Optimal power allocation for energy efficiency maximization in 5G downlink multiuser systems

In this letter, an optimal power allocation scheme for energy efficiency (EE) maximization with low complexity in 5G downlink multiuser systems is presented. The optimal power allocation is obtained in two steps. The first step is to find the power scheme to maximize the geometric mean of weighted average channel gains corresponding to any fixed total dynamic power. The second step to obtain the optimal total dynamic power. Compared with the conventional iterative algorithm, our proposed algorithm can significantly reduce the implementation complexity without sacrificing performance. Monte Carlo simulations show that the proposed power allocation can achieve the EE performance identical to exhaustive search.