Research on synchronization in communication system

Synchronization is the crucial precondition of information transmission which has a decisive effect on communication systems quality.It's pivotal to have a synchronization system working orderly,reliably and exactly,this question must be resolved first in almost all communication systems.In order to understand the overall synchronization technology,this paper expoud the basic principle of the carrier synchronization,bit synchronization,group synchronization and network synchronization.Realizing methods are also compared and analyzed.Finally performance indices and impact on the communication systems are provided.