Title
Novi pristup rešavanju problema frekvencijskog ofseta kod sistema sa ortogonalnim frekvencijskim multipleksom
Creator
Stošović, Slavimir 1981-
Copyright date
2013
Object Links
Select license
Autorstvo 3.0 Srbija (CC BY 3.0)
License description
Dozvoljavate umnožavanje, distribuciju i javno saopštavanje dela, i prerade, ako se navede ime autora na način odredjen od strane autora ili davaoca licence, čak i u komercijalne svrhe. Ovo je najslobodnija od svih licenci. Osnovni opis Licence: http://creativecommons.org/licenses/by/3.0/rs/deed.sr_LATN Sadržaj ugovora u celini: http://creativecommons.org/licenses/by/3.0/rs/legalcode.sr-Latn
Language
Serbian
Cobiss-ID
Theses Type
Doktorska disertacija
description
Datum odbrane: 11.06.2013.
Other responsibilities
mentor
Nikolić, Zorica 1955-
član komisije
Stefanović, Mihajlo
član komisije
Perić, Zoran 1964-
član komisije
Milošević, Vladimir 1952-
Academic Expertise
Tehničko-tehnološke nauke
University
Univerzitet u Nišu
Faculty
Elektronski fakultet
Group
Katedra za telekomunikacije
Alternative title
New approach to the frequency offset problem solving in the system with
orthogonal frequency division multiplex
Publisher
[S. Stošović]
Format
183 lista
description
Biobibliografski podaci: listovi 180-183
description
Telecommunications, application development for mobile devices
Abstract (en)
In this dissertation, principles of orthogonal frequency division multiplex (OFDM), a
method of encoding digital data on multiple carrier frequencies, are given. After theoretical
basics of wireless channel and discrete adaptive filters, advantages and disadvantages of this
kind of transfer are presented. Also, basic blocks of classical OFDM system are described,
with comments on how behavior and implementation of each of them can be improved.
OFDM systems with MDPSK modulation and differential detection in receiver are
considered. Performances for different values of modulation levels and different OFDM
parameter values are analyzed, in accordance with existing standards and OFDM systems that
do not belong to certain standard classification. For this purpose, a modular simulation
environment is developed, in which a universal model of the OFDM system with possibility
of all OFDM parameters adjustment and wireless channel parameters is possible.
The main OFDM system disadvantage is frequency offset sensitivity, which destroys
subcarrier orthogonality and produces intercarrier interference. Hence, frequency offset is the
main factor which limits the subcarrier bandwidth and increase of system bitrate.
In order to resolve frequency offset problem, we analyze OFDM receivers with
different configuration and complexity. Proposed receivers are designed by modifying
existing differential detection algorithms, such as double differential detection, multisymbol
differential detection and decision differential detection algorithm.
The new approach to the frequency offset problem solving in system with orthogonal
frequency division multiplex is based on adaptive transversal filter application. We proposed
optimal OFDM receivers with good performance in wide frequency offset range in the Rician
and Rayleigh fading channel. Proposed receivers significantly improve the quality of the
received signal and can be applied in modern wireless telecommunication systems.
Authors Key words
Bežične komunikacije, Ortogonalni frekvencijski multipleks, Prenos podataka, Feding
Classification
621.391.812(043.3)
Type
Elektronska teza
Abstract (en)
In this dissertation, principles of orthogonal frequency division multiplex (OFDM), a
method of encoding digital data on multiple carrier frequencies, are given. After theoretical
basics of wireless channel and discrete adaptive filters, advantages and disadvantages of this
kind of transfer are presented. Also, basic blocks of classical OFDM system are described,
with comments on how behavior and implementation of each of them can be improved.
OFDM systems with MDPSK modulation and differential detection in receiver are
considered. Performances for different values of modulation levels and different OFDM
parameter values are analyzed, in accordance with existing standards and OFDM systems that
do not belong to certain standard classification. For this purpose, a modular simulation
environment is developed, in which a universal model of the OFDM system with possibility
of all OFDM parameters adjustment and wireless channel parameters is possible.
The main OFDM system disadvantage is frequency offset sensitivity, which destroys
subcarrier orthogonality and produces intercarrier interference. Hence, frequency offset is the
main factor which limits the subcarrier bandwidth and increase of system bitrate.
In order to resolve frequency offset problem, we analyze OFDM receivers with
different configuration and complexity. Proposed receivers are designed by modifying
existing differential detection algorithms, such as double differential detection, multisymbol
differential detection and decision differential detection algorithm.
The new approach to the frequency offset problem solving in system with orthogonal
frequency division multiplex is based on adaptive transversal filter application. We proposed
optimal OFDM receivers with good performance in wide frequency offset range in the Rician
and Rayleigh fading channel. Proposed receivers significantly improve the quality of the
received signal and can be applied in modern wireless telecommunication systems.
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