|
论文编号ZXX288 论文字数:14511,页数:30
摘 要:正交频分复用(OFDM)技术是一种多载波数字调制技术,是第四代移动通信的核心技术之一。相比于一般的数字通信系统,它具有频带利用率高和抗多径干扰能力强等优点,因而适用于高速率的无线通信系统。
本文介绍了OFDM 的基本原理,研究了卷积码,交织技术以及不同调制方式对OFDM系统性能的影响。在给出OFDM系统模型的基础上,用MATLAB语言实现了整个系统的计算机仿真并给出参考设计程序。最后给出在AWGN的信道条件下,卷积码、交织技术和不同的调制方式对OFDM系统误码率影响的比较曲线,得出了较理想的结论。
关键词:OFDM;卷积码;交织;QPSK;16QAM;AWGN信道
Abstract:Orthogonal Frequency Division Multiplexing (OFDM) is a kind of multiple carrier digital modulation technique as well as one of the core techniques of the fourth generation of mobile communication. Compared with ordinary digital communication systems, it has higher bandwidth usage rate and stronger capacity of resisting multi-path disturbance, etc, thus suitable for high-speed wireless communication system.
The thesis introduces the basic principle of OFDM and studies the effect that convolution codes, interlacing technology and different modulating methods have on the performance of the OFDM system. On the basis of OFDM systematic mode, the simulation work has been done together with the designing procedures for reference through use of MATLAB tools. Finally, the BER curves of convolution codes,interlacing technology and different modulating methods in AWGN channels are given and compared. The conclusion is satisfactory.
Keywords:Orthogonal Frequency Division Multiplexing;convolution encoding,;interlacement; quaternary phase shift keying;16 Quadrature Amplitude Modulation;the channel of AWGN |
|