Chapter 3
Energy Efficiency of Geographic Opportunistic Routing
Wireless sensor networks (WSNs) are characterized by multihop lossy wireless links and severely resource-constrained nodes. Among the resource constraints, energy is probably the most crucial one since sensor nodes are typically battery powered and the lifetime of the battery imposes a limitation on the operation hours of the sensor network. Unlike the microprocessor industry or the communication hardware industry, where computation capability or the line rate has been continuously improved (regularly doubled every 18 months), battery technology has been relatively unchanged for many years. Energy efficiency has been a critical concern in wireless sensor network protocol design. Researchers are investigating energy conservation at every layer in the traditional protocol stack, from the physical layer up to the network layer and application layer.
Among the energy consumption factors, communication has been identified as the major source of energy consumption and costs significantly more than computation in WSNs (Pottie and Kaiser 2000). Opportunistic routing has shown its advantage on energy efficiency (Zeng et al. 2007; Zorzi and Rao 2003) comparing to traditional routing. However, the existing opportunistic routing schemes like GeRaF (Zorzi and Rao 2003) typically include all the available next-hop neighbors as forwarding candidates, which does not lead to optimal energy efficiency.
In this chapter, we propose an ...
