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60年代,以频分复用、模拟调制、模拟信令等为代表的无线接入技术已被采用。70年代,进入了当代无线通信技术的发展轨道。其技术的典型代表是蜂窝移动通信系统,以及用此技术的各种集群电话、无绳电话等设备。80年代,整个通信网的数字化进程加快了,而程控交换、数字传输等技术的成熟,又大大推动了移动通信数字化进程。90年代,人们把目光瞄准了第三代蜂窝移动通信技术,并把重点放在提高频谱利用率、话音质量、降低设备成本等方面。
In the 60s, wireless access technologies represented by frequency division multiplexing, analog modulation, analog signaling, and the like have been adopted. In the 70s, it entered the development track of contemporary wireless communication technology. The typical representatives of its technology are cellular mobile communication systems, as well as various trunked telephones, cordless telephones and other devices using this technology. In the 1980s, the digitization process of the entire communications network was accelerated, and the maturity of program-controlled switching and digital transmission technologies drastically promoted the digitalization of mobile communications. In the 1990s, people focused their attention on third-generation cellular mobile communication technologies and focused on improving spectrum efficiency, voice quality, and reducing equipment costs.