Conference Paper

State-of-charge measurement error simulation for power-aware wireless sensor networks

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Abstract

Wireless sensor networks (WSNs) are power critical systems, because they are used in application areas without wired infrastructure. Each sensor node needs a dedicated power supply. Today's protocols and applications for WSNs are often power-aware. However, the state-of-charge (SoC) estimation of the energy storage component (e.g. rechargeable battery) influences the decisions of the power-aware software. A measurement error may cause wrong decisions which would reduce the lifetime of the network. This work presents the simulation results of the impact of an SoC measurement error on the network lifetime running a simple and an enhanced power-aware WSN application. A simulation environment written in SystemC-AMS is used, which enables the combined simulation of the sensor node's application software and its hardware. The simulation shows a reduction of the network lifetime of 3.13% caused by an erroneous measurement. However, the enhanced software is able to increase the network lifetime by 1.66%.

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