An accurate energy model for wsn node and its optimal design

Different from the traditional wireless networks, in wireless sensor networks(WSNs), power consumption is a critical aspect, because current nodes are always supported by constrained-energy battery. A particular challenge in maintaining extended battery lifetime lies in achieving communications with low power. For better understanding of the design trade offs of WSNs, a more accurate power consumption model for wireless sensor node is proposed. Different from models ever showed, in which the power consumption of each component in WSN node was assumed constant , the new one takes into account energy dissipation of circuits in practical physical layer. It shows that there are some parameters such as data rate, carrier frequency, RF output power et al, which have a significant effect on the WSN node with the metric energy per useful bit (EPUB). Then an optimal design method to make the network energy efficient is described by adjusting one or more of these parameters. The efficiency of the strategy was validated by mathematical analysis and simulations. The results showed that the EPUB can be reduced by optimally choosing the rate-power combination based on the proposed power consumption model for a given load .