• KSII Transactions on Internet and Information Systems
    Monthly Online Journal (eISSN: 1976-7277)

Sparsity Adaptive Expectation Maximization Algorithm for Estimating Channels in MIMO Cooperation systems


Abstract

We investigate the channel state information (CSI) in multi-input multi-output (MIMO) cooperative networks that employ the amplify-and-forward transmission scheme. Least squares and expectation conditional maximization have been proposed in the system. However, neither of these two approaches takes advantage of channel sparsity, and they cause estimation performance loss. Unlike linear channel estimation methods, several compressed channel estimation methods are proposed in this study to exploit the sparsity of the MIMO cooperative channels based on the theory of compressed sensing. First, the channel estimation problem is formulated as a compressed sensing problem by using sparse decomposition theory. Second, the lower bound is derived for the estimation, and the MIMO relay channel is reconstructed via compressive sampling matching pursuit algorithms. Finally, based on this model, we propose a novel algorithm so called sparsity adaptive expectation maximization (SAEM) by using Kalman filter and expectation maximization algorithm so that it can exploit channel sparsity alternatively and also track the true support set of time-varying channel. Kalman filter is used to provide soft information of transmitted signals to the EM-based algorithm. Various numerical simulation results indicate that the proposed sparse channel estimation technique outperforms the previous estimation schemes.


Statistics

Show / Hide Statistics

Statistics (Cumulative Counts from December 1st, 2015)
Multiple requests among the same browser session are counted as one view.
If you mouse over a chart, the values of data points will be shown.


Cite this article

[IEEE Style]
Aihua Zhang, Shouyi Yang, Jianjun Li, Chunlei Li, and Zhoufeng Liu, "Sparsity Adaptive Expectation Maximization Algorithm for Estimating Channels in MIMO Cooperation systems," KSII Transactions on Internet and Information Systems, vol. 10, no. 8, pp. 3498-3511, 2016. DOI: 10.3837/tiis.2016.08.004

[ACM Style]
Zhang, A., Yang, S., Li, J., Li, C., , , and Liu, Z. 2016. Sparsity Adaptive Expectation Maximization Algorithm for Estimating Channels in MIMO Cooperation systems. KSII Transactions on Internet and Information Systems, 10, 8, (2016), 3498-3511. DOI: 10.3837/tiis.2016.08.004