This paper describes simulations of a test sequence transmission for intrusive measurement of VTQ... more This paper describes simulations of a test sequence transmission for intrusive measurement of VTQoS in mobile environment. The aim of the simulation was to analyze an influence of multipath signals propagation and propagation attenuation on the test sequence. Evaluation the generated sequences was based on the calculation of mean square measure and correlation coefficient. These measures were used as a criterion for suitable test sequences selection. Reconsideration of an influence of mobile environment on the test sequences, which are composed from simple signals, is the aim of this paper.
In this work, we experimentally study how behaviour of the PESQ-estimate varies with reference si... more In this work, we experimentally study how behaviour of the PESQ-estimate varies with reference signal characteristics. In particular we investigate the impact of different lengths of reference signal and active speech ratios on speech quality estimation in simulated VoIP environment. These two reference signal characteristics are defined very broadly by ITU-T Recommendation P.862.3. That is reason to investigate an impact of those characteristics on speech quality estimation more in depth. We assess the variability of PESQ estimations with respect to the reference signal characteristics and network conditions and finally offer some proposals for the purpose of more accurate and reliable speech quality assessment from those reference signal characteristics point of view in IP networks.
This document describes the simulations in transmission chain. The aim of simulations was to obta... more This document describes the simulations in transmission chain. The aim of simulations was to obtain optimal testing signal determined for automatic intrusive measurement VTQoS (Voice Transmission Quality of Service). Evaluation of simulation signal was based on calculation of mean square measure and correlation coefficient. Suitable signals of beforehand defined group were chosen on the basis of these parameters. Suitable signals will be used to create resulting test sequence.
This paper describes simulations of speech sequences transmission for intrusive measurement of vo... more This paper describes simulations of speech sequences transmission for intrusive measurement of voice transmission quality of service (VTQoS) in the environment of IP networks. The aim of the simulations was to investigate the impact of the different durations of speech sequences on speech quality from the jitter rate and packet loss point of view in IP networks. The ITU-T G.729 and ITU-T G.723.1 encoding schemes were used for the purpose of the simulations. The assessment of speech quality was realized by means of perceptual evaluation of speech quality (PESQ) algorithm. A comparison of the impact of different durations of speech sequences on speech quality and determination of the optimal duration of speech sequence for measurements of speech quality in telecommunication networks, is the aim of this paper.
This paper describes measurements of an impact of background traffic on speech quality in an envi... more This paper describes measurements of an impact of background traffic on speech quality in an environment of IP networks. The simulated background traffic consists of three types of current traffics in telecommunication networks such as data transfer service, multimedia streaming service and Web service. The background traffic was generated by means of the accomplished D -ITG traffic generator. The impact of these types of traffic and traffic load on speech quality using the test sequence and speech sequences is the aim of this paper. The assessment of speech quality is carried out by means of the accomplished PESQ algorithm. The proposal of a new method of improved detection of the critical conditions in telecommunication networks from the speech quality point of view is presented in this paper. Conclusion implies the next application of the method of improved detection of the critical conditions for the purpose of algorithms for link adaptation from the speech quality point of view in an environment of IP networks. The primary goal of these algorithms is improving speech quality in the VoIP connections, which are established in the competent link.
This paper describes measurements of the impact of background traffic on speech quality in an env... more This paper describes measurements of the impact of background traffic on speech quality in an environment of WLANs (IEEE 802.11). The simulated background traffic consists of three types of current traffics in telecommunication networks such as data transfer service, multimedia streaming service, and Web service. The background traffic was generated by means of the accomplished Distributed Internet Traffic Generator (D-ITG). The impact of these types of traffic and traffic load on speech quality using the test sequence and speech sequences is the aim of this paper. The assessment of speech quality is carried out by means of the accomplished Perceptual Evaluation of Speech Quality (PESQ) algorithm. The proposal of a new method for improved detection of the critical conditions in wireless telecommunication networks from the speech quality point of view is presented in this paper. Conclusion implies the next application of the method of improved detection of critical conditions for the purpose of algorithms for link adaptation from the speech quality point of view in an environment of WLANs. The primary goal of these algorithms is improving speech quality in the VoWLAN connections, which are established in the competent link.
This paper describes measurements of the impact of background traffic on speech quality in an env... more This paper describes measurements of the impact of background traffic on speech quality in an environment of WLANs (IEEE 802.11). The simulated background traffic consists of three types of current traffics in telecommunication networks such as data transfer service, multimedia streaming service, and Web service. The background traffic was generated by means of the accomplished Distributed Internet Traffic Generator (D-ITG). The impact of these types of traffic and traffic load on speech quality using the test sequence and speech sequences is the aim of this paper. The assessment of speech quality is carried out by means of the accomplished Perceptual Evaluation of Speech Quality (PESQ) algorithm. The proposal of a new method for improved detection of the critical conditions in wireless telecommunication networks from the speech quality point of view is presented in this paper. Conclusion implies the next application of the method of improved detection of critical conditions for the purpose of algorithms for link adaptation from the speech quality point of view in an environment of WLANs. The primary goal of these algorithms is improving speech quality in the VoWLAN connections, which are established in the competent link.
This paper describes simulations of test and speech sequences transmission for intrusive measurem... more This paper describes simulations of test and speech sequences transmission for intrusive measurement of Voice Transmission Quality of Service (VTQoS) in the environment of IP networks. The aim of simulations was detect environment influences on the quality of transmission sequences, particularly an influence of coding schemes, packets loss and the jitter on the transmission sequences. The evaluation of test and speech sequences simulations were based on the calculation of the mean square measure. Reconsideration of a convenience of the given test sequence, which is composed from simple signals, on intrusive measurement of VTQoS in the environment of IP networks is the aim of this paper.
