OFDM System Design And Simulation

The basic principle of OFDM is to split a high-rate data stream into a number of lower-rate streams that are transmitted simultaneously over a number of subcarriers. The benefits of OFDM are lower multi-path distortion, resiliency to inter-symbol interference and high spectral efficiency.In this thesis, basing on the FFT algorithm, a based-band OFDM system is analyzed, designed and simulated on a computer. The thesis mainly consists of four parts.In the first part, the theory of OFDM, the traditional continuous-time model and discrete-time model are introduced. Then some improvement is made, at the same time a new one is built for the simulation. In the second part, after the channel coding system is designed, an integrated base-band OFDM system is constructed. Channel coding uses the classic outer, inner coding structure and QAM. Outer coding consists of RS coding and convolution interleaving. Inner coding consists of punctured-convolution coding, bit interleaving and symbol interleaving. In this part the synchronization tech is also studied. The third part is about the simulation and the results' analyses. Finally, Problems about the system realization using DSP or FPGA are discussed and three schemes are presented for different conditions in the last part.In conclusion, an integrated base-band OFDM system is designed and simulated, which provides lots of useful data for realizing the system and for advanced research.