改善频谱效率的多维度索引OFDM系统  

Multi-dimensional indexing OFDM system for improving spectral efficiency

作　　者：禹永植[1] 李葛 刘宇 唐佳乐 YU Yongzhi;LI Ge;LIU Yu;TANG Jiale(College of Information and Communication Engineering,Harbin Engineering University,Harbin 150001,China)

机构地区：[1]哈尔滨工程大学信息与通信工程学院,黑龙江哈尔滨150001

出　　处：《应用科技》2024年第5期211-218,共8页Applied Science and Technology

摘　　要：双模离散傅里叶变换–扩展正交频分复用(discrete fourier transform–spreading-orthogonal frequency division multiplexing-discrete multi,DFT-S-OFDM-DM)系统虽然拥有优秀的峰均功率比(peak to average power ratio,PAPR)、信道适应能力以及低复杂度,但此系统在频谱效率(spectral efficiency,SE)表现上并不理想,系统中的离散傅里叶变换(discrete fourier transform,DFT)扩展和双模调制都有一定的改进空间。针对此系统,提出新的多维索引离散傅里叶变换-扩展正交频分复用(discrete fourier transform-spreading-orthogonal frequency division multiplexing-multi dimension index,DFT-S-OFDM-MDI)系统,新系统将DFT扩展改为DFT索引扩展,增加新的子载波索引位,增加双模调制搭配种类,提升双模索引位宽,进而提升系统SE。本文还为新系统配置6种双模星座图,并与预编码增益矩阵搭配,提升系统误码率(bit error ratio,BER)性能。仿真结果表明,系统具有优秀的SE和BER性能,优于多种传统方案。The dual-mode discrete Fourier transform-spread orthogonal frequency division multiplexing(DFT-SOFDM-DM)system,although possessing many advantages such as excellent peak-to-average power ratio(PAPR),channel adaptability,and low complexity,does not exhibit ideal performance in terms of spectral efficiency(SE).The system's discrete Fourier transform(DFT)spreading and dual-mode modulation can be improved to a certain degree.This paper proposes a novel multi-dimensional indexing discrete Fourier transform-spread orthogonal frequency division multiplexing-multi-dimension index(DFT-S-OFDM-MDI)system,which integrates DFT indexing spreading with dual-mode indexing to form a multi-dimensional indexing system.The new system modifies DFT spreading to DFT indexing spreading,adds new subcarrier index positions,increases the variety of dual-mode modulation combinations,and expands the dual-mode indexing bit width,thus enhances the system SE.Furthermore,the new system is equipped with six types of dual-mode constellation maps and paired with a precoding gain matrix to improve the system's bit error rate(BER)performance.Simulation results indicate that the system has excellent SE and BER performance,outperforming a variety of traditional schemes.

关 键 词：OFDM 频谱效率 星座图 离散傅里叶变换 索引调制 双模调制 预编码矩阵 DFT-S-OFDM 

分 类 号：TN929.52[电子电信—通信与信息系统]