摘要
针对传统的正交频分复用(OFDM)信号的带宽估计方法在低信噪比多径信道下,估计精度低且计算量大的问题,提出一种OFDM信号带宽盲估计方法.本方法首先根据接收到的观测信号建立自回归(AR)模型,通过AR模型计算信号的功率谱;然后将其功率谱等效成矩形谱,并将矩形谱的带宽作为OFDM信号的估计带宽;最后通过多次循环求统计平均得到信号的精确带宽估计.仿真结果表明:本方法在GSNR=0dB的多径信道下,带宽估计仅为1.68%.可见在低信噪比多径信道下该方法的带宽估计精度更高,计算复杂度更低.
Traditional orthogonal frequency division multiplexing（OFDM） bandwidth estimation scheme can not achieve accurate estimation results at low signal noise ratios（SNRs） and in multipath channels,besides,it acquires a great mount of computation.To deal with these problems,a new bandwidth estimation scheme of OFDM signals was proposed.Firstly,the autoregressive（AR） model was established according to the received OFDM signals,and the power spectrum density could be computed with the AR model.Secondly,the power spectrum density was equivalent to a rectangular spectrum whose bandwidth was used as the bandwidth of OFDM signals.Finally,it was repeated many times and the statistical average value was used as the final bandwidth estimation value.Simulation results show that bandwidth estimate scheme with estimation error has only 1.68% at GSNR=0 dB and in multipath channels.So the new scheme not only has higher precision at low SNR and in multipath channels but also has lower computational complexity.
出处
《华中科技大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2011年第10期79-82,共4页
Journal of Huazhong University of Science and Technology(Natural Science Edition)
基金
国家高技术研究发展计划资助项目(2007AA01Z288)
国家自然科学基金资助项目(60772138)
高等学校学科创新引智计划资助项目(B08038)
关键词
正交频分复用
参数估计
带宽估计
多径信道
自回归模型
矩形谱
orthogonal frequency division multiplexing（OFDM）
parameter estimate
bandwidth estimate
multipath channels
autoregressive（AR） model
rectangular spectrum
