A SECOND-ORDER CONE PROGRAMMING APPROACH FOR ROBUST DOWNLINK BEAMFORMING WITH POWER CONTROL IN COGNITIVE RADIO NETWORKS
Fulai Liu, Jinkuan Wang, Ruiyan Du, Lu Peng, Pingping Chen · Progress In Electromagnetics Research M · 2011
The downlink beamforiming technology plays a key role in a cognitive radio network (CR-Net). It can be used to reduce transmission power and interference to other users, etc. This paper presents a robust downlink beamforming method with power control for a multiuser multiple-input-single-output (MISO) CR-Net. In this proposed approach, the beamforming optimization problem is formulated as the second-order cone programming (SOCP). The presented method can not only minimize the transmitted power but also guarantee that the received signal-to-interference-plus-noise ratio (SINR) is strictly above the prescribed quality-of-service (Qos)- constrained threshold at each secondary user (SU) and the the interference power (IP) is strictly below the prescribed threshold at the primary user (PU). Simulation results are presented to verify the e-ciency of the proposed method.