Efficient spectrum discovery with energy constraints in cognitive radio networks
Yi Liu, Rong Yu, Shengli Xie, Yan Zhang, Victor C. M. Leung · 2011
Cognitive Radio (CR) is an essential technique for the future generation green communication paradigm owing to its inherent advantages of adaptability and cognition. The compulsory spectrum sensing is a critical component to facilitate systems co-existence. In this paper, we propose a new Time-Division Energy Efficient (TDEE) sensing scheme in which the sensing period is divided into an optimal number of timeslots and each Secondary User (SU) is assigned to detect a different channel in one time-slot. An important advantage of TDEE is that the SUs do not need to exchange the control messages for the acknowledgement of a successful cooperation, leading to substantial energy saving without compromising sensing accuracy. Both homogeneous and heterogeneous networks are investigated with respect to the intrinsic trade-off between spectrum efficiency and energy-efficiency. Illustrative results demonstrate that the proposed TDEE is able to achieve much lower energy consumption compared to the existing mechanisms.