Análise de soluções heurísticas e ótimas para otimização de sistemas WPCN/NOMA com SIC imperfeito e garantias QOS

Abstract

Currently, Brazil and some parts of the world are experiencing the arrival of fifth generation systems, more popularly, 5th Generation (5G), and many efforts have been made to take advantage of network resources. In this context, 5G consists of a network enabled for the deployment of IoT systems (Internet of Things), where a large number of devices will connect to the network wirelessly. Thus, the impact of the growth in the use of wireless communication networks becomes even more evident, which demands the development of studies to optimize network resources. This work shows a simple scenario of a communication system with the objective to formulate a optimization problem to maximize the total data rate in uplink in a WPCN(Wireless Powered Communication Network) that use NOMA (Non-Orthogonal Multiple Access) followed by imperfect SIC (Sucessive Interference Cancelation), with minimum requirements of heterogeneous rates for each user of the system as a way to guarantee QoS (Quality of Service). The scenario developed consist in a communication cell with a BS (Base Station) providing a circular coverage area, establishing link with the users. The system is divided in two fases: The first one occurs in downlink and an energy harvesting is carried out applying concepts of wireless power transfer to recharge the users’s batteries with energy from electromagnetic waves. The second phase occurs in uplink where the multiple access scheme used is NOMA, being necessary apply the SIC with a certain decoding order. This work studies the optimization of the second phase of the modeled WPCN network. In computational simulations performed, a comparative analysis of the results obtained in the optimal solution with three solutions proposed in reference articles is made, where some parameters were varied. The results show that as the minimum rate requirement increases, more infeasible solutions are found and the lower the datarate achieved by users.