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回顾现代无线接入技术的发展历史,从60年代起就出现了最早的无线接入技术,它以频分复用、模拟调制、模拟信令为代表,产品为大区制移动通信和无线用户环路设备。直到70年代末,Bell实验室提出了蜂窝小区、频率复用的概念,无线通信技术才进入今天的发展轨道。 作为现代无线通信技术的起点,即第一代峰窝移动通信技术,其特征是在网络上使用了峰篇小区的概念,多址方式为频分多址(FDMA),双工方式为频分双工(FDD),直接使用模拟信号进行模拟调制等等。第一代
Recalling the history of the development of modern wireless access technology, the earliest wireless access technologies have emerged since the 1960s. They are represented by frequency division multiplexing, analog modulation and analog signaling. Products are large-area mobile communications and wireless users Loop equipment. Until the late 1970s, Bell Labs put forward the concept of cell and frequency reuse, and wireless communication technology entered the development track of today. As the starting point of modern wireless communication technology, that is, the first generation of cellular mobile communication technology, which is characterized by the use of peak cells on the network concept of multiple access for the frequency division multiple access (FDMA), duplexing frequency Duplex (FDD), direct analog signal modulation and so on. First generation