line telephone

The monitoring system of heat-supply network is composed of control unit of substation,wire telephone network data communication system and computer data center in central control room.

热网监控系统由热力站控制单元、有线电话网数据通信系统和中控室计算机数据中心组成。

With the development of cable and wireless communications and through the comparison of the two transmission technology, this paper focuses on their relationship in the evolution of technology, and then through the graphical chart, illus trates the replacement of fixed-line voice services by mobile voice services, including their fierce competitions.

文中通过有线通信和无线通信的发展历程,对比两种传输技术的特点,着重体现两者在各自技术演进中的相互关系。