基于小波包变换的多载波系统的仿真分析  

Simulation on Wavelet Packet-Based Multi-carrier System

作　　者：王飒爽[1] 戴居丰[1] 侯春萍[1] 

机构地区：[1]天津大学电子信息工程学院

出　　处：《电子测量与仪器学报》2007年第2期58-61,共4页Journal of Electronic Measurement and Instrumentation

基　　金：国家自然科学基金资助项目(编号:60372084)

摘　　要：由于基于傅立叶变换的正交频分复用(OFDM)的多载波系统频谱旁瓣较大,为克服符号间干扰(ISI)需加入循环前缀,从而降低系统的频谱利用率。为了提高频谱利用率,改善系统性能,文中设计了一种基于小波包变换的多载波系统,对该系统在各种无线信道下的传输性能进行了分析,并与基于傅立叶变换的OFDM系统相比较。本文的基于小波包变换的多载波系统的信道调制,采用了各种不同的正交小波和双正交小波,仿真结果表明小波的正交性交将影响系统的性能。Orthogonal frequency division multiplexing （OFDM） system based on Fourier transform has high sidelodes and needs to insert a cyclic prefix （CP） to avoid inter symbol interference （ISI）. However, adding CP will decrease the bandwidth efficiency greatly. To improve power spectrum efficiency, a wavelet packet based multi-carrier system is proposed and analyzed in this paper. Comparisons are made between wavelet packet based multi-carrier system and OFDM system based on Fourier transform in different wireless channels. In this paper, we also use various orthogonal and bi -orthogonal wavelets as sub-channel modulation waveform. Simulation results show that the orthogonality of different wavelets will influence the performance of the system.

关 键 词：小波包变换 多载波系统 正交频分复用 小波包基 

分 类 号：TN913.6[电子电信—通信与信息系统]