中国邮电高校学报(英文) ›› 2009, Vol. 16 ›› Issue (2): 1-7.doi: 10.1016/S1005-8885(08)60192-2

• Wireless •    下一篇

Synchronization of MIMO OFDM systems by perfect complete generalized complementary orthogonal loosely synchronous code groups

王键,杨讯,李道本   

  1. School of Information Engineering, Beijing University of Posts and Telecommunications, Beijing 100876, China
  • 收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:2009-04-30
  • 通讯作者: 王键

Synchronization of MIMO OFDM systems by perfect complete generalized complementary orthogonal loosely synchronous code groups

WANG Jian, YANG Xun, LI Dao-ben   

  1. School of Information Engineering, Beijing University of Posts and Telecommunications, Beijing 100876, China
  • Received:1900-01-01 Revised:1900-01-01 Online:2009-04-30
  • Contact: WANG Jian

摘要:

This article proposes a time/frequency synchronization algorithm in the multiple input multiple output (MIMO) systems, in which the perfect complete generalized complementary orthogonal loosely synchronous code groups are used as the synchronization sequence. The synchronization algorithm is divided into four stages: 1) synchronization in time domain by signal autocorrelation; 2) synchronization in frequency domain by fast Fourier transform (FFT); 3) multipath dissociation using coherent detection and fine time synchronization; 4) fine frequency offset estimation by phase rotation. As per the perfect complete generalized complementary orthogonal loosely synchronous code groups, the cross-correlation and out-of-phase auto-correlation for any relative shift between any two codes is always zero. This ideal property makes the time/frequency synchronization algorithm simple and efficient. The simulation results show that even in the multipath fast fading channel with low signal noise ratio (SNR), the MIMO system can get synchronized both in the time domain and frequency domain with high stability and reliability.

关键词:

MIMO,;OFDM,;synchronization,;complementary;orthogonal;code,;loosely;synchronous;(LS);code

Abstract:

This article proposes a time/frequency synchronization algorithm in the multiple input multiple output (MIMO) systems, in which the perfect complete generalized complementary orthogonal loosely synchronous code groups are used as the synchronization sequence. The synchronization algorithm is divided into four stages: 1) synchronization in time domain by signal autocorrelation; 2) synchronization in frequency domain by fast Fourier transform (FFT); 3) multipath dissociation using coherent detection and fine time synchronization; 4) fine frequency offset estimation by phase rotation. As per the perfect complete generalized complementary orthogonal loosely synchronous code groups, the cross-correlation and out-of-phase auto-correlation for any relative shift between any two codes is always zero. This ideal property makes the time/frequency synchronization algorithm simple and efficient. The simulation results show that even in the multipath fast fading channel with low signal noise ratio (SNR), the MIMO system can get synchronized both in the time domain and frequency domain with high stability and reliability.

Key words:

MIMO;OFDM;synchronization;complementary orthogonal code;loosely synchronous (LS) code