System and method for testing digital subscriber lines

• US 6,584,148 B1
• Filed: 06/02/2000
• Issued: 06/24/2003
• Est. Priority Date: 06/02/2000
• Status: Expired due to Term

• Current Assignee: Quarterhill Inc. (f/k/a Wi-LAN Inc.)
• Original Assignee: Nokia, Inc. (Nokia Corporation)
• Inventors: Sands, Jeffrey J., Banks, Kevin R., Zitting, Brent R., Roberson, Ron M., Rigby, Mark O., Deaton, Robert D.
• Primary Examiner(s): TSE, YOUNG TOI
• Application Number:
  US09/586,330
• Time in Patent Office: 1,117 Days
• Field of Search: 375/219, 375/222, 375/224, 375/377, 379/27.01, 379/27.03, 379/27.04, 379/29.01, 379/29.11, 379/32.01, 379/32.04, 379/27.05, 379/27.06, 379/27.07
• US Class Current: 375/222
• CPC Class Codes: H04L 43/50 Testing arrangements
• CPC Class Codes: H04M 3/2209 for lines also used for data transmission
• CPC Class Codes: H04M 3/30 for subscriber's lines , for the local loop

Abstract

A system for testing a communication path for digital subscriber line (DSL) signals includes a loop management device coupled in the communication path between a DSL access multiplexer (DSLAM) and a DSL modem located at a customer premises. The system also includes a remote test interface coupled in the communication path between the loop management device and the DSL modem. The loop management device and the remote test interface communicate using voice-band signals transmitted over the communication path and collaboratively test the communication path.

Claims

1. A system for testing a communication path for digital subscriber line (DSL) signals, comprising:

a loop management device coupled in the communication path between a DSL access multiplexer (DSLAM) and a DSL modem located at a customer premises;

a remote test interface coupled in the communication path between the loop management device and the DSL modem, comprising a first interface coupled to a first portion of the communication path, the first portion of the communication oath coupled to the DSL modem, said first portion comprises a tip wire and a ring wire;

a second interface coupled to a second portion of the communication path, the second portion of the communication oath coupled to the loop management device, wherein the remote test interface is further operable to disconnect the first portion of the communication oath from the second Portion of the communication path to perform testing of the second portion in collaboration with the loop management device, said second portion comprises a tip wire and a ring wire;

wherein, the loop management device and the remote test interface are operable to communicate using voice-band signals transmitted over the communication path and the loop management device and the remote test interface are further operable to collaboratively test the communication path without the use of a trained technician by providing a locator tone in order to find the communication oath and the remote test interface is still further operable to disconnect the tip wire of the first portion from the tip wire of the second portion and disconnect the ring wire of the first portion from the ring wire of the second portion to form an open circuit for testing.

2. The system of claim 1, wherein the loop management device is further operable to transmit an open loop signal to the remote test interface, the open loop signal instructing the remote test interface to form the open circuit for a specified period of time.

3. The system of claim 1, wherein the loop management device is further operable to measure noise on the second portion of the communication path.

4. The system of claim 1, wherein the loop management device is further operable to measure a capacitance of the second portion of the communication path.

5. The system of claim 1, wherein:

the remote test interface is further operable to transmit test signals over the second portion of the communication path; and

the loop management device is further operable to receive the test signals and measure an insertion loss in the second portion of the communication path.

6. A system for testing a communication path for digital subscriber line (DSL) signals, comprising:

a loop management device coupled in the communication path between a DSL access multiplexer (DSLAM) and a DSL modem located at a customer premises;

a remote test interface coupled in the communication path between the loop management device and the DSL modem, comprising a first interface is coupled to a first portion of the communication path, the first portion of the communication oath coupled to the DSL modem, said first portion comprises a tip wire and a ring wire;

a second interface coupled to a second portion of the communication path, the second portion of the communication path coupled to the loop management device, wherein the remote test interface is further operable to disconnect the first portion of the communication path from the second portion of the communication path to perform testing of the second portion in collaboration with the loop management device, said second portion comprises a tip wire and a ring wire;

wherein the loon management device and the remote test interface operable to communicate using voice-band signals transmitted over the communication path and the loon management device and the remote test interface are further operable to collaboratively test the communication path without the use of a trained technician by providing a locator tone in order to find the communication path and the remote test interface is further operable to disconnect the tip wire of the first portion from the tip wire of the second portion and disconnect the ring wire of the first portion from the ring wire of the second portion; and

the remote test interface is still further operable to connect the tip wire and the ring wire of the second portion to form a short circuit for testing.

