An Energy-Efficient Optimization Algorithm Based on Cross-layer Design for Cognitive Radio Networks

In order to increase the energy efficiency of secondary users in cognitive radio networks, the processes of spectrum sensing and access of secondary users are modeled by continuous-time Markov theory. Based on the analysis of the main factors affecting the energy efficiency of secondary users, an energy-efficient algorithm based on cross-layer design is proposed. The algorithm can decrease communication interruption probability of secondary users caused by unslotted access of primary users, and a tradeoff between sensing performance and energy effi-ciency is gained by setting proper sensing time and access probability. Simulation results indicate that the proposed algorithm is better than single-layer optimal schemes which only consider either spectrum sensing or access strategy for it provides the secondary users with more energy efficiency.