student profile: Mr Rui Zhang


Thesis work

Thesis title: Cognitive Radio Network

Supervisors: Yonghui LI , Branka VUCETIC

Thesis abstract:

The performance of wireless communication systems is severely restricted by fundamental constraints on the energy and bandwidth of wireless transceivers. Motivated by this, incorporating wireless energy harvesting into cooperative cognitive radio networks with spectrum sharing has emerged as a promising solution to boost both the network lifetime and spectrum efficiency of future communication systems. We propose and analyze a new full-duplex (FD) cooperative cognitive radio network with wireless energy harvesting. In this novel model, the unlicensed/secondary receiver of the spectrum is equipped with an FD radio and acts as an FD hybrid access point (HAP), which aims to collect information from its associated EH secondary transmitter (ST) and relay the signals. The ST is assumed to be equipped with an EH unit and a rechargeable battery such that it can harvest and accumulate energy from radio frequency signals transmitted by the primary transmitter (PT) and the HAP. We develop a novel cooperative spectrum sharing protocol for the considered system. In the proposed protocol, thanks to its FD capability, the HAP can receive the PT’s signals and transmit energy bearing signals to charge the ST simultaneously, or forward the PT’s signals and receive the ST’s signals at the same time. We derive analytical expressions for the achievable throughput of both primary and secondary links by characterizing the dynamic charging/discharging behaviors of the ST battery as a finite-state Markov chain. We present numerical results to validate our theoretical analysis and demonstrate the merits of the proposed protocol over its non-cooperative counterpart.

Note: This profile is for a student at the University of Sydney. Views presented here are not necessarily those of the University.