Research On Device-to-Device Network Access Algorithm Based On Game Theory In Heterogeneous Networks

With the rapid development of portable terminal equipments and diversification of business types,wireless communication technologies have become better.There are many differences between the various types of wireless technologies,and none of these technologies can solely satisfy all the users' requirements.Therefore,the integration of heterogeneous wireless networks is inevitable for future developments in communications.Meanwhile,the method of selecting a suitable network among heterogeneous networks to reasonably utilize wireless resources is a big challenge.To maximize resource utilization and improve the capacity of the communication systems,this thesis focuses on the Device-to-Device(D2D)technology for direct data transmission in heterogeneous networks.The main contents of this thesis are as follows:First,this thesis proposes a network selection scheme among heterogeneous networks for D2 D communications based on game theory.By introducing game theory to quantify and balance business priorities,user states,business requirements and access network parameters,the algorithm uses the analytic hierarchy process to assign the weights of the parameters of each layer,and uses game theory to make overall decisions.This algorithm guarantees user's rate and network load balancing,and avoids unnecessary switching to reduce latency among users.Compared with other classical algorithms,simulation results show that the proposed algorithm dynamically adapts to the changes of network environment and performs better in network throughput and user satisfaction.Second,the thesis studies the interference of D2 D communication underlaying cellular networks with resource sharing mode,and then proposes a D2 D communication power control algorithm based on game theory.In the algorithm,multi-D2 D users who share spectrum resources of cellular users are regarded as gamers,and the utility function is determined.For the user punishment mechanism design,considering the utility and cost,the algorithm enables users to compete and cooperate with each other.By continuously iterating the transmit power,the optimal power response of D2 D links participating in the game is obtained.Simulation results show that under the constraint of pricing factors,game users can choose the appropriate transmit power,which can improve the throughput of D2 D communication.Comparison with other methods shows that this algorithm can effectively improve user fairness.