| The dissertation is written according to the merged scheme raised by union technique work group of national terrestrial digital television broadcasting. Aimed at the problem that good receive and BER performance in a multi-carrier transmission system needs precise channel estimation and equalization, some important existing standards and OFDM technology are firstly introduced. Then estimation method of circular correlation in time domain based on PN sequence with its analysis is described in details. Later is the specific application of this method, fully analyzed and discussed in three kinds of multi-channel of different length and also two equalization methods in two typical channel models: Ricean and Rayleigh channel model. Compared with DVB-T standard, this mothod is better in estimation accuracy test. At last, some improvement and logic designs are completed in this project, FPGA virification in this estimation and equalization system is tested by series of simulations and time-sequential vilifications in hardware system.The work finished is as following:Programme Viterbi hard decoding method and Viterbi soft decoding method using channel information and mapping in Matlab.Write codes of channel estimation and equalization in OFDM system for performance test and BER analysis, included three different estimation methods on condition of three typical channel length, and two equalization methods with/without channel information, then obtain exactly the same results comparing with DVB-T standard.Utilize Quartus II and Modelsim simulation tools for FPGA design; obtain the accurate data of function and time-sequential simulation with resource optimized.Complete the document about fixed-points and floating-points system simulation, design methods for more accurate estimation with less resource consumption. |
