Lidé

Ing. Ivan Pravda, Ph.D.

Všechny publikace

Prostředí pro otevřené digitální výukové zdroje VOVCR.CZ

  • Pracoviště: Katedra telekomunikační techniky
  • Anotace:
    Příspěvek popisuje inovativní prostředí pro digitální otevřené výukové zdroje. Zaměřuje se na jeho podstatné funkce a popisuje i vybrané typy objektů, které mohou být ve vzdělávacích zdrojích použity. Příspěvek dále přibližuje práci s portálem z pohledu autora vzdělávacího zdroje (tj. zpravidla učitele).

Assesment of VoIP Systems through E-model Extension

  • Autoři: Ing. Ivan Pravda, Ph.D.,
  • Publikace: RTT 2010 Proceedings. Ostrava: VŠB - TUO, FEI, Katedra elektroniky a telekomunikační techniky, 2010. pp. 196-199. ISBN 978-80-248-2261-7.
  • Rok: 2010
  • Pracoviště: Katedra telekomunikační techniky
  • Anotace:
    The first part of this paper is focused to the methodology for objective quantification of the quality of transmission through the impairment factors closely associated with the utilization of wideband speech codecs in telecommunication networks. The second part describes realized speech tests in connection with Signal-to-Noise Ratio (SNR).

Application of E-model for VoIP Systems Assessment

  • Autoři: Ing. Ivan Pravda, Ph.D.,
  • Publikace: 11th International Conference RTT 2009. Praha: České vysoké učení technické v Praze, 2009. pp. 0111_0024. ISBN 978-80-01-04410-0.
  • Rok: 2009
  • Pracoviště: Katedra telekomunikační techniky
  • Anotace:
    The primary objective of this paper is to deepen the methodology for objective quantification of the quality of transmission through the impairment factors closely associated with the utilization of wideband speech codecs in telecommunication networks. This methodology is based on subjective auditory listening-only tests, but the resulting impairment factors may be used for predicting speech quality in an instrumental way, e.g., for network planning purposes. Auditory test results are firstly transformed to an overall quality rating scale and then adjusted to rule out test-specific effect. The derived impairment factors fit into the common framework which is defined in recommendations by the E-model for narrowband telephone networks, and which is hereby extended towards wideband speech transmission.

Extended E-model for VoIP Systems Assessment

  • Autoři: Ing. Ivan Pravda, Ph.D., prof. Ing. Zdeněk Bečvář, Ph.D.,
  • Publikace: Proceedings of the 2009 Networking and Electronic Commerce Research Conference (NAEC 2009). Dallas, TX: American Telecommunications Systems Management Association Inc., 2009. pp. 85-91. ISBN 978-0-9820958-2-9.
  • Rok: 2009
  • Pracoviště: Katedra telekomunikační techniky
  • Anotace:
    The primary objective of this paper is to deepen the methodology for objective quantification of the quality of transmission through the impairment factors closely associated with the utilization of wideband speech codecs in telecommunication networks. This methodology is based on subjective auditory listening-only tests, but the resulting impairment factors may be used for predicting speech quality in an instrumental way, e.g., for network planning purposes. The derived impairment factors fit into the common framework which is defined in recommendations by the E-model for narrowband telephone networks, and which is hereby extended towards wideband speech transmission.

Modifikace E-modelu pro hodnocení přenosu VoIP

  • Pracoviště: Katedra telekomunikační techniky
  • Anotace:
    Cílem článku je zhodnotit možnosti použití současné metodiky posuzování kvality úzkopásmových kanálů (dF = 3,1 kHz) pro přenos řeči i pro kanály širokopásmové (dF = 7 kHz), navrhnout možná rozšíření existujících modelů a posoudit přínos širokopásmových kodeků na subjektivní kvalitu hovoru. Hlavní pozornost je pak věnována vlivu ztrátovosti paketů při IP přenosu na celkovou kvalitu hovorové komunikace.

Implementation of OTDR Method for Education Process

  • Autoři: Ing. Ivan Pravda, Ph.D.,
  • Publikace: RTT 2008. Bratislava: STU v Bratislave, 2008. ISBN 978-80-227-2939-0.
  • Rok: 2008
  • Pracoviště: Katedra telekomunikační techniky
  • Anotace:
    The main objective of this paper is to present suggestions and ideas on how to use now generally known OTDR method for analysis of optical routes in education.

Possibilities of Telephone Bandwidth's Extension

  • Pracoviště: Katedra telekomunikační techniky
  • Anotace:
    The paper discusses possibilities of telephone bandwidth extension that could be used for prospective communication technologies.

Quality Evaluation of Narrowband and Wideband IP Telephony

  • Pracoviště: Katedra telekomunikační techniky
  • Anotace:
    Contemporary Next Generation Networks (NGN) are mainly built on Internet Protocol (IP). Major challenge for emerging types of wired and wireless IP-based networks is to provide adequate Quality of Service (QoS) for different services. Quality evaluation requires a detailed knowledge of the performance requirements for particular services and applications. The starting point for deriving these performance requirements must be the user.

A New Laboratory Network based on SDH technology

  • Autoři: Ing. Ivan Pravda, Ph.D.,
  • Publikace: RTT 2007. Žilina: University of Žilina, 2007. pp. 338-340. ISBN 978-80-8070-735-4.
  • Rok: 2007
  • Pracoviště: Katedra telekomunikační techniky
  • Anotace:
    A new laboratory network based on SDH technology is presented that has been built at the Department of Telecommunication Engineering.

Quality Planning for NGN Elements

Voice Quality Planning for NGN Including Mobile Networks

Estimating End-to-End Delay Based on Assemblies of Transmission Elements

  • Autoři: Ing. Ivan Pravda, Ph.D.,
  • Publikace: RTT 2005 Proceedings. Ostrava: VŠB - TUO, FEI, Katedra elektroniky a telekomunikační techniky, 2005. ISBN 80-248-0897-8.
  • Rok: 2005
  • Pracoviště: Katedra telekomunikační techniky
  • Anotace:
    Necessary parameters are analysed in detail and results used for optimization of next generation networks are retrieved.

Sítě UMTS

The Convergence of Voice and Data Services in Telecommunication Networks

  • Autoři: Ing. Ivan Pravda, Ph.D., Baloun, J.
  • Publikace: RTT 2004. Praha: ČVUT FEL, Katedra telekomunikační techniky, 2004. pp. 0249_0132. ISBN 80-01-03063-6.
  • Rok: 2004
  • Pracoviště: Katedra telekomunikační techniky
  • Anotace:
    Necessary condition for realisation of multiservice networks is reserving for useful quality of service, which is given by the specified marginal rate of delay, variation delay, information loss and others. These parameters are necessary in detail analysed and retrieved results use for optimization next generation networks.

New Laboratory of the Communication Technology

Technical Aspects of xDSL Systems

  • Autoři: Ing. Ivan Pravda, Ph.D.,
  • Publikace: COFAX - Telekomunikácie 2003. Bratislava: D&D STUDIO, 2003. pp. 259-260. ISBN 80-967019-4-0.
  • Rok: 2003

Technical Aspects of xDSL Systems

  • Autoři: Ing. Ivan Pravda, Ph.D.,
  • Publikace: RTT 2003 - Proceedings. Bratislava: FEI, Slovak University of Technology, 2003. pp. 210-212. ISBN 80-227-1934-X.
  • Rok: 2003

Za stránku zodpovídá: Ing. Mgr. Radovan Suk