Spectrum Sensing Method Based on Cognitive Radio in LTE Systems

A spectrum sensing method in the femtocell of long time evolution (LTE) system is proposed. In this method, the femtocells sense the uplink spectrum via energy sensing and discover the active macrocell users through two-steps decision spectrum sensing method. The femtocells identify the traffic types of these active macrocell users and adjust the sensing period according to different traffic types to implement the tradeoffs between throughput and sensing overhead of femtocells. Simulation results indicate that this method can improve the femtocell throughput and system performance when the interference to macrocell users and sensing overhead are effectively controlled.