Analysis And Simulation Of OFDM System And Research Based On Cyclic Prefix

With the rapid growth of Very Large Scale Integration (VLSI) technology and Digital Signal Processing (DSP) technology, Orthogonal Frequency Division Multiplexing (OFDM) is becoming more and more widely used in communication areas. OFDM have high spectrum efficiency and can strongly combat multi-path and dispersive channel interface. This paper introduces the principle , the merit and shortcoming of OFDM and analyzes some key technologies in OFDM system. Then analyzes the performance of overcoming inter symbol interference (ISI) and inter channel interference (ICI) of the guard interval (GI) and the cyclic prefix (CP). At the same time emphasizes on cyclic prefix and presents a new algorithm based upon the maximum likelihood estimation algorithm using the relativity of CP, which can resolves synchronization of symbol frame and carrier offset in OFDM system. The improved algorithm can meet the demands of the system easier and its validity is showed by the simulation results. The simulation of the OFDM base-band system using Systemview and Matlab is also put forward in this paper and the results are analyzed. To improve the performance of the OFDM system, channel encoding and interleaving are discussed. The system performance under channel encoding and interleaving is analysed and results of simulation are given. A universal, expandable platform for further research in the performance of the OFDM system is provided.