Joint Optimal Beamforming and Sensing Interval design for Energy Efficient Cognitive Small Cell
Guangyue Lu, Yujiao Ma, Boyang Liu, Yuxi Qiang, Fuhui Zhou · 2018
We consider a cognitive small cell to improve both energy efficiency and spectral efficiency. The goal of this paper is to jointly optimize the spectrum sensing time, spectrum sensing interval and the beamforming matrix to maximize the energy efficiency of the small cell. A non-convex optimization problem is formulated under the primary user interference constraint, the secrecy rate constraint and the energy harvesting constraint. The non-convex problem is transformed into a concave problem and a Dinkelbach's method based iterative algorithm is used to obtain the optimal solution. Simulation results show that the proposed algorithm leads to a significant improvement of the energy efficiency than the traditional spectrum sensing scheme.