Power Allocation Mechanism in Uplink NOMA Using Evolutionary Game Theory

Abstract

The rapid advancement in communication systems and Internet of Things (IOT) has increased the demand for high data rates, reliability, better Quality of Service (QoS), and reduced interference. As the upcoming 5G aims to accommodate more number of users in the limited available spectrum, Non-Orthogonal Multiple Access (NOMA) outperforms the accommodation of users on the channels. In this paper, an algorithm to optimize the uplink power allocation of the user pairs in NOMA for the two-user system model is discussed. Typically, NOMA uses same frequency slot, same time slot, but different power levels to transmit user’s data, resulting in higher spectral efficiency. Successive interference cancellation is the major challenge in this scheme, which is enhanced with proper selection of power levels at which the users transmit the data. The optimum power allocation in NOMA can be modeled as a game in which Evolutionary Game Theory (EGT) helps the Base Station (BS) to provide the best optimal power level for the user pair to transmit their message signals simultaneously on the same channel under the profound channel conditions and position of that user pair in the cell. It is shown that EGT is a successful tool in deciding power levels of participating mobile stations.