Wireless sensor networks, a special type of wireless ad hoc networks, consist of large numbers of wireless sensor nodes. The idea of a wireless sensor network is to achieve the same sensing quality as a remote sensing system by utilizing a large number of wireless sensor nodes to perform close-range sensing. Wireless sensor nodes are compact communication devices that can virtually fit in anywhere. They are battery-powered devices that can greatly reduce deployment overheads due to wirings. To ensure a terrain of interest is fully covered, usually more than enough wireless sensor nodes are deployed to provide redundant sensing coverage. With a proper onoff scheduling scheme, the total energy consumption of a network can be reduced without introducing significant impacts to its target detection capabilities. In this chapter, two bio-inspired scheduling schemes are revisited. In both schemes, wireless sensor nodes can decide to operate in different operation modes dynamically. The decisions are made based on local information. Performances of a network can be fine-tuned by adjusting the behaviours of the nodes in their mode decisions.

Chapter Contents:

• 19.1 Introduction
• 19.2 Related work
• 19.3 Scheduling scheme for WSNs based on social insect colonies
• 19.3.1 Biological phenomena
• 19.3.2 Mechanisms
• 19.4 Scheduling scheme for wireless sensor networks with co-operative transmissions
• 19.4.1 Co-operative diversity
• 19.4.2 Mechanisms
• 19.5 Simulation
• 19.5.1 Simulation settings
• 19.5.2 Simulation results
• 19.6 Discussion
• 19.7 Future developments
• 19.8 Conclusion
• Appendix A
• References

Inspec keywords: scheduling; sensor placement; object detection; ad hoc networks; wireless sensor networks

Other keywords: wireless ad hoc sensor network; remote sensing system; wireless sensor node deployment; target detection; on-off scheduling scheme; bioinspired scheduling scheme; mode decision; battery powered device; redundant sensing coverage

Subjects: Wireless sensor networks