Research On Handoff Management Mechanism And Algorithm In Dense Networks

Dense network is an important trend in the fifth generation mobile communication system,but also a key technology.With the dense deployment of various low-power small base stations in the network,the network structure becomes extremely complicated and high-efficiency network capacity is increased,which brings great challenges to the network handoff management.Therefore,how to realize the seamless handoff of users in dense networks Management mechanism and energy efficiency mobility management are the hot topics of 5G mobile communication system.To this end,this paper focuses on handoff management mechanism and algorithm in dense network,the main contents are as follows:1.Research on handoff management mechanisms based on small base station controlDense networks enhance space reuse by means of encryption and deployment of small base stations.In order to solve the increase of handoff interruption delay,signaling and data forwarding consumption by frequent handovers in small cells.In this paper,we propose a handoff management mechanism based on small cell controller.The scheme first proposes two handoff procedures according to the design network architecture to reduce handoff signaling,data forwarding consumption and handoff interruption delay;Secondly,construct the discrete-time Markov transfer model to evaluate the performance of the proposed handoff procedures,and introduce a connected-inactive state in 5G new air interface as the start and end of session.Calculate the stationary distribution and formulate the average cost function for each switching consumption and interruption delay during the user session.The simulation results show that the proposed handover mechanism can reduce handoff costs compared with the current 3GPP handoff scheme,and lower handover interruption delay can be achieved.This scheme is of great significance for the study of 0 millisecond interrupt latency in the demand of 5G New Radio(NR).2.Research on handoff decision algorithm base on energy consumptionA large amount of energy consumption problem can be caused by frequent handoff between small base stations in dense networks.In order to achieving 5G green communications.In this paper,a handoff management algorithm based on constrained Markov decision process(CMDP)model is proposed to minimize the energyconsumption of base stations while guaranteeing the quality of service of user.Firstly,the scheme constructs a Markov states transition model in which channel states and user speeds are states on discrete time slots to capture the influence of the random behavior of handoff parameters on the optimization objectives.Secondly,during the entire service flow,the state transition probability is calculated based on the state space and the action space,and a desired function of the base station side energy consumption generated by the sum of the immediate reward function sequences is constructed.In the CMDP,the expected function of the energy consumption of the base station in the service period of the UE is minimized and the transmission delay and call-dropping rate are guaranteed to meet certain constraint conditions.The optimal handoff strategy is obtained by using the combination of Lagrange method and value iteration.The simulation results show that the handoff strategy algorithm can reduce the total system energy consumption.