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数字通信以其优异的传输特性和容易对各种信息源匹配等特点,日益受到重视。因此,我国也在积极发展数字通信系统。由于我国数字通信方面的基础还比较薄弱,尚不能很快地满足当前的急需,因此,在短期内将是尽快地发展模拟通信手段。这样,在我国通信网的结构上,也必然会出现模拟网和数字网的并存问题。因此,在研制数字通信设备的同时,还必须研究模拟通信系统与数字通信系统的相互转接的问题。模拟系统与数字系统相互转接的方法可如图1所示。由图看出,转接方法可分为两大
Due to its excellent transmission characteristics and easy matching of various information sources, digital communication is gaining more and more attention. Therefore, our country is also actively developing digital communication system. As the foundation of digital communications in China is still relatively weak, we can not meet the immediate needs urgently. Therefore, in the short term, it will be as fast as possible to develop analog communications. In this way, the structure of China’s communications network, there will inevitably be the coexistence of analog networks and digital networks. Therefore, in the development of digital communications equipment, we must also study the analog communications system and digital communications system, the issue of mutual transfer. Analog and digital systems can be transferred to each other as shown in Figure 1. Seen from the figure, the transfer method can be divided into two major