The Research And Application Practice Of The Evaluation Model Of Speech Quality Based On E-model

The development of VoIP results in the altitudinal attention. The quality of VoIP becomes a important part of VoIP. Because the quality of IP phone can not be guaranteed, so VoIP voice quality testing has become critical.Firstly, this paper gives a simple introduction about the foreground of VoIP and the significance of quality of VoIP. Then, this paper introduces two primary session control protocols and a media transport protocol. The session control protocols are SIP, H.323and the media transport protocol is RTP. Then, it analyzes the VoIP system and its work principle. And then this paper analyzes the factors that affect the quality of VoIP and their characteristics. Then this paper introduces the compact E-Model for the voice quality testing system in the point of view of code damnification and network damnification.Finally the design and realization of the IP phone quality test software based on E-Model is discussed. Design ideas, realization of the module function are treated in detail and the software testing results are analyzed which improved the correctness and usability. The transmission parameters R of the software gained from voice quality formula E-Model based on the ITU-TG.107. The voice quality score MOS is got by the conversion of R and MOS. Some parameters of the formula use the default values of ITU-TG107. While other parameters that can tested by the software such as delay, packet loss rate are got by testing the actual network.The IP phone quality test software can not only get a visual voice quality score MOS, but also reflect network characteristics such as delay and packet loss data. Operators and users can test whether the IP telephone is right by the software easily. And IP telephone can do some adjustments according to these specific performance parameters.Collected through the core of IP bearer network management system, network latency and packet loss of data, and ultimately the application of the algorithm, the mobile network in Chongqing MOS values are calculated in real time, and achieved good application effect.