Abstract
In K-user multiple-input multiple-output (MIMO) interference channels, it was shown that interference alignment (IA) achieves a full spatial multiplexing gain when perfect channel state information (CSI) is available at each transmitter in the network. When the CSI is fed back from receivers using the limited number of feedback bits, a significant performance loss is inevitable in the IA due to quantized channel knowledge. In this paper, we propose a new channel quantization strategy to optimize the performance of the IA with limited feedback. In our proposed scheme, we introduce an additional receive filter to minimize the chordal distance which accounts for the quantization error on Grassmann manifold. Besides, we analyze a reduction in terms of the chordal distance in our scheme compared to conventional methods. Simulation results verify that the proposed scheme provides substantially better performance than the conventional method as the number of feedback bits is increased. We show that our scheme exhibits 30% and 40% sum rate gains compared to the conventional scheme when the numbers of the feedback bits are 10 and 15, respectively, with two antennas per node.
Original language | English |
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Article number | 6092791 |
Pages (from-to) | 358-366 |
Number of pages | 9 |
Journal | IEEE Transactions on Wireless Communications |
Volume | 11 |
Issue number | 1 |
DOIs | |
Publication status | Published - 2012 Jan |
Bibliographical note
Funding Information:Manuscript received May 2, 2011; revised September 11, 2011; accepted October 20, 2011. The associate editor coordinating the review of this paper and approving it for publication was D. Huang. This work was supported in part by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (No. 2010-0017909), and in part by a Korea University Grant. The authors are with the School of Electrical Engineering, Korea University, Seoul, Korea (e-mail: {jinsungkim, shmoon, sangrim78, inkyu}@korea.ac.kr). Digital Object Identifier 10.1109/TWC.2011.111211.110810
Keywords
- Interference alignment
- channel quantization
- limited feedback
ASJC Scopus subject areas
- Computer Science Applications
- Electrical and Electronic Engineering
- Applied Mathematics