  Wireless microsensor networks, which have been the topic of intensive
research in recent years, are now emerging in industrial applications. An
important milestone in this transition has been the release of the IEEE
802.15.4 standard that specifies interoperable wireless physical and medium
access control layers targeted to sensor node radios. In this paper, we
evaluate the potential of an 802.15.4 radio for use in an ultra low power
sensor node operating in a dense network. Starting from measurements carried
out on the off-the-shelf radio, effective radio activation and link adaptation
policies are derived. It is shown that, in a typical sensor network scenario,
the average power per node can be reduced down to 211m mm mW. Next, the energy
consumption breakdown between the different phases of a packet transmission is
presented, indicating which part of the transceiver architecture can most
effectively be optimized in order to further reduce the radio power, enabling
self-powered wireless microsensor networks.
