Research on user fairness of NOMA system for Internet of Vessels
Non-orthogonal Multiple Access(NOMA)technology helps to improve the number of connections and spectral efficiency of Internet of Vessels.This paper studies the energy efficiency optimization of NOMA system under the fairness constraint,designs a user fairness factor based on rate variance,and proposes an energy efficiency optimization strategy of NOMA system with a fairness constraint.Firstly,supposing that the transmission power from the base station to each cluster is the same and the number of users in one clus-ter is fixed,the user clustering scheme is optimized by genetic algorithm with the goal of maximizing energy efficiency.Secondly,the power allocation among users in the cluster is optimized under the condition of meeting the minimum fairness factor.Simulation results show that this optimization strategy can improve en-ergy efficiency and ensure user fairness.