Transmit Beamforming in MIMO Cognitive Radio Network via Semidefinite Programming

Transmit beamforming is designed for multiple-input multiple-output (MIMO) cognitive radio network in which single primary user (PU) coexists with single secondary user (SU). The proposed cognitive beamforming minimizes the transmit power of the SU while limiting the interference temperature to PU and achieving the signal-to-interference-plus-noise ratio (SINR) target at SU. With perfect knowledge of channel information and receive beamforming pattern of the PU, the optimization problem is formulated as quadratically constrained quadratic programming (QCQP), and the optimal solution is obtained by using semidefinite programming relaxations (SDR). A probabilistic approach is developed by guaranteeing the interference temperature below a pre-specified threshold with high probability for the case when no knowledge of receive beamforming vector of the PU is available at the SU transmitter (SU-Tx). Simulation results demonstrate the effectiveness of the proposed approach in both scenarios.

[1]  Nikos D. Sidiropoulos,et al.  Spectrum Sharing in Wireless Networks via QoS-Aware Secondary Multicast Beamforming , 2009, IEEE Transactions on Signal Processing.

[2]  Yonina C. Eldar,et al.  Robust Downlink Beamforming for Cognitive Radio Networks , 2010, 2010 IEEE Global Telecommunications Conference GLOBECOM 2010.

[3]  Ying-Chang Liang,et al.  Exploiting Multi-Antennas for Opportunistic Spectrum Sharing in Cognitive Radio Networks , 2007, IEEE Journal of Selected Topics in Signal Processing.

[4]  Leandros Tassiulas,et al.  Joint optimal power control and beamforming in wireless networks using antenna arrays , 1998, IEEE Trans. Commun..

[5]  Marius Pesavento,et al.  Iterative dual downlink beamforming for cognitive radio networks , 2010, 2010 Proceedings of the Fifth International Conference on Cognitive Radio Oriented Wireless Networks and Communications.

[6]  Holger Boche,et al.  Solution of the multiuser downlink beamforming problem with individual SINR constraints , 2004, IEEE Transactions on Vehicular Technology.

[7]  Ying-Chang Liang,et al.  Robust Downlink Beamforming in Multiuser MISO Cognitive Radio Networks With Imperfect Channel-State Information , 2010, IEEE Transactions on Vehicular Technology.