Design Of Var Multi-services Optical Transmission And Switching Integrated System

VAR multi-services optical transmission and switching integrated system can satisfy the requirement of future monitoring system. It can replace many equipments in traditional monitoring system, and it is very simple and useful.The backgrounds, principle and some important technologies are described in the thesis. The clock synchronization of VAR is studied as emphases, and it is divided into two parts for designing. SDH technologies are used in VAR transmission and switching integrated network, and adaptive synchronous algorithm is used between VAR center and terminal.During the study of synchronization between VAR center and terminal, delay variety of packets network which between VAR center and terminal is measured, and the result shows that the delay variety of packets network is very small. So the adaptive synchronous algorithm for clock recovery can be used at terminal. Then the thesis analyzes the adaptive synchronous algorithm[18] in detail. And introduces Least Square Linear Regression based clock recovery algorithm at terminal. The algorithm has the ability to filter out buffer level flucation efficiently and remove the negative contribution of delay jitter in clock recovery. The new algorithm enables the terminal clock to be synchronized with the VAR center more accuracy. The thesis also try to adopt weighted average algorithm to smooth the packet jitter, and analyses performance of the algorithm. The algorithm is implemented on FPGA circuit board. At last, a new scheme about detection and processing of packet lost is gived in thesis.