Science – Future of Lithuania / Mokslas – Lietuvos Ateitis, Vol 5, No 2 (2013)

Voice Quality in Mobile Telecommunication System

Evaldas Stankevičius

Abstract


The article deals with methods measuring the quality of voice transmitted over the mobile network as well as related problem, algorithms and options. It presents the created voice quality measurement system and discusses its adequacy as well as efficiency. Besides, the author presents the results of system application under the optimal hardware configuration. Under almost ideal conditions, the system evaluates the voice quality with MOS 3.85 average estimate; while the standardized TEMS Investigation 9.0 has 4.05 average MOS estimate. Next, the article presents the discussion of voice quality predictor implementation and investigates the predictor using nonlinear and linear prediction methods of voice quality dependence on the mobile network settings. Nonlinear prediction using artificial neural network resulted in the correlation coefficient of 0.62. While the linear prediction method using the least mean squares resulted in the correlation coefficient of 0.57. The analytical expression of voice quality features from the three network parameters: BER, C / I, RSSI is given as well.

Article in Lithuanian


Article in: Lithuanian

Article published: 2013-05-24

Keyword(s): QoS; PESQ; 3SQM; MOS; linear and non-linear prediction; artificial neural networks; LMS

DOI: 10.3846/mla.2013.28

Full Text: PDF pdf

Science – Future of Lithuania / Mokslas – Lietuvos Ateitis ISSN 2029-2341, eISSN 2029-2252
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 License.