| Energy consumption in cellular networks is increasingly a concern, due to the rapid growing demand for mobile communications, the necessity of adding new base stations will continue to grow as well as the amount of energy needed to operate the network. This dissertation presents two algorithms to manage the increasing service demand and create possibilities for energy reduction. The novel cell selection algorithms are bandwidth-based (BB) and energyaware (EA) cell selection. BB balances traffic between two tiers of a LTE heterogeneous network (HetNet) and offloads traffic from high-powered base stations. EA considers the potential energy requirement to serve users and enables turning off base stations during quiet hours. Also, this thesis shows two energy optimization models to minimize the amount of energy consumption in operating LTE HetNets while maintaining levels of customer satisfaction. First, step-dimming (SD) energy reduction technique reduces the transmission power of high-powered base stations according to the levels of traffic demand. Second, resource-based (RE) energy reduction optimization minimizes the spectrum resources required to achieve user service demand level according to the user channel quality indicator (CQI). Last, this dissertation studies benefits of the proposed algorithms in a minimum CAPEX LTE access network in a sample city-like area with time and spatial varying traffic demand.;Keywords: Energy Reduction, HetNet, LTE, Cell Selection. |
