Research On Wireless Information And Power Transfer Based On Multi-point Classified Wbans

Wireless Body Area Networks(WBANs),as a branch of the Internet of Things(IoT),have become an important part of smart medical and smart wearable system.WBANs are based on the human body and belong to low-power wireless sensor networks(WSNs),which are composed of miniature wireless sensors implanted in the body or distributed on the surface of the body.WBANs are widely used in health care,military operations,sports training and entertainment.Especially in medical rehabilitation and major disease prevention,it has the most development prospects.It can use telemedicine services to monitor various physiological information of the human body,diagnose diseases,and even assist doctors in treatment.WBANs can not only improve the level of modern medicine,but also improve the efficiency and quality of medical services,which is of great significance.In order to ensure the safety of human body,sensors in WBANs are generally small,low power and limited in battery capacity and even some are inconvenient to replace in the body.Therefore,energy efficiency is a major problem in the researches of WBANs.As an active wireless energy transmission method,wireless energy harvesting technology has become one of the effective ways to solve the problem of continuous energy supply for multiple sensors.However,the introduction of this technology has also brought new challenges to WBANs,which leads to the complicated network resource structure and the prominent resource allocation problem.Especially in a WBAN with multiple sensors,each sensor is connected to each other and restricts each other.Therefore,how to ensure the efficiency of WBANs through reasonable resource allocation is one of the most important research directions at present.In order to ensure the continuity and stability of information transmission,the combination of direct and relay transmission is essential.Considering the energy causality of sensors and the relay,this paper builds a multi-point classified wireless body area network with the cooperative transmission model,and proposes a power allocation algorithm based on maximum ratio combining(MRC).The research of WBANs' resource allocation brings forward new ideas.The main research ideas are as follows: first,based on the distribution of sensors on the human body,a wireless energy and information cooperative transmission model based on multiple sensors is established.The MRC transmission protocol based on power allocation is used to get the maximum transfer rate.Secondly,to further improve the existing model,a classified wireless energy and information transmission model is proposed,and mathematical formulas are derived for the two stages of energy collection and information transmission.Finally,numerical simulation and theoretical analysis are performed on the proposed algorithm and model through simulation experiments,and its superiority is verified in and under different circumstances.The main research work of this paper is as follows:Firstly,cooperative transmission was introduced,and a multi-point WBAN with energy and information cooperative transmission model was established.The relay node was between the sensor node and the source node.According to the position of each sensor and the model of WBANs' channel,the corresponding path loss and channel gain are obtained.Secondly,considering the cooperation relationship and transmission possibility between the sensor node and the relay node,combining the protocol of energy collection and information transmission with the MRC protocol,an MRC transmission protocol based on power distribution is proposed.Third,with the energy causality and the total system power as the constraints,a maximum throughput model is constructed,and an algorithm for MRC transmission optimization based on power allocation is derived,including establishing the related mathematical model.The algorithm is optimized and the simulation proves the effectiveness of the proposed algorithm.Fourth,improve the existing transmission model and propose a classified WBANs energy and information transmission model.Taking the maximum information transmission rate as the optimization goal,the simulation results are used to compare the advantages and disadvantages of the two algorithms and verify the feasibility of the protocol.In the above research,the proposed energy harvesting and information transmission protocol based on multi-point classified WBANs is discussed and analyzed in detail,aiming to solve the problem of power allocation in multi-point wireless body area networks with limited energy causality between sensor nodes and relay nodes.This paper theoretically solves the resource allocation problem in multi-sensor node wireless body area networks,realizes the adaptive power allocation of the relay and sensors,improves system throughput and network reliability,and proposes new ideas for the future research of WBANs.