Research Of Joint Scheme For Resource Allocation And Relay Selection In SWIPT Cooperative Communication System

The power supply of the wireless communication industry has always relied on batteries and wires.With the advancement of wireless communication technology,the development of the Internet of Things and other industries,and the diversification of mobile terminal devices,traditional energy supply methods are neither convenient nor cause environmental pollution.In order to reduce communication energy consumption,simultaneous wireless information and power transfer(SWIPT)taps energy from wireless RF signals to effectively solve the shortcomings of traditional energy supply methods.The cooperative communication technology guarantees the quality of wireless communication but does not solve the power supply problem of the relay node,which makes the deployment of the relay node difficult and the life cycle of the cooperative communication network is short.Inspired by SWIPT,the cooperative communication and SWIPT are combined to truly realize the green communication target.Therefore,this thesis mainly studies the power resource allocation and relay selection problem in SWIPT cooperative communication system.Due to the multi-objective,the complex solution and the high power resource allocation requirements of the optimization problem,this thesis will solve it through intelligent algorithm.The main work of this thesis is divided into two parts: Firstly,based on the research of two intelligent bionic algorithm,firefly and particle swarm,the analysis of the bionic characteristics of the two algorithms and the principle steps,an improved particle swarm and firefly hybrid algorithm is proposed.By mixing the two algorithms through parallel evolution strategy and then performing nonlinear mixed mutation,not only the advantages of the two algorithms are fully utilized,but also the search performance of the algorithm is improved.The simulation results show that the improved hybrid particle swarm and firefly algorithm proposed in this paper have significant improvement in optimization accuracy,stability and convergence speed performance.Secondly,a scheme for joint optimization of relay node power splitting factor,source node(transmitting node)power allocation factor and relay selection is proposed for the wireless multi-relay cooperative amplifying and forwarding communication network.The global optimization problem is divided into two sub-problems:power resource allocation and relay selection.In the power resource allocation,the improved hybrid particle swarm and firefly algorithm is applied to the power allocation of the source node,and based on the total transmission rate and total power consumption,the power splitting factor of the relay node and the power allocation factor of the source node are jointlyoptimized.Based on the allocation of power resources,a relay selection algorithm based on the expected power threshold is proposed.The simulation results show that the proposed power splitting factor optimization algorithm,power allocation based on improved hybrid particle swarm and firefly algorithm,and relay selection algorithm based on expected power threshold achieve good system performance.The joint optimization algorithm of the three achieves the goal of obtaining a higher total system transmission rate with lower system search and computational complexity and total power consumption of the source node,and improves the energy efficiency of the system.