Research on Base Station Sleeping Mechanism of User Connections in Ultra Dense Network

On the basic of traditional macro cellular networks, ultra dense networks deploy plenty of low-power nodes working with maximum power, which provide superior communication quality and produce more energy consumption in networks. Aiming at the problem of wasting network resources caused by low-power nodes during low-load period in ultra dense networks, we study a kind of base station sleeping mechanism based on user connections. When the network loads are low, the connections between users and base stations (BSs) are sensed by environment awareness technology. Then, the connection relationship is used to establish a connection matrix. After that we use the established connection matrix to build a weighted bipartite graph. Taking the users’ QoS and the load of BSs into account, we build a weight matrix by weighting the two as the weights of the bipartite graph. We get the optimal connection between users and base stations by constantly optimizing the value of the connection matrix. By modeling, we transform the optimization problem into a 0–1 integer programming problem and get the optimal connection by Particle Swarm Optimization algorithm. Finally, the sleeping mechanism is executed according to this connection matrix, and we achieve the goal of energy conservation by closing low-load BSs.