Fault-Tolerant Design of Wireless Sensor Networks With Directional Antennas
A tree structure is often used in wireless sensor networks to deliver collected sensor data to a sink node. Such a tree can be built using directional antennas as they offer considerable advantage over the omni-directional ones. A tree is adequate for data gathering from all sensor nodes as long as no node in the tree fails. Since the connectivity of the tree is one, failure of any one node disconnects the tree and may disable the sink node from collecting data from some of the sensors nodes.