Research On Power Control Of Mobile Network Under Medical EMI Restriction

Medical problems and people's quality of life are closely related,which has always been the focus of attention.Mobile health(m-health),a new health care model based on mobile computing,medical sensing and communication technology,and provisde the medical services through the application of mobile communication technology.The development of m-health has brought an effective solution to optimize the allocation of medical resources,improve medical efficiency and quality,reduce the cost of treatment.Research based on mobile medicine has been paid more and more attention currently?Therefore,this thesis discusses the power control problem in the background of mobile health.As one of the key technologies for optimizing the allocation of network resources in communication systems,power control can reduce the mutual interference of the signals in the system and maximize the system capacity.Compared with the traditional power control research,the power control research in the m-health scene has different characteristics and restrictions.There is a critical problem with the use of wireless communications in mobile medical scenarios where The radiation of the signal will produce electromagnetic interference(EMI)to the medical sensor,and the interference degree will increases as the communication transmit power increases,and high levels of electromagnetic interference can cause serious failure of the medical sensor.Based on the electromagnetic sensitivity of medical sensors,how to control the power resources to achieve the optimal allocation of network resources can also ensure the normal work of medical sensors,which is the main problem in this thesis.In the power control process,because the users in the wireless network are selfish,each user tends to maximize their performance by increasing power,but this increase in power will cause interference to other users in the network,and too much power will bring harmful medical equipment EMI.As a mathematical theory to solve the conflict of interest,game theory can be used to analyze the power control problem because the power control process and the game process are very similar in different scenarios.How to use game theory to solve the above conflict problem is the key of this thesis.Based on the m-health background and CDMA system as an example,we propose two power control algorithms in the framework of non-cooperative game theory to schedule data transmission.The local power control algorithm uses a joint power and rate control algorithm based on classic game theory to maximize the utility of each wireless user constrained by electromagnetic interference.The global power control algorithm,based on the optimal return principle of the potential game theory for dynamic scheduling method,which aims to guide each user to achieve network-level optimization(near-optimal)under the premise of minimizing electromagnetic interference.Finally,we have simulated the two algorithms respectively.The data show that the two algorithms can effectively control the electromagnetic interference in the acceptable range.In this paper,our local power control algorithm can converge to the unique Nash equilibrium,which can achieve robust performance against the variations of mobile health environments.Compared with the existing algorithms,the proposed global power control algorithm has an improvement of 8% in network performance.