Accurate time delay estimation scheme based on training sequence in OFDM systems

作者：Huang Yi; Hu Aiqun^*; Cheng Yueliang; Xie Shengdong

来源：Journal of Southeast University(Natural Science Edition), 2014, 44(1): 7-11.

DOI：10.3969/j.issn.1001-0505.2014.01.002

• Complexity analysis
• Cross correlations
• Frequency domains
• Low signal-to-noise ratio
• Orthogonal frequency division multiplexing systems
• Sampling frequencies
• Time delay estimation
• Training sequences

An accurate time delay estimation scheme based on training sequence in orthogonal frequency division multiplexing (OFDM) systems is proposed. The scheme employs differential cross-correlation technology to extract the fractional delay in the frequency domain. Then, correlation technology and leading edge method are used to obtain the integer delay after compensation for the fractional delay in the frequency domain. The complexity analysis results show that if the number of searches for estimating the fractional delay is greater than two in the searching method, the computational complexity in the fractional delay estimation of the proposed algorithm is much lower than that of the searching method. The simulation results show that the proposed scheme can achieve an accuracy of decimeter level in the sampling frequency of 10 MHz, the Doppler shift of 222.22 Hz and the number of subcarriers of 1024, which is about 10 dB higher than that of the searching method on average. Moreover, the proposed scheme has a more robust integer delay estimation performance than the traditional correlation technology even at low signal-to-noise ratio (SNR).

• 出版日期2014
• 单位东南大学