Jitter buffer loss estimate for effective equipment impairment factor

Abstract

The paper deals with a proposal of original E-model modification, the new model includes improvements giving more precise results when a jitter is present in transmission channel. Our idea is based on the fact that the network jitter can affect overall delay in delivery or a packet loss due to a limitation of play-out buffer in IP phones or VoIP gateways. Delay is incorporated in an impairment factor Id of E-model whereas losses are issue of Ie-eff parameter. We examined how the estimated speech quality is affected by jitter and compared computed results with MOS values gained by PESQ objective intrusive method (Perceptual Evaluation of Speech Quality). Experiments were performed in circumstances of varying delay, packet loss, jitter and play-out buffer. We have proved that the proposed modification improves estimated MOS computed by Emodel.