Wireless Powered Cognitive Communications with Asynchronous Channel Access

Abstract

Future machine type networks, such as the Internet of Things (IoT), will be characterized by sporadic transmissions of short packets. In this paper, we study an asynchronous channel access model performed by a primary ad hoc network underlaid with a cognitive secondary wireless-powered ad hoc network. Specifically, we consider that the primary transmitters are connected to the power grid, whereas the cognitive secondary transmitters have radio frequency energy harvesting capabilities and their asynchronous channel access is established based on certain energy and interference based criteria. The sporadic channel traffic is modeled by time-space Poisson point processes and we provide an analytical framework, based on stochastic geometry, for the performance of this asynchronous system.