其他摘要：With the purpose of revealing the differences between public communication system and digital trunking system, a detailed introduction of the characteristics, network structure and key services provided of the latter was made. For the further study of digital trunking system, we then carried out a thorough research on the four digital trunking protocols—TETRA, iDEN, GoTa and GT800—that are most widely used in China. It not only analyzed the technological characteristics of these protocols, but also introduced their latest versions, technical developments and directions of further evolution respectively, which made the present de-velopment situation of digital trunking system clear at a glance.
