Abstract We studied the VoIP services with the integrated telephones with the emphasis on the features and ability. We have used an adapter Grandstream which is the analog telephone and the integration is studied. We have studied the performance of VoIP services by identifying the value of key quality parameters. We observed that the mean value of the jitter is oscillated around the allowed... We studied the VoIP services with the integrated telephones with the emphasis on the features and ability. We have used an adapter Grandstream which is the analog telephone and the integration is studied. We have studied the performance of VoIP services by identifying the value of key quality parameters. We observed that the mean value of the jitter is oscillated around the allowed value. It should be noted that the Jitter was successfully compensated by the receiving buffers and had no influence on the conversation speech. During the trials it is observed that the key QoS parameters defined for the conversation speech were reasonable. It is possible to confirm the successful integration of analog telephones into the VoIP service which is the crux of this work. Read More Read Less

Abstract Elearning involves the proper use of the models, method, tasks, the material base and the problems in the teaching process using the digital phase locked loop. We have studied the many types of phase and phase frequency detectors. Their parameters are assessed and the features of different applications are discussed. We in this work developed and tested Different types of... Elearning involves the proper use of the models, method, tasks, the material base and the problems in the teaching process using the digital phase locked loop. We have studied the many types of phase and phase frequency detectors. Their parameters are assessed and the features of different applications are discussed. We in this work developed and tested Different types of digital integrators and digital filters along with the different phase-frequency detectors. Besides we experimented the circuits for Digitally Controlled Oscillators. Also many varied phase locked loops are built and tested. Then finally we have described the parameters used. Read More Read Less

Abstract Using dumbbell type defected ground structure, we present simulation and analysis of edge coupled microstrip filter. With the help of the full wave electromagnetic simulator, we have studied the coupling coefficients of the resonators of defected ground structure. Besides, we published the design graphs of the coupling coefficient used for filter synthesis. We simulate the five pole filter that help... Using dumbbell type defected ground structure, we present simulation and analysis of edge coupled microstrip filter. With the help of the full wave electromagnetic simulator, we have studied the coupling coefficients of the resonators of defected ground structure. Besides, we published the design graphs of the coupling coefficient used for filter synthesis. We simulate the five pole filter that help for the production and measurements. We found that the correlation between simulation and obtained results are very strong. Read More Read Less