This paper describes simulations of a test sequence transmission for intrusive measurement of VTQ... more This paper describes simulations of a test sequence transmission for intrusive measurement of VTQoS in mobile environment. The aim of the simulation was to analyze an influence of multipath signals propagation and propagation attenuation on the test sequence. Evaluation the generated sequences was based on the calculation of mean square measure and correlation coefficient. These measures were used as a criterion for suitable test sequences selection. Reconsideration of an influence of mobile environment on the test sequences, which are composed from simple signals, is the aim of this paper.
In this work, we experimentally study how behaviour of the PESQ-estimate varies with reference si... more In this work, we experimentally study how behaviour of the PESQ-estimate varies with reference signal characteristics. In particular we investigate the impact of different lengths of reference signal and active speech ratios on speech quality estimation in simulated VoIP environment. These two reference signal characteristics are defined very broadly by ITU-T Recommendation P.862.3. That is reason to investigate an impact of those characteristics on speech quality estimation more in depth. We assess the variability of PESQ estimations with respect to the reference signal characteristics and network conditions and finally offer some proposals for the purpose of more accurate and reliable speech quality assessment from those reference signal characteristics point of view in IP networks.
This document describes the simulations in transmission chain. The aim of simulations was to obta... more This document describes the simulations in transmission chain. The aim of simulations was to obtain optimal testing signal determined for automatic intrusive measurement VTQoS (Voice Transmission Quality of Service). Evaluation of simulation signal was based on calculation of mean square measure and correlation coefficient. Suitable signals of beforehand defined group were chosen on the basis of these parameters. Suitable signals will be used to create resulting test sequence.
This paper describes simulations of speech sequences transmission for intrusive measurement of vo... more This paper describes simulations of speech sequences transmission for intrusive measurement of voice transmission quality of service (VTQoS) in the environment of IP networks. The aim of the simulations was to investigate the impact of the different durations of speech sequences on speech quality from the jitter rate and packet loss point of view in IP networks. The ITU-T G.729 and ITU-T G.723.1 encoding schemes were used for the purpose of the simulations. The assessment of speech quality was realized by means of perceptual evaluation of speech quality (PESQ) algorithm. A comparison of the impact of different durations of speech sequences on speech quality and determination of the optimal duration of speech sequence for measurements of speech quality in telecommunication networks, is the aim of this paper.
This paper describes measurements of an impact of background traffic on speech quality in an envi... more This paper describes measurements of an impact of background traffic on speech quality in an environment of IP networks. The simulated background traffic consists of three types of current traffics in telecommunication networks such as data transfer service, multimedia streaming service and Web service. The background traffic was generated by means of the accomplished D -ITG traffic generator. The impact of these types of traffic and traffic load on speech quality using the test sequence and speech sequences is the aim of this paper. The assessment of speech quality is carried out by means of the accomplished PESQ algorithm. The proposal of a new method of improved detection of the critical conditions in telecommunication networks from the speech quality point of view is presented in this paper. Conclusion implies the next application of the method of improved detection of the critical conditions for the purpose of algorithms for link adaptation from the speech quality point of view in an environment of IP networks. The primary goal of these algorithms is improving speech quality in the VoIP connections, which are established in the competent link.
This paper describes measurements of the impact of background traffic on speech quality in an env... more This paper describes measurements of the impact of background traffic on speech quality in an environment of WLANs (IEEE 802.11). The simulated background traffic consists of three types of current traffics in telecommunication networks such as data transfer service, multimedia streaming service, and Web service. The background traffic was generated by means of the accomplished Distributed Internet Traffic Generator (D-ITG). The impact of these types of traffic and traffic load on speech quality using the test sequence and speech sequences is the aim of this paper. The assessment of speech quality is carried out by means of the accomplished Perceptual Evaluation of Speech Quality (PESQ) algorithm. The proposal of a new method for improved detection of the critical conditions in wireless telecommunication networks from the speech quality point of view is presented in this paper. Conclusion implies the next application of the method of improved detection of critical conditions for the purpose of algorithms for link adaptation from the speech quality point of view in an environment of WLANs. The primary goal of these algorithms is improving speech quality in the VoWLAN connections, which are established in the competent link.
This paper describes measurements of the impact of background traffic on speech quality in an env... more This paper describes measurements of the impact of background traffic on speech quality in an environment of WLANs (IEEE 802.11). The simulated background traffic consists of three types of current traffics in telecommunication networks such as data transfer service, multimedia streaming service, and Web service. The background traffic was generated by means of the accomplished Distributed Internet Traffic Generator (D-ITG). The impact of these types of traffic and traffic load on speech quality using the test sequence and speech sequences is the aim of this paper. The assessment of speech quality is carried out by means of the accomplished Perceptual Evaluation of Speech Quality (PESQ) algorithm. The proposal of a new method for improved detection of the critical conditions in wireless telecommunication networks from the speech quality point of view is presented in this paper. Conclusion implies the next application of the method of improved detection of critical conditions for the purpose of algorithms for link adaptation from the speech quality point of view in an environment of WLANs. The primary goal of these algorithms is improving speech quality in the VoWLAN connections, which are established in the competent link.
This paper describes simulations of test and speech sequences transmission for intrusive measurem... more This paper describes simulations of test and speech sequences transmission for intrusive measurement of Voice Transmission Quality of Service (VTQoS) in the environment of IP networks. The aim of simulations was detect environment influences on the quality of transmission sequences, particularly an influence of coding schemes, packets loss and the jitter on the transmission sequences. The evaluation of test and speech sequences simulations were based on the calculation of the mean square measure. Reconsideration of a convenience of the given test sequence, which is composed from simple signals, on intrusive measurement of VTQoS in the environment of IP networks is the aim of this paper.
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