Thesis Defense - Sara Ghasvarianjahromi (MSEE)

Sara Ghasvarianjahromi – M.Sc. Electrical and Eectronics Engineering

Prof. Murat Uysal– Advisor

Date: 27.07.2021

Time: 17:00

Location: This meeting will be held ONLINE. Please send an e-mail to gizem.bakir@ozyegin.edu.tr in order to participate in this defense.

Simultaneous Lightwave Information and Power Transfer in Underwater Visible Light Communications

Thesis Committee:

Prof. Murat Uysal, Özyeğin University

Asst. Prof. Kadir Durak, Özyeğin University

Asst. Prof. Bahattin Karakaya, Istanbul University

Abstract:

In this thesis, we investigate simultaneous lightwave information and power transfer (SLIPT) for underwater visible light communication systems. We consider four SLIPT methods namely AC-DC separation (ADS), time switching (TS), power splitting (PS) and time switching-power splitting (TS-PS) where the splitting/switching factors are defined as optimization parameters in TS, PS and TS-PS methods. For each of these methods, we derive closed-form expressions for the average harvested energy, bit error rate and spectral efficiency in the presence of underwater turbulence modeled by lognormal statistics. Using these expressions, we determine the optimal splitting factors to maximize the harvested energy while satisfying a given bit error rate value and a given threshold spectral efficiency value. Our results reveal that, if not optimized, SLIPT methods under consideration are outperformed by the simple AC-DC separation (ADS) method which provides the largest harvested energy versus spectral efficiency (HE-SE) region. Optimization of splitting/switching factors extends the HE-SE regions; hence, optimized versions of TS, PS and TS-PS methods are able to significantly outperform ADS for most cases. We further investigate the effect of various channel and system parameters such as water type, turbulence level, beam divergence, receiver aperture size on the harvested energy and quantify the improvements in battery lifetime through the use of SLIPT methods.

Bio: 

Sara Ghasvarianjahromi (Student Member, IEEE) received the B.Sc. degree in electrical and electronics engineering from the Islamic Azad University of Science and Research of Fars, Shiraz, Iran in 2013. She had been a member of the WINEL Research Lab at Yazd University, Yazd, Iran between 2014-2017.  She is currently working toward the M.Sc. degree in communication systems engineering with the Communication Theory and Technologies (CT&T) Research Group at the Ozyegin University, Istanbul, Turkey under the supervision of Professor Murat Uysal.  Her current research interests include optical wireless communications, wireless power transfer, optimization algorithms, and energy harvesting.