On the use of selection function in cooperative MISO at wireless sensor network

Energy efficient data transfer is the key factor for the design of energy efficient wireless sensor network (WSN). IEEE 1451.5 standard explores the wireless communication schemes between multiple sensors and a data gathering node (DGN) emphasizing the multiple input single output (MISO) structure. Sensors participating in this MISO can be chosen selectively for more energy efficient data transfer and the selection is controlled by several parameters which are not completely explored yet. In this paper, an energy efficient cooperative technique is proposed for a WSN where selected numbers of sensors are used to form a MISO structure wirelessly connected with a DGN. The selection of nodes is based on a selection function which is a combination of channel condition, residual energy, inter sensor distance in a cluster and geographical location. Data are sent by the sensors to a DGN using a multihop transmission. We are concentrating our design on the final hop where sensors transmit their data to the DGN. A mathematical model is developed to get the selection function.