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浙江大学学报(工学版)
J4  2010, Vol. 44 Issue (4): 681-686    DOI: 10.3785/j.issn.1008-973X.2010.04.010
    
Channel estimation methods for IEEE 802.11n based on
variable tap length
LIU Yunfeng1, CHEN Shumin2, WANG Yang1, PENG Xi1, XU Yuanxin1
1. Institute of Information and Communication Engineering, Zhejiang University, Hangzhou 310027, China;
2. Faculty of Informatics and Electronics, Zhejiang SciTech University, Hangzhou 310018, China
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Abstract  

A method of MIMOOFDM channel estimation based on variable channel impulse response length was presented to improve the WLAN transmission performance for different channel environment. A least squares channel estimation method was investigated with training sequences by adjusting dynamically the tap length and position. Channel estimation with large points was implemented by using the least squares principle to estimate the noise power and determine the noise threshold. Rolloff strategy was applied for the tap length decision, which was based on IEEE 802.11n TGn channel multiple cluster models. Least squares channel estimation using updated tap length was implemented when the threshold was satisfied. Analysis and simulation show that, compared with the traditional MIMOOFDM channel estimation methods, the enhanced method not only saves the system resources, but also improves the estimation performance, especially for the MIMOOFDM systems with high SNR and large constellation.

Published: 14 May 2010
CLC:  TN92  
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Cite this article:

LIU Yun-Feng, CHEN Chu-Min, WANG Xiang, BANG Xi, XU Yuan-Xin. Channel estimation methods for IEEE 802.11n based on
variable tap length. J4, 2010, 44(4): 681-686.

URL:

http://www.zjujournals.com/eng/10.3785/j.issn.1008-973X.2010.04.010     OR     http://www.zjujournals.com/eng/Y2010/V44/I4/681


基于可变抽头长度的IEEE 802.11n信道估计方法

为了提高在不同信道冲激响应长度下无线局域网传输性能,提出一类基于可变抽头长度的MIMOOFDM信道估计方法.该类方法利用训练序列对信道进行估计,动态调整抽头长度及位置,基于最小二乘原理完成一个较大点数的信道估计,估计噪声功率并确定噪声门限.根据IEEE 802.11n无线局域网信道模型中多群集效应,使用消去策略确定需要的抽头长度,在满足门限后对系统进行抽头长度更新后的最小二乘估计.分析及仿真结果表明,该类方法与传统MIMOOFDM信道估计方法相比,节省了系统资源,估计性能有显著提高,尤其适用于较高信噪比及较大星座图调制的MIMOOFDM系统.

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