Algorithm

Engineering

Resource management (computing)

Computational complexity theory

Efficient energy use

Statistics

Computer security

Cognitive radio

Energy (signal processing)

Resource allocation

Telecommunications

Computer science

Energy harvesting

Mathematical optimization

Distributed computing

Integer programming

Computer network

Internet of Things

Mathematics

Artificial intelligence

Heuristic

Wireless

Optimization problem

Resource (disambiguation)

Wireless network

Electrical engineering

IEEE Internet of Things Journal

Cognitive radio (CR) can be leveraged to mitigate the spectrum scarcity problem of Internet of Things (IoT) applications while wireless energy harvesting (WEH) can help reduce recharging/replacing batteries for IoT and CR networks. To this end, we propose to utilize WEH for CR networks in which the CR devices are not only capable of sensing the available radio frequencies in a collaborative manner but also harvesting the wireless energy transferred by an access point. More importantly, we design an optimization framework that captures a fundamental tradeoff between energy efficiency (EE) and spectral efficiency of the network. In particular, we formulate a mixed integer nonlinear programming problem that maximizes EE while taking into consideration of user buffer occupancy, data rate fairness, energy causality constraints, and interference constraints. We further prove that the proposed optimization framework is an NP-hard problem. Thus, we propose a low complexity heuristic algorithm, to solve the resource allocation and energy harvesting optimization problem. The proposed algorithm is shown to be capable of achieving near optimal solution with high accuracy while having polynomial complexity. The efficiency of our proposal is validated through well designed simulations.

Energy Efficient Resource Allocation in EH-Enabled CR Networks for IoT