Research On Resource Optimization Algorithm Based On Power Control In D2D Assisted Cellular Networks For Mobile Health

Mobile health(m-health)is a new health care model based on mobile communication technology refers to the use of mobile communication technology to provide medical information services.It can improve the efficiency of medical services and reduce the consumption of human resources.When building a mobile medical network,it is necessary to consider the scarcity of network spectrum resources caused by the increase of the number of users in the future.In order to solve this problem,device-to-device(D2D)communications technology has emerged.It can potentially increase system spectral-efficiency(SE)and device energy-eff-iciency(EE),also help to solve the problem of lack of spectrum resources.This thesis takes this as the background to study the related problems of power control.Power control,as a key technology to optimize network resource allocation,help to reduce the interference of signals and improve the networks'capacity.But the research of power control in m-health scene will have more restrictive conditions,in comparison with traditional power control methods.In this thesis,under the background of mobile medical scene and D2D multiplexing network,the related problems of power control are studied.The main work is as follows:(1)considering the sensitivity of medical equipment to EMI,it is necessary to limit the transmission power of the user.In order to solve this problem,we constrain it as a subsequent optimization algorithm.Then,under the restriction of EMI,we discuss the problem of energy efficiency optimization based on user priority,and then propose a power control algorithm based on energy efficiency optimization.In the process of solving,because of the complexity of solving the problem with constraint conditions,we use the penalty function method to simplify the solving process of the problem,and prove that the algorithm converges in the optimal energy efficiency.(2)The game theory and nash equilibrium in the potential game theory is studied.According to the particularity of the mobile medical scene,a game model of the corresponding power control is set up.The wireless users in the network are regarded as the players of the game.Because each user is rational and private,want to get bigger power than others,in other words,to make the highest utility.Based on this,the optimal reactive dynamics power control algorithm is proposed,and it is proved that the algorithm converges to a unique Nash equilibrium in the game.(3)Considering the situation of imperfect channel state information between user communication in mobile medical scene,CSI error will reduce the performance of network wireless resource allocation,and bring a certain degree of waste to network resources.We studied on CSI.Then,on the basis of EMI constraints and imperfect CSI,the optimization of individual energy efficiency is modeled and a power control algorithm based on imperfect CSI is proposed.The aim is to optimize the distribution of transmit power to maximize the utility of the user.Then the mathematical deduction of game theory is used to prove that the algorithm will converge to the only Nash equilibrium.Finally,the three algorithms are experimentally verified,and the convergence and effectiveness of the algorithm are compared with other algorithms.The experimental results show that the proposed algorithms can control the EMI in an acceptable range and achieve robust performance,which can significantly improve the energy efficiency of the network or the user's personal utility.