Digital signal processor-based telephone test set analysing and displaying multiple signal parameter data for terminal mode and line monitor mode operation

摘要

A digital signal processor-based test set is programmed to enable a craftsperson to monitor, receive and process signals of a variety of formats that may be present on a line under test, including user feature analog modem signals. Such feature signals may include caller-identification signals, visual message waiting indicator signals, and analog display services interface signals. The test set employs a signal processing routine that operates in two modes: 1- terminal mode - in which the test set functions in the place of customer premises equipment (CPE); and 2- line monitor mode - in which the test set is connected to the line under test and monitors data signals being transmitted to and received from an existing CPE. In both modes the test set has the ability to not only display the data being sent but also parametric information. IMAGE