In accordance with embodiments disclosed herein, there are provided apparatus, systems and methods for implementing DSL line fault determination and localization via SELT, DELT, and MELT diagnostics. For example, such a system or computer implemented method may include means for: receiving Metallic Loop/Line Testing (MELT) test output from applying a MELT test to a DSL line; receiving Dual-End Line Testing (DELT) test output from applying a DELT test to the DSL line; receiving Single-Ended Loop Testing (SELT) test output from applying a SELT test to the DSL line; determining one or more faults are present on the DSL line by comparing the MELT test output, the DELT test output, and the SELT test output; and localizing the one or more determined faults by comparing the MELT test output, the DELT test output, and the SELT test output. Other related embodiments are disclosed.

A method, system, computer program product, and a device for testing are provided. In some implementations, a method includes the steps of (i) conducting a line test on a line of a line card that is not connected to a subscriber line; (ii) comparing the result of the test with a predetermined result; and (iii) determining a defect of the test hardware if the result deviates from the predetermined result. Furthermore, a device and a communication system comprising said device are suggested.

This invention relates to a method of managing a digital subscriber line, where an optimum point at which to trigger a line test on the DSL line is determined. The invention continuously measures the signal to noise (SNR) margin on the DSL line, and compares the measurements to predetermined conditions based on SNR margin characteristics associated with a population of good lines. Once the SNR margin measurements fail to meet the predetermined conditions, an electrical line test is triggered. Thus, monitoring is done in the DSL domain, but the line test triggered is in the electrical domain. In an improved method, moisture level sensors provide a measure of the atmospheric moisture levels experienced by the line. If the SNR margin measurements fail to meet the predetermined conditions, and in addition there is a correlation with atmospheric moisture levels, then a line test is triggered on the line. This improvement picks up faults associated with wet joints that are generally intermittent in nature, and otherwise difficult to identify and properly test.

In accordance with embodiments disclosed herein, there are provided apparatus, systems, and methods for identifying cable-level faults in a copper plant of a DSL system. For example, such means may include identifying a group of Digital Subscriber Lines (DSL lines) within a common cable; determining a baseline of physical line characteristics for each of the DSL lines in the group; collecting current physical line characteristics for each of the DSL lines in the group; determining a physical line characteristics delta for each of the DSL lines in the group by comparing the current physical line characteristics to the baseline of physical line characteristics for each of the respective DSL lines; and indicating a defect in the common cable based on a quantity of the DSL lines in the group for which the respective DSL line's physical line characteristics delta exceeds a threshold. Other related embodiments are disclosed.

A system, method, and apparatus to allow an operator of a broadcast communication system, such as a cable television or satellite television service to provide some examples, to diagnose performance of this communication system remotely. The operator of a first communication device, such as a cable modem termination system (CMTS) to provide an example, may remotely diagnosis performance problems, or potential performance problems, occurring at a second communication device, such as a cable modem (CM) to provide an example, or a group of second communication devices. For example, the operator of the first communication device may view a spectrum analysis of communication signals being routed to, processed by, and/or provided by the second communication device, or group of second communication devices, to diagnose the performance problems, or the potential performance problems, in real time.

The present disclosure relates to a Time Duplex Division (TDD) modem and a method in such a modem for making Single Ended Line Test (SELT) measurements. The device comprises a transmitter and a receiver and it has a normal mode of TDD communication. In these devices, Time Domain Reflectometry (TDR) is used as line measurement. It has a number of drawbacks, and for overcoming said drawbacks, Frequency Domain Reflectometry (FDR) measurement techniques adapted for TDD devices are suggested.

The present invention provides a method and a device for line initialization. In the method, first, a first precoding matrix needed by a first part of subcarriers is acquired in a downstream direction, and then multiple data signals of all data signals that need to be sent in an initialization process are sent by using only the first part of subcarriers; afterward, a second precoding matrix needed by at least a second part of subcarriers of all available subcarriers is acquired, and remaining data signals of all the data signals exclusive of the multiple data signals are sent by using the at least second part of subcarriers to complete line initialization. By using the foregoing manner, the present invention can cancel crosstalk between lines while completing line initialization, and does not easily cause transmit power to exceed a limit.

A method, system, computer program product, and a device for testing are provided. In some implementations, a method includes the steps of (i) conducting a line test on a line of a line card that is not connected to a subscriber line; (ii) comparing the result of the test with a predetermined result; and (iii) determining a defect of the test hardware if the result deviates from the predetermined result. Furthermore, a device and a communication system comprising said device are suggested.

Embodiments of the present invention relate to a method and an apparatus for sending a single-ended loop testing SELT measurement signal, and a control device. The method for sending a SELT measurement signal includes: aligning a synchronization symbol of a digital subscriber line on which a SELT diagnosis needs to be performed with a synchronization symbol of at least one DSL line for data transmission, where the synchronization symbol of the digital subscriber line on which a SELT diagnosis needs to be performed and the synchronization symbol of the at least one digital subscriber line for data transmission are uplink or downlink synchronization symbols; and carrying a SELT measurement signal over the aligned synchronization symbol of the DSL line on which a SELT diagnosis needs to be performed, where the SELT measurement signal is used to detect transmission quality or a line fault of the DSL line.

A method and Dynamic Line Management, DLM, system for controlling Digital Line Subscriber, DSL, connections, comprising applying a first line profile to a DSL connection, the first line profile specifying a first virtual noise template for the DSL connection, wherein the first virtual noise template specifies a first set of frequency dependent virtual noise levels for the DSL connection; configuring a connection parameter (such as the data rate) of the DSL connection based on the first set of frequency dependent virtual noise levels; applying a second line profile to the DSL transceiver unit, the second line profile specifying a second virtual noise template for the DSL connection, wherein the second virtual noise template specifies a second set of frequency dependent virtual noise levels for the DSL connection; and reconfiguring the connection parameter for the DSL connection based on the second set of frequency dependent virtual noise levels.