Abstract:
The focus of wireless sensor networks is to
develop low cost sensors with sufficient computing and
communication capabilities to support networked
sensing applications. The emphasis on lower cost led to
sensors that are less accurate and less reliable than their
wired sensor counterparts. Sensors usually suffer from
both random and systematic (bias) problems. Even when
the sensors are properly calibrated at the time of their
deployment, they develop drift in their readings leading
to biased sensor measurements. The drift in this context
is defined as a unidirectional long-term change in the
sensor measurement. Assuming that neighboring
sensors have correlated measurements and noting that
the instantiation of drift in a sensor is uncorrelated with
other sensors and inspired by the resemblance of
registration problem in radar target tracking with the
bias error problem in sensor networks we devise a novel
algorithm for detecting and correcting sensors drifts and
show how it improves the reliability and the effective life
of the network.
