Distributed power control mechanisms in an LTE-advanced system with device-to-device network

Abstract

In this paper, interference mitigation through downlink power control is considered for cellular network based Device-to-Device (D2D) communication. We propose power control schemes, called density based power control (DPC), and region density based power control (RDPC). In the proposed schemes, the transmit power of the D2D sender (D2DS) is based on a simple function of the distance from the macrocell and D2D users' density. The key idea behind the adaptive power control schemes are to adjust the transmit power of the D2DSs so as to just achieve their target data rates for macro user equipments (mUEs). The target rate, in turn, is computed by the network to balance the degradation in macrocell performance. We analyze and compare the two schemes and the conventional fixed power scheme in terms of the system throughput for downlink and outage probability according to the number of D2D receivers (D2DRs). Simulation results show that the RDPC scheme has better performance than the DPC and conventional fixed power scheme performance in terms of the system throughput and outage probability for mUEs.