Date Added: Feb 2013
Wireless networks can be self-sustaining by harvesting energy from ambient Radio-Frequency (RF) signals. Recently, researchers have made progress on designing efficient circuits and devices for RF energy harvesting suitable for low-power wireless applications. Motivated by this and building upon the classic Cognitive Radio (CR) network model, this paper proposes a novel method for wireless networks coexisting where low-power mobiles in a secondary network, called Secondary Transmitters (STs), harvest ambient RF energy from transmissions by nearby active transmitters in a primary network, called Primary Transmitters (PTs), while opportunistically accessing the spectrum licensed to the primary network. The authors consider a stochastic-geometry model in which PTs and STs are distributed as independent Homogeneous Poisson Point Processes (HPPPs) and communicate with their intended receivers at fixed distances.