Joint Data and Pilot Power Control Algorithm for Weighted Sum SE in Uplink Single-Cell MU-Massive MIMO Systems

摘要

This paper consider the joint data and pilot power control problem in uplink single-cell multi-user massive multiple-input-multiple-output (MU-Massive- MIMO) systems. Instead of using equal data and pilot power allocation among each user equipment (UE), in this paper, we formulate the power control as an optimization problem for weighted sum spectral efficiency (SE) maximization objective subject to per-user pilot and data power budget in the uplink. To this end, we derive a lower bound expression on the average uplink SINR with maximum ratio combination (MRC) receiver under imperfect channel knowledge. Since the optimization of weighted sum SE has been proved to be a NP-hard problem, we propose an efficient algorithm to obtain an approximated optimal solution with polynomial complexity, by joint iterative optimization over data power and pilot power for each UE. The convergence of the proposed algorithm is guaranteed and discussed. Numerical results demonstrate the optimality of the proposed algorithm and show notable SE performance gains over suboptimal algorithms in previous work.