In voice packet communication, a fluctuation is produced in the delay time in the network. This makes the packet, which is originally continuous, discontinuous at the receiver, and results in an interruption. The interruption deteriorates the voice quality. Then it is necessary that a delay should be provided at the side of the receiver to absorb the interruption. If the delay for absorbing the fluctuation is too small, the delay cannot sufficiently be absorbed; and if it is too large, the total delay is increased. In either case, the quality of the voice or speech is deteriorated. From such a viewpoint, this paper discusses the absorption of the delay fluctuation of the voice packet. To set the delay for absorbing the fluctuation, the quality of the voice containing interruptions must be evaluated. First, an objective evaluation measure is presented which is well aligned to the subjective evaluation of the deterioration of the voice quality with interruption. A control method to ensure the voice quality above a certain level is presented, which examines the objective evaluation measure for the varying traffic in the network. The method adjusts adaptively the delay for absorbing the delay fluctuation so that the voice quality is kept above a certain reference value.
|Number of pages
|Electronics and Communications in Japan (Part I: Communications)
|Published - 1991 Apr
ASJC Scopus subject areas
- Computer Networks and Communications
- Electrical and Electronic Engineering