上存在许多难以在短期内解决的问题,诸如扩大业务范围所费资金庞大、所需时间漫长、通信费用昂贵等等。NTT 的“个人通信”
The “personal communication” proposed by Japan’s NTT fundamentally changed the image of the existing communication and was considered as the third generation communication system following the PSTN and ISDN. The NTT project was first put into operation in the big cities since 1992. So far, in order to realize the ideal of free communication with anyone anytime, anywhere, the main focus is on the development of wireless mobile communication. However, there are actually many problems that are difficult to be solved in the short term by wireless mobile communication only, such as expanding the scope of business Fees and funds are huge, the time required for a long, expensive communications and so on. NTT’s “personal communications”