Prospajanje digitalnog govornog signala u transmisijskoj mreži bez uporabe transkodera

scientific master's theses

• Author: Ante Burilović
• Mentor: Branko Mikac (mentor)
• Committee member: Vjekoslav Sinković (predsjednik povjerenstva)
• Committee member: Branko Mikac (član povjerenstva)
• Committee member: Vlasta Hudek (član povjerenstva)
• Committee member: Marijan Kunštić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Electrical Engineering and Computing; (Department of Telecommunications); Zagreb
• Defense date and country: 2003, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Electrical Engineering; Telecommunications and Informatics
• Universal decimal classification (UDC): 621.3 - Electrical engineering

Abstract

Predmet istraivanja ovog magistarskog rada je utjecaj uvođenja funkcije Prospajanja digitalnog govornog signala u transmisijskoj mrei bez uporabe transkodera na 2G i 3G mrene elemente i protokole. Funkcija je u literaturi i standardima poznata po kratici TrFO (Transcoder Free Operation). Transkodiranje govora degradira njegovu kvalitetu, te bi ga telekomunikacijski sustavi trebali izbjeći ako je moguće, pogotovo u sitacijama gdje pokretni uređaj i mrea podravaju zajednički tip kodeka. U radnji je dan pregled svih kodnih tipova koji se koriste u 2G i 3G mreama, s posebnim osvrtom na AMR (Adaptive Multi-Rate) kodni tip. Također su opisani mreni protokoli: BICC (Bearer-Independent Call Control) te H.248/Megaco, koji su neophodni za prijenos informacija vezanih za kontrolu traskodera izvan govornog kanala (OoBTC - Out of Band Transcoder Control). Radnja je posebno fokusirana na analizu utjecaja uvođenja TrFO funkcije u MSC (Mobile Switching Center) i MGW (Media Gateway) čvorovima, te su opisane nune izmjene u BICC protokolu. Također su opisani utjecaji na funkcioniranje postojećih korisničkih usluga.

Abstract (english)

The problem the thesis addresses is the analysis of the impacts on 2G and 3G network elements and protocols due to introduction of transcoder-free cross-connecting of digital voice signal in transmission network. In literature and standardizations documents, this feature is known as TrFO Transcoder Free Operation. The transcoding of speech may degrade quality and, therefore, mobile systems should try to avoid this if possible, when both user equipment and the network can support a common codec type. The thesis gives an overview of all codec types used in 2G and 3G networks, with attention to AMR (Adaptive Multi Rate). Network protocols: BICC (Bearer-Independent Call Control) and H.248/Megaco, required for transfer of OoBTC (Out of Band Transcoder Control) information, are described as well. In particular, the thesis is focused on the impacts on MSC (Mobile Switching Center) and MGW (Media Gateway) nodes. Necessary changes in BICC protocol are described, as well as impacts on existing services and functions.

• Keywords: Prospajanje bez uporabe transkodera; Kontrola transkodera izvan govornog kanala; Protokol za kontrolu poziva neovisan o prenosnoj tehnologiji; Adaptivni kodni tipovi s više modova prijenos; Komprimirani govor
• Keywords (english): Trancoder free operation; Out of band transcoder control; Bearer-independent call control; Adaptive multi-rate; Compressed speech
• Language: croatian
• URN:NBN: urn:nbn:hr:168:589461
• 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: https://lib.fer.hr:8443/cgi-bin/koha/catalogue/detail.pl?biblionumber=29175
• Type of resource: Text
• Extent: 117 str. ; 30 cm
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2019-09-11 12:48:32