7. The system of claim 6, wherein the loop management device is further operable to transmit a short loop signal to the remote test interface, the short loop signal instructing the remote test interface to form the short circuit for a specified period of time.

8. The system of claim 6, wherein the loop management device is further operable to measure a resistance of the tip wire and the ring wire of the second portion of the communication path.

9. A method for testing a communication path for digital subscriber line (DSL) signals, comprising:

coupling a loot management device in the communication path between a DSL access multiplexer (DSLAM) and a DSL modem located at a customer premises;

coupling a remote test interface in the communication oath between the loop management device and the DSL modem;

transmitting voice-band signals between the loop management device and the remote test interface over the communication path to facilitate communication between the loop management device and the remote test interface;

testing the communication oath using the loop management device in collaboration with the remote test interface;

disconnecting a first portion and a second portion of the communication path using the remote test interface, comprising;

disconnecting a tip wire of the first portion from a tip wire of the second portion; and

disconnecting a ring wire of the first portion from a ring wire of the second portion to form an open circuit for testing, wherein the first portion of the communication oath is coupled to a first interface of the remote test interface and to the DSL modem, and wherein the second portion of the communication oath coupled to a second interface of the remote test interface and to the loop management device; and

transmitting an open loop signal from the loop management device to the remote test interface, the open loop signal instructing the remote test interface to form the open circuit for a specified period of time.

10. The method of claim 9, further comprising measuring noise on the second portion of the communication path using the loop management device.

11. The method of claim 9, further comprising measuring a capacitance of the second portion of the communication path using the loop management device.

12. The method of claim 9, further comprising:

transmitting test signals from the remote test interface over the second portion of the communication path;

receiving the test signals at the loop management device; and

measuring an insertion loss in the second portion of the communication path.

13. The method of claim 9, further comprising incorporating the remote test interface with the DSL modem.

14. The method of claim 9, further comprising coupling the remote test interface to the DSL modem using an auxiliary communication line to facilitate communication with the DSL modem when a DSL service is inoperative.

15. The method of claim 14, further comprising coupling the auxiliary communication line to an RS-232 serial port of the DSL modem.

16. The method of claim 14, further comprising:

transmitting voice-band signals from the loop management device to the remote test interface over the communication path;

receiving the voice-band signals at the remote test interface;

converting the voice-band signals to a format appropriate for transmission over the auxiliary communication line; and

communicating the voice-band signals to the DSL modem using the auxiliary communication line.

17. The method of claim 9, further comprising:

transmitting a locator tone from the loop management device over the communication path during an installation of the remote test interface;

detecting the locator tone at the remote test interface; and

transmitting an acknowledge signal from the remote test interface to the loop management device over the communication path.

18. A method for testing a communication path for digital subscriber line (DSL) signals, comprising:

coupling a loop management device in the communication path between a DSL access multiplexer (DSLAM) and a DSL modem located at a customer premises;

coupling a remote test interface in the communication path between the loop management device and the DSL modem;

transmitting voice-band signals between the loop management device and the remote test interface over the communication path to facilitate communication between the loop management device and the remote test interface;

testing the communication path using the loop management device in collaboration with the remote test interface;

disconnecting a first portion and a second portion of the communication path using the remote test interface, comprising;

disconnecting a tip wire of the first portion from a tip wire of the second portion and disconnecting a ring wire of the first portion from a ring wire of the second portion;

connecting the tip wire and the ring wire of the second portion to form a short circuit for testing; and

transmitting a short loop signal from the loop management device to the remote test interface, the short loop signal instructing the remote test interface to form the short circuit for a specified period of time.

19. The method of claim 18, further comprising measuring a resistance of the tip wire and the ring wire of the second portion of the communication path using the loop management device.