The Research And Application Based On 350MHz Broadcasting Distribute Control Trunking System

The 350MHz wireless communication system is used in the National Public Security Department wireless communication and dispatch system. It has been playing a crucial role in daily police service, security tasks, all types of emergencies and security in major economic and sport activities.But in recent years, with the rapid development of the urban construction and the changes of police affairs, the existing system shows its disadvantage on the number of mobile terminal and coverage area. The current system also has problem of being unstable, poor communication during cross-regional dispatching, low frequency utilization, etc.To meet current and future requirements of police work for wireless communication system, the current system is going to be modified according to the Ministry of Public Security's requirements with unified functions including leadership, planning, networking and management. So, Dongli 350MHz wireless communication system is going to be modified into a new one which has advantage on coordinated operations, the multi-police force joint response capacity, maintenance and efficiency. The new one provides solutions to most problems in the field operations and make it better for public security dispatching services.The upgrade project is a combination of MPT-1327 with the common frequency broadcast technology。The system is an ordinary cluster communication system upgrade and has prepared for future digital mobile communications systems. It is an integration of frequency allocation, voice election, GPS global positioning technology, channel allocation, packet switching and other advanced technologies, which solves the problems like high frequency utilization of large amount of users under the coverage of a wide range and other issues. It has well served the police dispatching service.This paper introduces the basic network and main applications of distributed trunking communication system structure,explaines the Dongli Distribute Control Trunking System with the broadcast system design and application methods, through the comparison test of construction with terminal's signal strength, voice quality and termination rates. Finally,with the prospect of police wireless communication system, this paper analyzes the advantages and disadvantages of digital mobile communication system, and points out the problems of upgrade from analog to digital system。...