Hardware Design Of DMR Repeater Station And Realization Of Trunking Technology Based On G45

Digital trunking communication is great different from public wireless communication. With its lower-cost, more open and faster connecting, in many fields, digital trunking communication has become an important supplement of the public wireless communication. In recent years, the digital dedicated communication system has been replacing analog dedicated communication system with its advantages of high call quality, high security, difficult to distortion and anti-interference. Among many digital communication system dedicated protocols, DMR protocol is a new open digital dedicated communication system protocol. In the field of digital dedicated communication system, it not only has an important theoretical significant, but also has practical value.The realization of trunking technology is studied in this paper which is required by the second stage of DMR.Firstly, a detail introduction of the development and the current situation of transmitting technology is given. After that, it discusses the signal workflow of both interphone and repeater station and introduces the throughput rate characteristics of transmitting process. On this basis, a simulation is made to compare interphone traffic and call loss rate on the situation of 2-channel and 4-channel.Secondly, the hardware design scheme of the repeater station is proposed. After comparison of many chips, the author designs the circuit of the baseboard and introduces the principle of the design in detail. Then the author introduce the draw process and the principle of PCB.Finally, the author record the result after debugging the successfully made repeater station on every interface and module. After that, the author test the repeater program and debug it,build the baseband of repeater station for trunking experiment, introduce the test of duplex program and gain the voice transmitting experiment result, last analysis the experiment result with theory.Hardware platforms and high-level software development is versatile, the project developed hardware platform and high-level software to verify the feasibility of voice communication under the forwarding mode. Lay the foundation of future development of repeating mode.