Research And Implementation Of The Bridge Between Public Network-based Trunking System And PDT System

Trunking communication system has been widely used in the railway and airport communication,and the trunking system based on the Internet now also plays an important role in military,transport and public security communication.Public Network-based Trunking System(PNTS)is developed from TETRA and DMR systems.PDT(Police Digital Trunking)communication system standard is an independent innovative digital trunking standard,which is suitable for China.And it is a completely independent intellectual property rights.PDT System is a dedicated network trunking system using this standard.To realize the connection of two systems,we use the Bridge.The bridge is able to manage the data flow and voice flow between two sysytems.The Bridge not only can expend the range of communication network,but also improve the effectiveness,reliability and practicality of the network.Based on the domestic and international development of the Bridge,this paper does the research as following.Firstly,the structure of PNTS,PDT system and the Bridge is analyzed,and the mode of PDT System and functions of Bridge is described specifically in this paper.Secondly,the structure of the Bridge in different modes is designed,the process such as single call,group call and SMS forwarding is described,and the API between Bridge and PNTS,the API between Bridge and PDT System are indicated in this paper.Thirdly,with the Windows operating system,using VC ++programming language based on MFC,the assembly and functions,the Bridge program is designed in in this paper.Finally,utilizing Wireshark and serial debugging tools etc,the Bridge program is debuged and test in this paper.The test results shows that the Bridge can achieve the function of single call,group call and SMS forwarding,and meet the requirements of signaling and voice intercommunication of two sysytems.