摘要
In this paper, a novel robust precoder with imperfect channel state information(CSI)is proposed for multi-input multi-output(MIMO)cognitive multiuser networks equipped with relays. In the proposed model, the secondary users(SUs)are allowed to share the spectrum with the primary users(PUs)when the interference temperature(IT)is below a specific threshold. The transmitting strategy of relays is amplify-and-forward(AF), and the CSI error is characterized in terms of spherical uncertainty region. A minmax problem for the transmit power of the relays is considered when the mean square error(MSE)of SUs and the IT of PU meet their corresponding thresholds, and it is transformed into a semi-definite programming(SDP)problem to search for the solution. Numerical simulations demonstrate the effectiveness of the proposed precoder.
In this paper, a novel robust precoder with imperfect channel state information（CSI）is proposed formulti-input multi-output（MIMO）cognitive multiuser networks equipped with relays. In the proposed model, thesecondary users（SUs）are allowed to share the spectrum with the primary users（PUs）when the interference temperature（IT）is below a specific threshold. The transmitting strategy of relays is amplify-and-forward（AF）, and theCSI error is characterized in terms of spherical uncertainty region. A minmax problem for the transmit power of therelays is considered when the mean square error（MSE）of SUs and the IT of PU meet their corresponding thresholds,and it is transformed into a semi-definite programming（SDP）problem to search for the solution. Numericalsimulations demonstrate the effectiveness of the proposed precoder.
基金
Supported by the Beijing Key Laboratory of Work Safety Intelligent Monitoring(Beijing University of Posts and Telecommunications)
关键词
天津大学学报
英文版
cognitive radio
multi-input multi-output
imperfect channel state information
semi-definite programming
robust precoding
