Research On Energy Trading Method Based On Wireless Power Transfer In Cooperative Relaying Network

Cooperative communication technology can effectively improve the reliability and transmission rate of communication systems by obtaining diversity such as time and space.When the channel quality from the sender to the receiver is poor,the information transmission performance can be improved by using the cooperation of the relay node.In the communication system,many nodes rely on batteries for power supply.Once the energy in the batteries is exhausted,the nodes cannot continue to work.The wireless charging technology can use radio frequency(RF)signals as a carrier for energy collection,and is not limited by the defects in the collection environment.An energy supply point(ESP)is arranged around the communication node for wireless power supply,which can provide stable energy for the communication node and can effectively extend the service life of the communication node.This paper combines wireless charging technology with cooperative communication technology,and uses the ESP around the network to provide relay nodes with energy.Considering that the energy supply point ESP is not selfless,without incentives,they are unwilling to provide energy at no cost,and need to obtain a certain reward when providing energy to the relay node.We combine the Starkellberg theory and contract theory to design energy trading methods,and provide reasonable incentives under the conditions of symmetric and asymmetric information,so that ESP can provide stability to relay nodes under certain rewards.Reliable energy to maximize system benefits.The main work and results of this article are as follows:(1)We propose a wireless power supply energy trading method based on Starkellberg theory.In this method,the interaction process between ESP and the destination node is modeled as a non-cooperative game process,and the ESP and the destination node serve as the model in the model.Leader and follower.Specifically,the destination node,as the leader,pays a certain amount of remuneration to the ESP,and maximizes its utility by optimizing the remuneration paid to the ESP.As a follower,ESP provides a certain amount of energy to the relay node,and maximizes its own utility by optimizing the energy provided.We study how the method optimizes the compensation paid by the destination node to the ESP and the energy provided by the ESP to the relay node under the conditions of symmetric and asymmetric information,and finds an optimal equilibrium point so that both the destination node and the ESP can obtain the maximum Benefits,while maximizing the overall social welfare.Simulation results show that the proposed method can effectively improve the system speed compared with the case without relays.(2)In order to further improve the system performance in the case of information asymmetry,we propose a contract based wireless power supply energy trading method,in which the interaction process between ESP and the destination node is modeled as a labor market like model.The destination node is the employer and the surrounding ESP is the employee.ESP provides labor(i.e.energy)to the relay node to help transfer the information of the source node,and then obtain the corresponding return provided by the destination node.The destination node will find a suitable ESP contract to start the transaction.The constraints of ESP personal rationality and incentive compatibility are introduced to ensure that participation in transactions will not affect their own performance.ESP divides different types according to its personal information,and feeds back information to the destination node.Each ESP selects a contract based on its type.We study the contract design problem in the case of information symmetry and asymmetry,and obtain the corresponding rewards of the power received by the optimal relay node from the ESP and the energy provided by the destination node to the ESP,so as to achieve the goal of maximizing social welfare.In the case of information asymmetry,some hidden information of ESP can be obtained by signing the target node of the contract process,so as to alleviate the information asymmetry.Moreover,the constraints of contract theory make ESP unable to select contract pairs at will.Compared with Stackelberg theory,it can reduce system consumption cost and maximize social welfare,and improve system performance.The simulation results show that compared with Stackelberg's theory,the contract theory makes the social welfare of the whole system more obvious.