Battery-less sensor nodes for 802.15.4/ZigBee wireless networks

Abstract

Battery-free wireless sensor nodes are very convenient in many applications. They eliminate the costs associated with installing batteries and reduce maintenance headaches. For these reasons, they are gaining in popularity. Such devices usually require the use of an energy source that harvest power from the surroundings. Because of the necessity of harvesting energy and the related costs, there are limitations to the kind of application and wireless protocol that can successfully be implemented, especially when energy is produced intermittently. The interest in 802.15.4-based wireless systems such as ZigBee has also led to its consideration for battery-less nodes. In this paper we briefly discuss some of the challenges faced when using 802.15.4/ZigBee in applications where little energy is available. We then show that some of the recently introduced microcontrollers featuring FRAM memory allow interesting gain in energy, making it even easier to overcome the difficulties.