Kvaliteta audio usluge u VOIP sustavima

scientific master's theses

• Title (english): Audio Service Quality in VoIP Systems
• Author: Krešimir Crnković
• Mentor: Hrvoje Domitrović (mentor)
• Committee member: Siniša Fajt (predsjednik povjerenstva)
• Committee member: Hrvoje Domitrović (član povjerenstva)
• Committee member: Tino Bucak (član povjerenstva)
• Granter: University of Zagreb; Faculty of Electrical Engineering and Computing; (Department of Electroacoustics); Zagreb
• Defense date and country: 2011-11-24, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Electrical Engineering
• Universal decimal classification (UDC): 621.3 - Electrical engineering

Abstract

Prijenos govora IP mrežama svojevrstan je izazov današnjim komunikacijama. Od nekadašnjih tradicionalnih PSTN sustava prijenos govora je kroz VoIP dosegao jednu posve novu dimenziju. Osim telekomunikacijskih tehnologija tu se isprepliću i druge tehnologije i aspekti karakteristični za njih. Tu se prvenstveno misli na signalizacijske metode, obradu govora kao audio signala, sigurnosne i ekonomske aspekte njegovog korištenja te na kraju brigu o uspostavi kvalitete usluge kao temeljnog zahtjeva na VoIP sustave. Općenito su predstavljene dobrobiti korištenja VoIP tehnologije. Osim svih navedenih čimbenika bitnih za uspostavu suvremenog VoIP sustava u ovom radu je posebno opisana uspostava i mjerenje kvalitete audio usluge u IP mrežama. U tu svrhu je posebno obrađena tematika mjerenja audio usluge s naglaskom na objektivne metode mjerenja kvalitete govora. Za ilustraciju je dan primjer mjerenja karakterističnih za VoIP komponente sustava kontrole zračne plovidbe. Dodatno su u laboratoriju simulirana mjerenja na tri različita audio kodeka kako bi se pokazalo ponašanje određenih mrežnih parametara na kvalitetu prenošenog govora.

Abstract (english)

The speech transmission via IP networks represents a kind of challenge for today's communications. From the time of traditional PSTN systems the speech transmission has reached a completely new dimension through VoIP. Besides the telecommunication technologies there are other technologies as well as their characteristic aspects that are interlacing here. It is mainly corresponding to signalling methods, speech as an audio signal processing, security and economical aspects of using VoIP. Finally, special care is given to the quality of service delivery as a basic requirement on VoIP systems. Benefits of using VoIP technology are presented generally. Besides all of these factors important for establishing a modern VoIP system this thesis is primarily describing the establishment and the measurement of the audio service quality in IP networks. For that purpose, chapter with measurements of audio service with emphasis on objective measurement of the speech quality is particularly elaborated. As an illustration, there is an example of measurements characteristic for an air traffic management VoIP system presented here. Additionally, there are some measurement simulations made in the laboratory for three different audio codecs in order to show some results of the different network parameters affecting the speech quality transmission.

• Keywords: VoIP; signalizacija; sigurnost; kvaliteta govora; objektivna mjerenja; upravljanje zračnim prometom
• Keywords (english): VoIP; signaling; security; speech quality; objective measurements; air traffic management
• Language: croatian
• URN:NBN: urn:nbn:hr:168:558313
• Project: Number: 036-0361630-1633; Title: Predviđanje, motrenje i zaštita od buke; Leader: Hrvoje Domitrović; Jurisdiction: Croatia; Funder: MZOS; Funding stream: ZP
• Study programme: Title: Postgraduate master programme in electrical engineering; Study programme type: university; Study level: postgraduate; Academic / professional title: Magistar znanosti elektrotehnike (Magistar znanosti elektrotehnike)
• Catalog URL: http://lib.fer.hr/cgi-bin/koha/opac-detail.pl?biblionumber=37121
• Type of resource: Text
• Extent: 139 str ; 30 cm
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2020-08-26 09:02:15