Joint Power Allocation and Scheduling Techniques for BER Minimization in Multiuser MIMO Systems

In contrast to the 4G LTE, one of the key requirements of 5G and beyond networks is ultra-high reliability. Towards this end, we investigate the problem of scheduling with joint power allocation for multi-user multiple-input multiple-output (MU-MIMO) systems by taking the reliability into account. In this study, two novel MU-MIMO scheduling methods are proposed based on the use of bit error rate (BER) as the scheduling metric; however, capacity has been typically considered as an user-selection metric in MU-MIMO systems to increase the sum-throughput. In particular, we also develop a new power allocation strategy that can minimize the BER for a given data transmission rate. The computational complexities of the two aforementioned BER-based scheduling algorithms, as well as the conventional capacity-based algorithm, are analyzed. Our simulation results show that the proposed BER-based scheduling algorithms with the joint power allocation have better performance in terms of BER compared to the conventional MIMO scheduling schemes such as a single-user MIMO (SU-MIMO) and the capacity-based scheduling algorithm. The proposed multi-user scheduling framework can be utilized in various emerging applications demanding higher reliability and availability such as mission-critical services.