Research On Energy Efficiency Of Wireless Body Area Networks Based On Optimal Relay Selection

With the advent of the epidemic era,people pay more and more attention to their physiological health conditions.Wireless Body Area Network(WBAN)is more and more widely used in medical,sports monitoring,military and other fields.At the same time,the traditional medical system is facing great challenges brought by the aging of the world population and the rapid increase of the number of patients with chronic diseases.With the development of wireless communication technology,WBAN is expected to be applied in the medical field to greatly alleviate this dilemma.WBAN is composed of sensor nodes deployed in the body or on the body surface and a sink node.Each sensor node is responsible for monitoring physiological health data of different parts of the body,and the priority of data transmission of sensor nodes varies with medical application scenarios.As a special Wireless Sensor Network(WSN),WBAN has the characteristics of small range,limited energy and dynamic change of network environment,which brings great challenges to the reliability and energy consumption of WBAN communication system.On the one hand,due to the movement of human body,the Quality of wireless channel may be seriously decreased,which will seriously reduce the Quality of Service(Qo S)of communication network.On the other hand,for the sensor nodes partially located inside the human body,in order to increase the comfort of the user,the volume and weight of the sensor are not very large,so that these nodes can only use small batteries as energy sources,resulting in the limited energy of the WBAN.Therefore,on the basis of comprehensive consideration of the priority of data transmission,transmission environment and sensor energy,this paper optimizes the energy efficiency of WBAN,and prolongs the life cycle of wireless body area network while ensuring the quality of network service.Specific innovative work is as follows:Firstly,according to the dynamic changing network environment,combining different sensor nodes to cope with the needs of network changes,a relay node selection method based on logistic regression is proposed.This method takes the priority of data transmitted by sensor nodes,residual energy,location and distance from sink node as characteristic values to select appropriate nodes as relays for WBAN,aiming to provide relay for individual sensor nodes when the network environment is not suitable for direct communication with sink nodes,and improve the service quality of WBAN.The feasibility of this method is verified by MATLAB simulation software.Secondly,the characteristics of WBAN are analyzed,and on this basis,the general modeling of energy efficiency optimization problem of WBAN is carried out.And on the basis of proposing a suitable relay node selection method,the multi-variable optimization problem of energy efficiency optimization of WBAN is transformed into two convex optimization problems of slot allocation and power control.Considering the priority of data transmitted by sensor nodes and the state of environment channel,the working slot of sensor nodes in WBAN is allocated by solving the optimal matching problem.On this basis,the binary method is used to control the transmission power of sensor nodes to optimize the energy efficiency of WBAN.A large number of MATLAB simulation experiments show that the proposed algorithm can effectively improve the energy efficiency of wireless body area network by about 11%.