Optimized power control strategy in Massive MIMO for distributed IoT networks

Abstract

We study a power control strategy for a Massive MIMO enabled IoT system to increase total throughput and to provide better differentiated levels of service to different classes of IoT devices. We use a closed-form signal-to-interference plus noise ratio (SINR) of Massive MIMO and apply the Lagrange multiplier procedure to find the optimum power control coefficients. We investigate several scenarios which include various cell radii and radiation power levels, and verify that the proposed scheme is effective in increasing total throughput and in providing different levels of throughput to different classes of IoT devices. We also apply the power control scheme when each device’s throughput is aggregated from multiple single-antenna access terminals based on the grouping of devices, and compare the cases when the grouping is conducted before and after power control. We show that grouping before power control can provide better differentiated levels of services by allocating different power to each group, while grouping after power control always provides higher total throughput by jointly considering all IoT devices.