Throughput Enhancement of Cooperative Spectrum Sensing with Multiple Dual-Polarized Antennas in Cognitive Radio Systems

In cognitive radio (CR) networks, cooperative spectrum sensing is a promising technique that exploits multi-user diversity to mitigate shadowing, fading, and the time-varying nature of wireless channels. In cooperative spectrum sensing, to achieve higher sensing accuracy, more sensing nodes are needed while the throughput of the CR networks is decreased. However, both sensing accuracy and the throughput have significant impacts on the overall system performance. To maximize the throughput with a specific number of sensing nodes that satisfies a constraint for the target sensing accuracy, we propose an efficient cooperative spectrum sensing method that has multiple antennas at each sensing node. Through several simulation results, we demonstrate that the sensing performance of the proposed sensing method is better than that of the conventional cooperative spectrum sensing method. We further extend our work to consider the adverse effect of spatial correlation between neighboring antennas. To reduce this adverse effect on the sensing performance, we also propose the employment of multiple dual-polarized antennas at each sensing node.