OFDM系统中基于lp范数的稀疏信道估计

doi:10.3969/j.issn.1000-436x.2012.z2.036

摘要/Abstract

摘要：

针对已有的基于l₀范数和l ₁范数的LMS算法来实现稀疏信道估计所遇到的问题，引入了新的l_p(0□p□1)范数来替代。通过对l_p范数的分析，选取了最佳的p值为1/2，从而求取最为稀疏的解来实现对信道的估计。在此基础上通过对数据重用方法的使用既节省了训练序列的资源开销，又解决了数据量不足的问题。实验仿真结果表明，在短训练序列条件下，通过与数据重用的方法结合，基于l_p范数的LMS算法与已有方法相比在对稀疏信道进行估计时具有一定的优越性。

关键词: LMS算法, lp(0□p□1)范数, 稀疏信道, 数据重用

Abstract:

The new lp norm was introduced to substitute the l₀ and l₁ norm,as they met some problems when used to estimate sparse channel in LMS algorithm.By analyzing the l_p norm,the optimal value of p was obtained,it was 1/2.Then a most sparse solution could be gotten for channel estimation.And it both saved the cost for training sequence and solved the lack of data size by using data reusing method.Simulation results show that the l_p-LMS performs better than the existing methods,combining with data reusing when the training sequence is certain short.

Key words: LMS algorithm, sparse channel, data reusing

傅剑斌,彭华,董政. OFDM系统中基于l_p范数的稀疏信道估计[J]. 通信学报, 2012, 33(Z2): 250-255.

Jian-bin FU,Hua PENG,Zheng DONG. Sparse channel estimation for OFDM system weighted l_p norm[J]. Journal on Communications, 2012, 33(Z2): 250-255.

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P	时间/s
0.3	0.152 5
0.5	0.113 8
0.7	0.103 3

重用次数L	时间/s
10	0.200 7
30	0.411 5
90	1.061 1