Power efficient dynamic topology in 3G cellular networks

Green communication aims to reduce the overall energy consumption and to optimize the system capacity. In 3G cellular networks, power consumption of all Node-B´s is same for low traffic time as well as high traffic time. In this paper, power consumption of 3G cellular networks is reduced by forming a power efficient dynamic topology based on Node-B´s. In a 24 hour period, there is certain length of time in which Node-B´s power is underutilized. This time duration is termed as Night Zone and is uniquely defined. During this time, the topology of the Node-B is made dynamic. A single Node-B covers different number of cells in different times based on a sinusoidal rise and fall approximation of the total cell traffic. In this way, the energy, which is used in operating a Node-B, can be saved by shutting down a number of Node-B´s in an area. Our results have shown 37% power being saved in indoor office scenario, 21% in pedestrian environment and 14.8% in vehicular environment. By virtue of a simple analytical model that spans over three distinct environmental scenarios, the behavior of this topology can be generalized for any given environment. The capacity, Quality of Service (QoS), electromagnetic exposure limits and a Node-B´s maximum transmission power constraints are taken into consideration.