The Research On Cable TV Network Safe Monitoring And Control System

This thesis discusses and analyses the technology problems for the design and development of CATV Network Safe Monitoring and Control System.Author analyses and introduces the constituting of the system and its principle. The design thought is: on the basis of the previous CATV network, to add a main control unit at the mixer part, and embed a node units in each dual-direction amplifier, accordingly, consititue a safe monitoring and control network. In this dissertation, some key chips of control circuits are introduced. It analyses the theory about PLL-FM and FM signal demodulation, and give out realization of corresponding circuit and characteristic analysis. The thesis presents the analysis about the process of the communication between the computer and the single chip microprocessor inside the main control unit, and gives out the related circuit realization.The thesis gives out the theory analysis and realization of error control code during the digital communication in this system. Moreover, the thesis analyses and expatiate EMC design problems of print circuit board and technique about connecting the ground .