Avaliação do índice de qualidade de voz em redes móveis celulares baseada na percepção dos usuários

Abstract

The mobile industry is, once again, in an intense transformation process with the definitive popularization of the voice and data services and the deployment of third generation networks in Brazil. The trend of significant growth in the sector is the result of the privatization model of the former telecommunications operators, the investment in new technologies, and especially, the great competition among companies. In this context, the purpose of this study is to perform a system analysis of the services quality indices provided by cellular mobile operators, specifically regarding to voice services. The main focus of the research will be to examine and propose the voice quality index in a new approach, where quality service is evaluated in terms of user´s perception. The assessing voice quality indice was based on the average of subjective evaluations, made by users through MOS score, and by objective evaluations using the PESQ algorithm. The evaluation process is done automatically by the end user’s decision to assign a subjective score to its last call made. Tests were carried out in real networks, at three operators that provide mobile telephone service in Manaus city. Four points, with different traffic characteristics, were chosen for data collection. The research results show that using the proposed methodology may be valuable to the sector regulator, as a metric for assessing the quality of voice service available for the users, as well as the operators themselves in the optimization and the development of their mobile networks