Arrangement for measuring and controlling temporal relationships between channels of a multimedia communication system

摘要

A method for ascertaining the temporal relationship between two signals that traverse a network via two different channels concurrently sends a test signal through the two channels and evaluates the temporal relationship of the signal received at the outputs of the channels. The test signal is divided into presentation units and the temporal relationships are evaluated for foursomes of presentation units. A foursome of presentation units consists of an output presentation unit of one channel (channel 1), a matching input presentation unit of the same channel (channel 1), an input presentation unit of the other channel (channel 2) which has a time stamp that is identical, or essentially identical, to the time stamp of the input presentation unit of the one channel, and an output presentation unit of channel 2 which matches the input presentation unit of channel 2. The time stamps of the presentation units in the foursome are used to develop a measure of the difference in delays between the first channel and the second channel, as a set of difference thus obtained for different foursomes provides the data for a statistical evaluation of the difference in delays between the channels. This information is useful for various purposes, including adjusting the delay in the channels to obtain a more balanced transmission.