Energy-efficient pilot and data power allocation in massive MIMO communication systems based on MMSE channel estimation

This paper addresses the pilot and data power allocation issue in time division duplexing (TDD) massive multi-user multiple-input multiple-output (MU-MIMO) systems. By using minimum mean square error (MMSE) channel estimation along with a maximum-ratio combining (MRC) detector for the uplink transmission and a maximum-ratio transmission (MRT) precoder for the downlink transmission, a novel pilot and data power allocation scheme is proposed to minimize the total uplink and downlink transmit power under per-user signal to interference-plus-noise ratio (SINR) and power consumption constraints. The main contribution of this paper lies in formulating the original energy efficient power allocation problem and converting such a complicated optimization problem to a geometric programming one. Computer simulation shows that the proposed scheme can save up to 78% of the total power as compared to the equal power allocation among all the mobile users.