Research On Power Control And Call Admission Algorithms In Heterogeneous Networks

With the rapid development of wireless communication technology,the demand of users has also been on the rise.As a result,there are fewer available wireless physical spectrum resources available.Although there are related spectrum allocation ways to improve spectrum utilization,there is still a static spectrum allocation method currently used,which still has a problem of low spectrum utilization.As a result,cognitive radio technology was born,which abandoned the original spectrum allocation method and shared the spectrum with dynamic spectrum allocation method.In the process of wireless technology development,not only the problem of spectrum shortage exists,but also various emerging wireless access technologies make the interaction between networks more complicated.The complementary features of different wireless access technologies should be utilized,Thus using different wireless technology to seamlessly switch between to provide users with better communication service quality.In view of the above problems,this dissertation makes the following research: Firstly,we study various key technologies in cognitive heterogeneous networks,and summarize the cognitive radio technologies that have arisen due to spectrum shortage.Then we introduce the power control technology,This article summarizes the technology,introduces and compares the technology in detail,and studies the four criteria existing in the technology.It also expounds the principle of game theory,mainly introduces its concept,classification and Nash equilibrium.Heterogeneous wireless networks in call admission control process to consider the main points and its research status quo.Then,this paper focuses on the non-cooperative game power control algorithm in heterogeneous wireless networks.In view of the existing power control problems in cognitive wireless networks,the classical power control algorithm in this field is studied.According to the core idea of this algorithm The non-cooperative game model is established,and the proof of the existence of Nash equilibrium in the model is provided.Finally,the simulation analysis is given on this model.The simulation results show that the power control algorithm balances the transmit power of each cognitive user and improves the effectiveness of the entire system.Finally,this paper proposes a call admission control algorithm,which is based on the premise of ensuring the communication quality of the system,classifies the priorities of user service requests in the system and performs network matching according to the priorities.When the requested resources in the network When the request can not be satisfied,the request will be partially preferentially accessed to the network with the best match.The rest will be matched and transmitted by the session diversion technology according to the high-to-low priority to the network,and the receiver receives each offloading session and sends It performs a merge restore session.In the research process,the use of Markov chain will be complex communication model into a mathematical model for easy research,and in Matlab simulation.The simulation results show that this algorithm guarantees the QoS and reduces the blocking rate of the network when the network arrival rate is high,which improves the resource utilization.