A robust and energy efficient cooperative spectrum sensing scheme in cognitive radio networks

In a cognitive radio network, cooperative spectrum sensing is usually implemented to achieve higher detection accuracy than single user sensing. However, the performance of cooperative spectrum sensing is destructively impaired, when the reporting and inter-user channels both inevitably experience fading besides the detecting channel in reality. To solve this problem, we propose a robust scheme, called dynamic multi-head selection based cooperative spectrum sensing scheme. Our scheme utilizes both the multi-user selection diversity and the inter-user transmission error comparison jointly, to reduce the transmission error of sensing messages over fading channels. Meanwhile, our scheme is also designed to save the total transmit energy efficiently during its execution. This benefit is due to the hierarchical reporting manner and the adaptive transmit power option adopted in our scheme. Simulation results show that the sensing performance and energy efficiency can both be improved significantly by our scheme.