Date of Award
1-1-2018
Document Type
Dissertation
Degree Name
Ph.D.
Organizational Unit
Daniel Felix Ritchie School of Engineering and Computer Science, Electrical and Computer Engineering
First Advisor
Mohammad Matin, Ph.D.
Second Advisor
Vijaya Narapareddy, Ph.D.
Third Advisor
Ronald DeLyser
Fourth Advisor
Wenzhong Gao
Keywords
OFDM, Orthogonal frequency division multiplexing, Optical, Patch antenna, W-LAN, Wireless local area network
Abstract
The advantages of optical fiber make it possible to extend the data rate transmission and propagation distance. Orthogonal frequency division multiplexing (OFDM) as a multicarrier technique (MC) is used in hybrid optical-wireless system designs because it has the best spectral efficiency to radio frequency (RF) interference and lower multipath distortion. In this dissertation, a study and evaluation of optical OFDM based wireless local area network (W-LAN) systems are presented. The baseband of the OFDM signal is fully transmitted and up-converted to a radio frequency signal. Also, to reduce system costs, simple base stations (BSs) are interconnected to a central office (CO) via an optical fiber. All the required operations are achieved in the CO. The directly modulated laser (DML) and continuous wave (CW) laser are used in the system simulations as optical laser sources. Identical rectangular microstrip patch antennas have been used at the transmitter and the receiver as well. The simulations were carried out for different SMF and MMF lengths, and the variable wireless distance between the transmitting and receiving antennas was in a range of 40 dB to 80 dB.
The purpose of this work is to provide a framework for integrating wireless and optical technologies in one system with the presence of OFDM technology. The required microstrip patch antenna parameters for the system are analyzed and designed. The microstrip patch antenna (S-parameters) is loaded into the Optisystem communication software tool in Touchstone format. As a result, this achievement gives a greater impetus to design an integrated optical-wireless system, and simulation results validate the proposed technique.
Then, the integration of the microstrip patch antenna and optical OFDM system is achieved, and the performance is intensely studied. The entire system has been presented by developing analytical models and simulations.
The system performance results are obtained regarding EIRP, SNR, signal constellations and BER. The results show that this integrated optical wireless link is very robust for carrying OFDM based wireless LAN signals over an optical fiber. Moreover, using an active patch antenna in the system helps to increase the coverage service to more than 30 meters when an SMF of 80 km length is utilized.
Publication Statement
Copyright is held by the author. User is responsible for all copyright compliance.
Rights Holder
Salih Mohamed S. Kenshil
Provenance
Received from ProQuest
File Format
application/pdf
Language
en
File Size
122 p.
Recommended Citation
Kenshil, Salih Mohamed S., "Study of Optical OFDM System for Wireless LAN Applications" (2018). Electronic Theses and Dissertations. 1426.
https://digitalcommons.du.edu/etd/1426
Copyright date
2018
Discipline
Optics, Communication