Base station placement and network topology may be key factors affecting the lifetime of wireless video sensor networks, according to Thomas Hou and Scott Midkiff, who recently received a $225,000 NSF Information Technology Research (ITR) grant to study and improve video sensor network lifetime. The ITR program funds about 10 percent of all submitted proposals.
"A major challenge with a wireless video sensor network is maximizing the lifetime of the network given that there is limited battery power at each node and that replacing or recharging the batteries is usually not feasible," Hou said. "An analysis of power dissipation at the nodes suggests that wireless communication consumes significantly more energy than any other node activity," he added. "Thus, if we can optimize the communication power consumption behavior of the sensor node, we can extend the network lifetime."
The team is exploring several definitions for network lifetime, taking into account the percentage of nodes required to remain alive and the different priorities of nodes based on their locations. The researchers are studying base-station placement and multihop routing, base-station placement constraints, and dynamic varying network topology.
"We have found that the techniques and algorithms from the field of computational geometry can help us understand the problem, study the impact of topology control, and develop performance bounds needed for this research," Hou said.
After determining topology control techniques, the team will develop a software toolkit that can be used by sensor network designers to optimally perform network topology control.