Computing geometric median to locate the sink node with the aim of extending the lifetime of wireless sensor networks

In case of wireless sensor networks (WSNs) the sensed data which are collected by the ordinary senor nodes will have to be forwarded to the sink node (Base Station) in order to be accessible by the remote users. The location of the sink could significantly affect the energy dissipation and throughput of the network. This paper aims to investigate an optimal location for the sink node in such a way that the sum of distances from all the sensor nodes to the sink node is minimized. In an effort to place the sink node within the network our algorithm finds the geometric median of all the location associated with the sensor nodes. In a discrete set of points, the geometric median could be defined as the location which basically minimizes the sum of distances to all the points. Performance evaluation reveals that the proposed location for the sink node extends the network lifetime comparing with other possible location within the network field.