Context Awareness via GSM Signal Strength FluctuationIan Anderson, Henk Muller, Context Awareness via GSM Signal Strength Fluctuation. the 4th International Conference on Pervasive Computing, Late breaking results. ISBN 3-85403-207-2, pp. 27–31. May 2006. PDF, 70 Kbytes.
In this paper we demonstrate how a cell phone can infer contextual information such as mode of travel by monitoring the fluctuation of GSM signal strength levels and neighbouring cell information. We show that these signals are stable enough to reliably distinguish between various states of movement such as walking, travelling in a motor car and remaining still. We present preliminary results for a metropolitan environment.