卷积码在OFDM系统中的性能分析及仿真  

Analysis and Simulation of Convolutional Code Performance over OFDM System

作　　者：郑翊[1] 

机构地区：[1]中国电子科学研究院,北京100041

出　　处：《无线电通信技术》2013年第6期44-47,共4页Radio Communications Technology

摘　　要：正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)技术作为802.11物理层标准,已经广泛应用于无线通信系统中。通过Matlab编程实现了OFDM系统的仿真,采用高斯白噪声信道,并使用卷积码作为系统的差错编码,对不同编码速率和不同约束长度下的卷积码对OFDM系统带来的误码率影响进行了仿真。结果表明在中低码率情况下使用卷积码作为信道编码可使OFDM系统的抗干扰能力有明显的提升,并且系统的传输时延较小,采用低速率编码结构或增加约束长度都会增强卷积码的纠错能力。Abstract：OFDM is a popular communication scheme in the field of wireless communications. It is regarded as a strong candidate for the 802.11 standard. This test develops an OFDM system which is transmitted under AWGN channel. Matlab simulation programs are created to demonstrate the operation of this system. Convolutional codes are used to improve the performance of OFDM system in this test,different code rates and different constraint lengths of convolutional codes are compared. The simulation results show that using convolutional codes as channel coding could improve the anti-interference capability of OFDM system and decrease the transmission delay,and the correction capability of convolutional codes can be improved by using low-rate coding structure or increasing the constraint length..

关 键 词：OFDM系统 卷积码 编码速率 约束长度 纠错性能 

分 类 号：TN941.4[电子电信—信号与信息处理]