Does clock precision influence ZigBee's energy consumptions

Abstract

Wireless embedded sensor networks are predicted to provide attractive application possibilities in industry as well as at home. IEEE 802.15.4 and ZigBee are proposed as standards for such networks with a particular focus on pairing reliability with energy efficiency, while sacrificing high data rates. IEEE 802.15.4 is configurable in many aspects, including the synchronicity of the communication, and the periodicity in which battery-powered sensors need to wake up to communicate. This paper develops a formal behavioral model for the energy implications of these options. The model is modularly specified using the language MODEST, which has an operational semantics mapping on stochastic timed automata. The latter are simulated using a variant of discrete-event simulation implemented in the tool MÖBIUS. We obtain estimated energy consumptions of a number of possible communication scenarios in accordance with the standards, and derive conclusions about the energy-optimal configuration of such networks. As a specific fine point, we investigate the effects of drifting clocks on the energy behavior of various application scenarios. © Springer-Verlag Berlin Heidelberg 2007.