Base Station Positioning in a WSN with Optimized Energy Consumption

The main problem of the wireless sensor network is energy consumption because there are limited energy resources. In the wireless sensor network the energy consumed in many event sensing, coding, modulation, transmission, reception, and aggregation of data. Data transmission has the highest share in total energy consumption. Data transmission depended on base station location. So the question 'Where the base station should be placed in a two-tiered wireless sensor network field?' has been investigated.