Energy efficient power allocation scheme in heterogeneous cellular networks

The deployment of small-cell access points(SCAs) is widely acknowledged as a promising network densification way to satisfy the future capacity needs of 5G wireless cellular network. In this paper, we study the power allocation problem in heterogeneous downlink network while satisfying QoS constraints and power constraints simultaneously. The scheme is formulated as maximizing the system energy efficiency and then transformed into a tractable convex optimization problem. Utilizing multiflow RZF beamforming to reduce complexity, an iterative algorithm is proposed with provable convergence. Numerical results compare the proposed algorithm in different simulation parameters and show that increasing the number of SCAs, the antennas per SCA and users could enhance the total system energy efficiency.