**Author details**

24 Wireless Sensor Networks / Book 1

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of energy replenishment is greater than the rate of consumption. In this case, the network is

This chapter presented the smart routing protocol for large-scale networks that enables for the deployment of wireless sensor networks (WSNs) in geographically distributed locations of interest. Smart routing is based on performance measure and energy optimization using cross-layer considerations of the protocol stack. We presented the performance improvement of smart routing over minimum power routing in these distributed networks to illustrate the benefit of the smart routing protocol for enabling next-generation commercial applications. By doing so, we also presented the impact of application criticality on performance and network lifetime. Applications that have high performance demands require greater resources and, as a result, have shorter network lifetimes; energy-conserving systems, on the other hand,

We also covered energy harvesting and its impact on resource allocation. We determined that, since sensors are able to operate at peak performance as long as sufficient resources are available, energy harvesting enables us to maintain this level of performance for a longer period of time. If the replenishment rate *rh* is greater than or equal to the consumption rate *rc*,

• **Software Radio Modeling**: Quantify the impact of packet conversion on energy reserves for multiple technologies including WiMax, WiFi, Ultrawideband (UWB) and Zigbee; • **Distributed Source Coding (DSC)**: Design algorithms to reduce the amount of data that is routed from sensor networks based on the compression of multiple correlated sensor measurements. In this manner, energy may be conserved while maintaining performance; • **Sensor Localization**: Design sensor localization methods that are either triangulation-based or use a third-tier of nodes in the network, such as anchors, for

Future research shall explore a number of areas to further the smart routing protocol:

allocate resources to prolong network lifetime at the expense of performance.

the network is self-sustaining and can theoretically survive on its own.

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r h =0 r h =22 μW

r h =25 μW

r h =30 μW

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(b) Energy Harvesting with Rate *rh* for a UWB Sensor

212 Wireless Sensor Networks – Technology and Protocols Cross-Layer Design for Smart Routing in

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**Figure 13.** Energy Dissipation and Impact of Energy Harvesting

(a) Energy Dissipation with Rate *rc*

self-sustaining and can theoretically last forever.

**12. Conclusions and future research**

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Sheikh Omar M. and Mahmoud Samy A.

*Faculty of Engineering and Design, Department of Systems and Computer Engineering, Carleton University, Ottawa, Canada*
