TY - JOUR
T1 - MMSE based block diagonalization for cognitive radio MIMO broadcast channels
AU - Lee, Kyoung Jae
AU - Lee, Inkyu
N1 - Funding Information:
Manuscript received October 19, 2010; revised April 10, 2011 and July 6, 2011; accepted July 7, 2011. The associate editor coordinating the review of this paper and approving it for publication was G. Colavolpe. This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea Government (MEST) (No. 2010-0017909). The material in this paper was presented in part at IEEE ICC, June 2011. The authors are with the School of Electrical Engineering, Korea University, Seoul, Korea (e-mail: {kyoungjae, inkyu}@korea.ac.kr). Digital Object Identifier 10.1109/TWC.2011.081611.101853
PY - 2011/10
Y1 - 2011/10
N2 - In this paper, we present a linear precoder design for cognitive radio (CR) multi-user multiple-input multiple-output (MU-MIMO) downlink systems where unlicensed secondary users (SUs) can simultaneously utilize the same spectrum used by a licensed primary user (PU). Although a zero-forcing block diagonalization (ZF-BD) precoder is extended to the CR network with the PU, a transmit power boost problem occurs. Therefore, we propose a regularized BD precoder method based on the minimum mean-squared error (MMSE) criteria subject to the interference power constraint under a predetermined threshold for the PU. As a result, the proposed CR-MMSE-BD scheme improves the signal-to- interference-plus-noise ratio at each SU's receiver, compared to the ZF-BD based method. The simulation results demonstrate that the proposed algorithm outperforms the ZF based technique for CR MU-MIMO downlink systems.
AB - In this paper, we present a linear precoder design for cognitive radio (CR) multi-user multiple-input multiple-output (MU-MIMO) downlink systems where unlicensed secondary users (SUs) can simultaneously utilize the same spectrum used by a licensed primary user (PU). Although a zero-forcing block diagonalization (ZF-BD) precoder is extended to the CR network with the PU, a transmit power boost problem occurs. Therefore, we propose a regularized BD precoder method based on the minimum mean-squared error (MMSE) criteria subject to the interference power constraint under a predetermined threshold for the PU. As a result, the proposed CR-MMSE-BD scheme improves the signal-to- interference-plus-noise ratio at each SU's receiver, compared to the ZF-BD based method. The simulation results demonstrate that the proposed algorithm outperforms the ZF based technique for CR MU-MIMO downlink systems.
KW - Cognitive radio
KW - block diagonalization (BD)
KW - minimum mean-squared error (MMSE)
KW - multi-user MIMO
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U2 - 10.1109/TWC.2011.081611.101853
DO - 10.1109/TWC.2011.081611.101853
M3 - Article
AN - SCOPUS:80855147422
VL - 10
SP - 3139
EP - 3144
JO - IEEE Transactions on Wireless Communications
JF - IEEE Transactions on Wireless Communications
SN - 1536-1276
IS - 10
M1 - 6002431
ER -