Adaptive Wavelet Filtering for Data Enhancement in Wireless Sensor Networks

Ehsan Sheybani

Virginia State University, Petersburg, USA.

DOI: 10.4236/jst.2012.22012                

Abstract

Noise (from different sources), data dimension, and fading can have dramatic effects on the performance of wireless sensor networks and the decisions made at the fusion center. Any of these parameters alone or their combined result can affect the final outcome of a wireless sensor network. As such, total elimination of these parameters could also be damaging to the final outcome, as it may result in removing useful information that can benefit the decision making process. Several efforts have been made to find the optimal balance between which parameters, where, and how to remove them. For the most part, experts in the field agree that it is more beneficial to remove noise and/or compress data at the node level. We have developed computationally low power, low bandwidth, and low cost filters that will remove the noise and compress the data so that a decision can be made at the node level. This wavelet-based method is guaranteed to converge to a stationary point for both uncorrelated and correlated sensor data. This is mainly stressed so that the low power, low bandwidth, and low computational overhead of the wireless sensor network node constraints are met while fused datasets can still be used to make reliable decisions.

Keywords

Wavelet Transform; Wireless Sensor Networks; Noise; Order Reduction; Fusion

Conflicts of Interest

The authors declare no conflicts of interest.

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