Studies Of Experimental System For Communication Theory Based On FPGA

Communications and information technology industry developed rapidly, it had become one of China's pillar industries. With the rapid development of this industry, the demanding of person with professional and practical skills in this field is increasing. Communication experimental teaching reform in University is imperative. Initially each experiment had independent hardware in communication theory experimental equipments. With the development of EDA technology, some manufacturers add CPLD/FPGA to communication experimental equipments independently. FPGA has advantages of high integrated, high-speed and field programmable, it's suitable for high integrated and high-speed sequential computing. This paper summarized the advantages and disadvantages of experimental equipments in existence. It schemes out experimental system for communication theory by using FPGA.This system is provided with comprehensive and systematic, students can achieve validatory and designable experiments on it.This system supplies an opening platform of hardware and software, brings up students practical ability. It can implement all experiments in this paper on unified hardware. It can complete not only solidified experiments, but also developments and validation of electronic. It's benefit for training students practical ability.This paper use the basic model of the digital communication system, divided experimental system for communication theory on FPGA into Signal source module, Sending module,Communication channel simulation module,Receiver module, and Synchronization module. Thereinto, analog singal source adopts DDS technology, which can generate very high frequency accuracy. It can be used as random waveform generator. Sending module and receiver module combined to make Multi-Modem, formed multi-band, multi-wave software radio system. Carrier synchronization adopts All-Digital COSTAS Loop, has good characteristics of the carrier tracking. Bit synchronization adopts Gardner arithmetic, because it is not sensitive to carrier phase.First, this paper introduces the research status and purport of experimental device for communication theory. Second, extracts the contents of the experimental module from each chapter bases on communication system model. And then lists the digital model of each experiment. Third, selects the appropriate FPGA chip type by consulting resource requirements of the various modules, and then gives the hardware design of system. Finally, gives the FPGA implementation, test results and analysis of every module. Through test and actual operation, both of the functions and technical specifications meet the design requirements.