Automated channel test unit
AssigneeAT&T Bell Laboratories
InventorsLane J. Abrams, Kevin Loughran, David W. Masukewicz, Robert L. Overstreet, Jr.
Life of this patent
Estimating the term…
Abstract
Disclosed is a circuit for the automatic testing of channel units such as found in subscriber loop carrier (SLC.RTM.) systems. The circuit is included as part of the remote terminal of the system and performs type tests, power-up tests and routine verification tests. The circuit also monitors the subscriber channel, and connects the subscriber in the event of a ringing signal or an off-hook during a test. The results of the test are sent to a display unit which can be located at the remote terminal and/or the central office.
Claims20
A digital loop transmission system apparatus comprising:
- a central office terminal;
- a remote terminal having a plurality of channel units, the remote terminal further including a test unit comprising:
- means for applying to the channel units appropriate terminations and detectors for testing the channel units;
- means for controlling the application of the terminations and detectors;
- and
- means for providing access to digital transmission signals.
An apparatus located at a remote terminal for testing channel units comprising:
- means for applying to the channel units appropriate terminations and detectors for testing the channel units;
- means for controlling the application of the terminations and detectors;
- and
- means for providing access to digital transmission signals to and from the channel units.
A method for testing at a remote terminal a channel unit which is coupled to a central office terminal in a digital loop transmission system comprising the steps of:
- coupling the channel unit to a test unit at the remote terminal;
- applying appropriate terminations and detectors from the test unit to the channel unit;
- and
- periodically coupling the channel unit through the test unit to a digital path, and monitoring the digital signals between the channel unit and central office terminal to determine the presence of a ringing signal or an off-hook signal.
A method for determining the type of channel unit present in a remote terminal which is coupled to a central office terminal in a digital loop transmission system comprising the steps of:
- coupling the channel unit to a test unit at the remote terminal;
- applying appropriate terminations and detectors from the test unit to the channel unit;
- applying appropriate digital signals from the test unit to a digital path coupled to the channel unit;
- and
- detecting the resulting signal from the channel unit.
Dependencies are inferred from the claim text.