Design Of The Demodulation And Modulation Quality Test System For DVB-T

In recent years,the digital TV industry has made great progress,and the high quality digital TV transmission standard is one of the important research contents.As the European research and development of terrestrial digital video transmission standards,DVB-T(Digital Video Broadcasting Terrestrial)is currently one of the most flexible and widely used standards.However,the terrestrial transmission environment has a great impact on the RF signal transmission,and most of the current equipment for the analysis and measurement of the vector signal is imported,and the corresponding test software is expensive and difficult to expand.Therefore,it is of great significance to design a DVB-T demodulation and modulation quality test system for scientific evaluate the DVB-T signal transmission environment and the modulation quality indicators.The main contents of this paper are as follows:(1)Explain the basic theory of OFDM,interpret the DVB-T standard,the DVB-T transmitter system is introduced,and the design scheme of DVB-T receiver is presented.(2)Research the main algorithm in DVB-T demodulation: bandwidth estimation algorithm of mode decision algorithm,pattern recognition and synchronization and channel,and proposes an improved DVB-T channel estimation algorithm,can improve the algorithm accuracy and reduce the complexity of the algorithm.(3)Design the DVB-T demodulation and modulation quality testing system,the requirement analysis,the overall frame design of the test system,and the implementation methods of each module are introduced.(4)Test and analysis of the DVB-T signal demodulation and modulation quality testing system are carried out by selecting the test cases,which verifies the validity of the algorithm and the correctness of the test system.