Lazy Calibration for Wireless Sensor Networks

Sensor networks are designed to monitor an area but their sensors notoriously suffer from poor accuracy. Although these sensors could be manually calibrated or replaced with precise alternatives, the time, manpower, and monetary costs may be prohibitive. Further, environmental changes may require regular re-calibration, adding to the expenses previously mentioned. We propose a method for lazily calibrating mote sensors to reduce sensor network deployment costs. Our approach uses the entire sensor network to calibrate motes dynamically and does not require explicit routing schemes or maintained links. As a result, our approach does not depend on any specific nodes and packet collisions, wireless networking irregularities and mote failures will cause minimal impact in the sensor network. In this paper, we demonstrate up to 4x reductions in sensor error by using a computationally inexpensive algorithm for low power mote processors while requiring only a small fraction of pre-calibrated motes.