Intelligent Beamforming To Enhance The Secondary User Performance

Abstract: Cognitive radio assents the secondary users to access the spectrum of the primary user only when there is a spectrum hole is detected. Hence the looked-for spectral competence cannot be achieved. To improve the spectral efficiency the synchronicity of the primary and secondary users are required and it is achieved by beam forming. Two main problems are existing while beam forming are to achieve the throughput required by the secondary user and to maintain the interference level below the threshold value. The problems are solved by using convex optimization technique and SVD. By using the SVD single channel can be spliced into orthonormal channels; because of that coexistence of primary and secondary users can be implemented and the steering vector is used to improve the directionality of the signal. MIMO system with four antennas is considered for simulation. Using the new proposed scheme it is sure that the MIMO cognitive radio performance will be enhanced.

Keywords: Cognitive radio, Beam forming, SVD, Convex Optimization.