Research On Simultaneous Wireless Information And Power Transfer Based On Time Reversal

Nowadays,the communication technology with 5G technology as a core is widely used in various industries such as medical care and energy,for instance,driverless cars,home Internet of Things,and wireless energy-carrying communication.Among them,wireless energy-carrying communication technology is a technology that can gather energy and process signal simultaneously,its application scenarios have become widespread,and its development potential is to be found.However,this also brings about problems such as complicated equipment,more sophisticated processing than traditional communication methods,and increased costs.The core reason is that due to the reduced power intensity of signal processing and energy gathering,a series of operations such as signal amplification and energy consumption reduction are required,and requirements of different scenarios depend on different equipment.The purpose of time reversal technology is to use the focusing capability after its processing to enhance signal intensity.This technology has certain development potential in the field of wireless communication and other fields.Considering the coordination of wireless energy-carrying communication and time reversal,the main contents of this paper are as follows:First,in view of the problems of energy gathering and effective transmission of wireless energy-carrying communication under imperfect channel state information,the impact of characteristics of time reversal under imperfect channel state information on the reliability and effectiveness of multi-user MISO-SWIPT system is analyzed,and on this basis,a joint power allocation optimization model is proposed.To begin with,the TR-SWIPT model is established by taking into account the effect of channel estimation error on signal transmission,and using spatiotemporal focusing characteristics of time reversal technology to enhance the system effectiveness.Then,the TR-SWIPT energy-rate expression containing the channel estimation error is derived,and problems are programmed under the condition of the worst imperfect channel state information.At last,the power allocation model is constructed under the constraints of reliability and effectiveness,and the optimal power allocation factor is obtained through CVX.According to the simulation results,when the system sets the optimal power allocation factor,the scheme proposed in this paper can improve the energy gathering efficiency provided that certain rate of information transmission is ensured,the reliability and effectiveness of the system is improved compared to the traditional MISO-SWIPT system.Second,in view of the problems of energy gathering and information transmission effectiveness of wireless energy-carrying communication technology,the dynamic asymmetric power allocation scheme based on time reversal technology in wireless energy-carrying communication is proposed.To begin with,on the basis of the traditional multiplicative repeater communication model,the spatiotemporal focusing characteristics of time reversal technology are used to make the receiver increase the signal utilization rate.Then,the power distribution optimization model is established,using the asymmetric instantaneous channel gain between relay node and target node to minimize the outage probability of the system,and using Dinkelbach iterative algorithm improved by this scheme.After analysis and simulation,the results show that this scheme can effectively improve the system outage throughput while reducing the system outage probability compared with traditional scheme.