MIMO系统中的迭代时变信道估计

陈东华; 赵睿; 彭盛亮

doi:10.3969/j.issn.1671-7775.2013.02.014

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江苏大学学报（自然科学版） ›› 2013, Vol. 34 ›› Issue (2) : 202-205. DOI: 10.3969/j.issn.1671-7775.2013.02.014

论文

MIMO系统中的迭代时变信道估计

作者信息 +

Iterative timevarying channel estimation for MIMO system

Author information +

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摘要

为了提高时变信道环境中MIMO信道估计的性能,利用KarhunenLoeve基扩展模型(KLBEM)建立MIMO系统中符合期望最大化(EM)算法框架的信号模型,从而得到MIMO时变信道的迭代估计方法．将EM算法应用于MIMO系统中进行迭代信道估计,一方面利用了EM迭代来提高信道估计的性能,另一方面利用了KLBEM基函数的正交性来降低信道估计的运算复杂度．在2×2 MIMO系统下的仿真结果表明:算法经5次迭代即可收敛,而且迭代估计的信道脉冲响应与实际响应几乎重合;此外,迭代估计后系统的BER性能接近理想信道时的BER性能,在高信噪比区域,两者之间的差别在1 dB以内,比最小二乘信道估计有约2 dB的性能增益,可见迭代估计方法在时变信道条件下具有良好的估计性能．

Abstract

Abstract: In order to improve the channel estimation performance for MIMO systems in timevarying channels, a signal model fitting the framework of expectation maximization (EM) algorithm was established based on the KarhunenLoeve basis expansion model(KLBEM). The channel response was estimated in iterative fashion by EM algorithm. In the estimation scheme, the EM iterations and the orthogonality of KLBEM basis functions were introduced to improve the estimation performance and reduce the computational complexity, respectively. The simulation results of 2 by 2 MIMO system show that the proposed scheme convergences after 5 iterations and the estimated channel impulse response is nearly consistent with the actual one. The bit error rate (BER) performance by the proposed scheme is near to that of perfect channel knowledge. At high signal to noise ratio region, the difference between them is lower than 1 dB with 2 dB performance enhancement over the least square channel estimator. The proposed scheme has good estimation performance in timevarying channel conditions.

导出引用

陈东华, 赵睿, 彭盛亮. MIMO系统中的迭代时变信道估计[J]. 江苏大学学报（自然科学版）, 2013, 34(2): 202-205 https://doi.org/10.3969/j.issn.1671-7775.2013.02.014

CHEN Dong-Hua, ZHAO Rui, PENG Sheng-Liang. Iterative timevarying channel estimation for MIMO system[J]. Journal of Jiangsu University(Natural Science Edition), 2013, 34(2): 202-205 https://doi.org/10.3969/j.issn.1671-7775.2013.02.014

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