Naslov (srp)

Projektovanje višenivoskih konstelacija signala za komunikacione sisteme sa ograničenom snagom: doktorske disertacije

Autor

Vlajkov, Slobodan A.,

Doprinosi

Jovanović, Aleksandra Ž., 1971-
Perić, Zoran
Nikolić, Jelena
Đorđević, Goran
Jakovljević, Nikša

Opis (srp)

In modern digital communication systems, a huge amount ofdata is transmitted, so that research aimed at achieving moreefficient transmission is necessary, which makes the topic of thisdoctoral dissertation relevant and important. The subject ofresearch in this doctoral dissertation is how to improve the powerefficiency of multilevel PAM (Pulse Amplitude Modulation) andAPSK (Amplitude Phase Shift Keying) constellations inpower-limited communication systems, such as opticalcommunications, satellite communications, wirelesscommunications, multiple-input multiple-output systems.A constellation is defined by the geometric-space partition andprobabilities of constellation points. Therefore, under constellationdesigning or constellation shaping the methods that optimizemodulation format by adjusting the geometric-space locationand/or probabilities of constellation points are assumed. All thesemethods are categorized within three constellation shapingschemes: geometric constellation shaping, probabilisticconstellation shaping and hybrid probabilistic-geometricconstellation shaping.Constellation shaping has been usually performed byoptimizing some metric that characterize a channel or byoptimizing the minimum Euclidean distance. Instead of this, in thisdissertation constellation shaping is performed by applyingdesigning techniques from quantization theory. Namely, theexistence of similarity in the geometric-space representation ofconstellation and quantization motivates us to apply thequantization designing methods in constellation shaping.Special attention is paid to reducing the constellationcomplexity, that is to designing the piecewise-uniformconstellations in terms of the geometric-space partition andprobability distribution of constellation points. Methods fordesigning constellation inspired by piecewise-linear compandingquantization have been proposed. Also, a novel designing conceptthat employs the companding technique in constellation shapingon a totally different manner has been proposed.Power efficiency is the ability of a modulation technique topreserve the fidelity/quality of digital data at low values of thesignal-to-noise ratio, and is expressed as the signal-to-noise ratioper bit required to achieve a given error probability. In thedissertation we deal with designing power-efficient multilevelconstellations for channels dominated by the additive whiteGaussian noise, and the metric for constellation performanceevaluation is a functional dependence of symbol error probabilityon signal-to-noise ratio per bit for uncoded constellation in channelwith additive white Gausssian noise. The accuracy of analyzes andachieved results has been verified by performing simulations.

Opis (srp)

Biografija autora: list 113,Bibliografija: listovi 108-112. Datum odbrane: 05.11.2021. Telecommunications

Jezik

srpski

Datum

2021

Licenca

Ovo delo je licencirano pod uslovima licence
Creative Commons CC BY-NC-ND 3.0 AT - Creative Commons Autorstvo - Nekomercijalno - Bez prerada 3.0 Austria License.

http://creativecommons.org/licenses/by-nc-nd/3.0/at/legalcode