OFDM无线系统载频与定时偏移估计算法

针对受到传播时延、多普勒效应以及发送端与接受端振荡器的不匹配等因素影响的正交频分复用OFDM(orthogonal frequency division multiplexing)无线系统载频与定时偏移问题,提出了一种基于周期稳态性的载频与定时偏移估计算法CSBE(cycloslationary based estimation).该算法通过对接收信号的周期稳态性及相关性估测出频率偏移与时隙偏移,进而有效地提高OFDM系统抗频率与定时偏移的能力.仿真实验以及与现有BE算法的性能比较表明,提出的频率与定时偏移估计算法在加性高斯白噪声AWGN(additive white Gaussian noise)与瑞利衰落信道下都明显地减小了频率与定时偏移误差.

Carrier frequency and timing offsets estimation algorithm in OFDM wireless systems

Because of the problem of f requency and timing of f sets caused by pro paga tion delay , Doppler effect and the mismatch betw een sending and receiv ing oscillator in OFDM wi reless sy stems, a f requency a nd timing of fsets estima tion algo ri thm based o n cyclostationa ry cal led CSBE w as proposed. The algo ri thm estimated frequency a nd timing of fsets for cy clo statio nary and co rrelatio n to improv e the abi li ty o f anti-f requency a nd timing o ff set s. Simulation and compa rison result s prov e that the proposed CSBE algo ri thm decreases the erro rs o f f requency a nd timing o ff set s in AWGN and Rayleig h-fading channels.