基于MATLAB的OFDM接收系统设计与仿真 毕业论文.doc

基于MATLAB的OFDM接收系统设计与仿真 摘　　要 OFDM即正交频分复用技术，实际上多载波调制的一种。其主要思想是：将信道分成若干正交子信道，将高速数据转换成并行的低速子数据流，调制到子上传输。OFDM Receiver Design and Simulation Based on MATLAB ABSTRACT OFDM, which is short for Orthogonal Frequency Division Multiplexing, is actually one of the multi-carrier modulations. The main idea of OFDM is to split the channel into a number of orthogonal subchannels and the high-speed data signals into a number of parallel low-speed data signals that are transmitted simultaneously over numbers of subcarriers. This technology greatly improves the channel capacity and transmission rate of the wireless communication system and effectively resists to multipath fading interference and inhibits narrowband noise. Such a good performance has brought widespread concern in the communication area. In this thesis, based on the FFT algorithm, an OFDM receiver system is designed and simulated on a computer. This article focuses on the OFDM receiver design and simulation and details the components and design of each module of the system, and then the demodulation of the OFDM signals transmitted through AWGN channel. The entire process is realized under the MATLAB simulation environment. And then it analyzes the receiver system simulation results and performance, through which we get the relation between SNR (signal to noise) and BER (bit error rate), providing a great numbers of useful datas for the concrete realization of the system, and laying a solid foundation for further improvement of OFDM communication system. Key words：ultiplexing)；MATLAB；Receiver System；Design and Simulation 目　　录 1　引言 1 1.1　课题研究背景及意义 1 1.2　课题发展历程现状及前景 2 1.3　可行性分析 2 1.4　本文主要研究工作和内容安排 2 2　OFDM基带系统的原理 4 2.1　单载波与多载波通信系统 4 2.1.1　单载波通信系统 4 2.1.2　多载波通信系统 4 2.2　频分复用与正交频分复用 5 2.2.1　频分复用(FDM) 5 2.2.2　正交频分复用(OFDM) 6 2.3　OFDM技术的优缺点分析 7 2.4　OFDM技术的基本理论及算法 8 2.4.1　OFDM基本原理 8 2.4.2　OFDM基础理论 8 2.4.3　OFDM核心算法 10 3　OFDM接收系统设计 11 3.1　OFDM整体基带系统框图 11 3.2　OFDM接收系统设计 12 3.2.1　串并变换 12 3.2.2　去循环前缀CP 12 3.2.3　FFT 1