Optimizing Performance Of Heterogeneous Coexisting Wireless Networks For Smart Healthcare

Nowadays,with the rise of 5G,Io T and AI,the concept of smart healthcare has gradually entered people’s vision,and Medical Io T plays an important role in smart healthcare.However,the explosive growth of the types and number of medical Io T devices has made the open wireless frequency bands for medical equipment more and more crowded,and at the same time,the conflict caused by the coexistence of heterogeneous wireless networks has become frequent,leading to performance degradation and fairness problem.In order to solve the problem of fairness and throughput performance degradation in heterogeneous wireless coexistence in the smart medical scenario,this thesis focuses on LAA-WiFi coexistence network and takes throughput performance optimization under fairness constraint as the main research problem.First,this thesis analyzes the characteristics and application requirements of LAA-WiFi coexistence network in smart medical scenarios,and based on that,this thesis proposes a theoretical model for LAA and WiFi coexistence network in medical scenarios.Comparing to Bianchi Model,which is widely used to analyze this problem,explicit expressions of throughput and probability of successful transmission can be obtained through theoretical derivation of the network using our model.The explicit expressions can intuitively show the relationship between network performance and heterogeneous network parameters and effectively reduces the computational complexity.Based on theoretical and simulation results,we find that the initial backoff window and the holding time of successful transmission have the obvious impact on the performance of network throughput.Second,this thesis explaines,quantifies and enhances the principles of time fairness and 3GPP fairness from a theoretical perspective.And this thesis proposes two optimization theorems under time fairness constraint and 3GPP fairness constraint,respectively,which both give the explicit expressions of maximum throughput and the best initial backoff window.These two theorems achieve the goal of maximizing coexistence network throughput under fairness constraints with low computational complexity.Theoretical and simulation results show,the coexistence network under the current standard settings cannot guarantee fairness,and has low throughput performance in some scenarios.And the coexistence network under the optimal settings that this thesis proposed,can guarantee fairness and stable throughput performance,which is above 0.9(normalized).Third,this thesis considers smart hospital,and proposes adaptive optimization architecture for coexistence of wireless networks in smart hospitals based on software defined wireless network(SDWN).This thesis also proposes solutions for parameter collection and distribution applied to this architecture.The architecture proposed in this article has good compatibility and scalability.And the solutions mainly use virtual APs in SWDN and WiFi beacon frame,which will make very small changes to current equipment.The solutions have high feasibility and ecological compatibility.Based on the optimized architecture and solution,the optimization theorem proposed in this thesis can be easily deployed to practical network.In the end,work in this thesis addresses the challenges of heterogeneous wireless coexistence in smart medical scenarios from the perspective of fair coexistence and performance optimization of LAAWiFi coexistence network.Simulation results show that the problems of fairness and throughput performance degradation caused by the coexistence of heterogeneous wireless network can be effectively solved from the model and optimization theorem proposed in this thesis.At the same time,the work in this thesis can also be extended from smart medical scenarios to other scenarios,providing guidance for the future integration and optimization of 5G heterogeneous networks.