Baseband Design Of Digital Mobile Radio Protocol Based On OMAP-L138 Platform

DMR communication protocol published by European telecommunications standards institute in 2006, aims to private network of mobile communication users with low-cost narrow-band digital clustering system, with the advantage of open protocol standard, clear and concise technical agreement, efficient spectrum utilization, strong confidentiality. At the same time support the transition of analog signals to digital signals, at present has been widely applied in Europe, in China also gradually become one of the mainstream digital trunking communication protocol.The main work of this thesis is to design a network simulation platform of DMR protocol, and analyze the performance of DMR protocol under different network scenarios. Then complete the small and low-power design of baseband module of the DMR protocol, with the dual core and low-power OMAP-L138 chip, to achieve the baseband module hardware design.Firstly, finish the study of DMR baseband protocol, mainly about the basic framework and the key technology of the DMR protocol, included the basic burst structure, structure of main control signaling, the channel access process of mobile terminal, high-level protocol state transition. Then expound the main coding and decoding principle used by DMR protocol, and then accomplish the simulation analysis of the bit error rate of BPTC code. All the work above provides a theoretical support for further research.And then with the help of OPNET software design a model of DMR protocol of mobile terminal and relay station, to build the network simulation platform, included different network scenarios made up of direct mode and the relay mode, simulate and analyze the relation between DMR communication system channel capacity, channel access delay, channel collision probability and the load of each node of various networking scenarios, to assess the DMR communication network performance for practical use.Finally based on OMAP-L138 chip, achieve the design of small size and low power consumption of DMR protocol baseband module, including hardware PCB design and debug, use dsplink development tools to design data communication of thethree layer architecture of DMR protocol, modulation and demodulation, channel coding on physical layer, the construction of burst and signaling and analysis of control on data link layer, the high state conversion functions on call control layer. With all these work, accomplish the design requirements of baseband module.