On the Feasibility of Network RF Energy Operated Field Sensors

This paper estimates the feasibility of operating field sensors using otherwise unwanted radio frequency (RF) energy in a wireless ad hoc sensor network. In the traditional concept, an exposed node is kept from any communication activities during a neighbor´s transmission. To save energy, the node may go to sleep mode during its inactivity period. In contrast, it is proposed that whenever a node is not communicating it should attempt to collect energy from the ongoing transmissions in its vicinity. A two-tier network is considered with the field sensor nodes having rudimentary communication (transmission) functionality at the first tier and the routing-capable nodes at the second tier. Via geometric probabilistic analysis, aided by network simulations, the conditions on rectification efficiency and transmission duty cycle of network RF energy operated field nodes are derived for their uninterrupted processing and transmission activities.