计算机工程与应用 ›› 2009, Vol. 45 ›› Issue (9): 21-23.DOI: 10.3778/j.issn.1002-8331.2009.09.006

• 博士论坛 • 上一篇    下一篇

全相位OFDM系统子载波间干扰的性能分析

孙山林1,2,侯春萍1,阎 磊1   

  1. 1.天津大学 电子信息工程学院,天津 300072
    2.桂林航天工业高等专科学校,广西 桂林 541004
  • 收稿日期:2008-11-03 修回日期:2008-12-01 出版日期:2009-03-21 发布日期:2009-03-21
  • 通讯作者: 孙山林

ICI performance analysis for all phase OFDM systems

SUN Shan-lin1,2,HOU Chun-ping1,YAN Lei1   

  1. 1.Tianjin University,Tianjin 300072,China
    2.Guilin College of Aerospace Technology,Guilin,Guangxi 541004,China
  • Received:2008-11-03 Revised:2008-12-01 Online:2009-03-21 Published:2009-03-21
  • Contact: SUN Shan-lin

摘要: OFDM是下一代无线通信的关键技术之一,而载波频率偏移会使OFDM的子载波失去正交性,同时给系统带来载波间干扰,引起系统性能严重下降。针对这一情况,提出利用全相位FFT来解决频偏问题。全相位FFT利用自身的频谱分析功能来实现对信号相位和振幅的判决。经理论证明它的相位没有误差,能降低噪声功率,且由频偏引起的子载波间的干扰远小于常规OFDM系统,同时振幅和频率通过全相位频偏估计器的校正可以得到弥补。最后,通过实例仿真验证了该系统的BER性能是高于现有的OFDM系统。

关键词: 正交频分复用, 全相位快速傅里叶变换, 载波频率偏移, 子载波间干扰

Abstract: Orthogonal Frequency Division Multiplexing(OFDM) is one of the key technologies for the next wireless system.However,frequency offsets ruin the orthogonal in sub-carriers and cause inter-carrier interference(ICI).A novel all phase OFDM(APOFDM) system is proposed.APFFT is introduced to overcome ICI aroused by carrier frequency offset(CFO).This scheme makes use of APFFT signal processing and frequency domain coding to reduce the amount of ICI generated as a result of CFO,with little additional computational complexity.At the same time,the proposed system has zero phase error.It is proved to be correct and effective in mathematics.The simulation results indicate that APOFDM system has a better performance than conventional OFDM system.

Key words: Orthogonal Frequency Division Multiplexing(OFDM), all phase Fast Fourier Transform, carrier frequency offset(CFO), inter-carrier interference(ICI)