An example method for radio frequency (RF) signal fault signature isolation in cable network environments is provided and includes searching in phase domain for an echo in a channel response characterizing a channel in a cable network, the channel facilitating communication of a multi-tone signal in the cable network; identifying a phase in which the echo is found; calculating a tap amplitude corresponding to the identified phase, the calculated tap amplitude being indicative of group delay in the channel; correcting for the group delay in the multi-tone signal, for example, by subtracting the calculated tap amplitude from the multi-tone signal; and identifying a fault signature when amplitude of the corrected signal is greater than a threshold and the identified fault signature triggers operational maintenance of the cable network.

Systems and techniques relating to channel degradation detection for communication systems are described. A described system includes an interface to transmit signals and receive signals via a channel that includes a cable; an echo canceller coupled with the interface, the echo canceller to perform echo cancellation based on echo tap values to remove portions of the transmitted signals that appear as echoes within the received signals; an equalizer coupled with the interface, the equalizer to perform signal equalization based on equalizer tap values, the equalizer tap values being determined based on at least a portion of the received signals to adjust an impulse response of the channel and reduce inter-symbol interference within the received signals; and circuitry configured to determine a return loss channel quality indicator of the channel based on the echo tap values, determine an insertion loss channel quality indicator of the channel based on the equalizer tap values, or both.

Systems and techniques relating to channel degradation detection for communication systems are described. A described system includes an interface to transmit signals and receive signals via a channel that includes a cable; an echo canceller coupled with the interface, the echo canceller to perform echo cancellation based on echo tap values to remove portions of the transmitted signals that appear as echoes within the received signals; an equalizer coupled with the interface, the equalizer to perform signal equalization based on equalizer tap values, the equalizer tap values being determined based on at least a portion of the received signals to adjust an impulse response of the channel and reduce inter-symbol interference within the received signals; and circuitry configured to determine a return loss channel quality indicator of the channel based on the echo tap values, determine an insertion loss channel quality indicator of the channel based on the equalizer tap values, or both.

An example method for radio frequency (RF) signal fault signature isolation in cable network environments is provided and includes searching in phase domain for an echo in a channel response characterizing a channel in a cable network, the channel facilitating communication of a multi-tone signal in the cable network; identifying a phase in which the echo is found; calculating a tap amplitude corresponding to the identified phase, the calculated tap amplitude being indicative of group delay in the channel; correcting for the group delay in the multi-tone signal, for example, by subtracting the calculated tap amplitude from the multi-tone signal; and identifying a fault signature when amplitude of the corrected signal is greater than a threshold and the identified fault signature triggers operational maintenance of the cable network.

An example method for radio frequency (RF) signal fault signature isolation in cable network environments is provided and includes searching in phase domain for an echo in a channel response characterizing a channel in a cable network, the channel facilitating communication of a multi-tone signal in the cable network; identifying a phase in which the echo is found; calculating a tap amplitude corresponding to the identified phase, the calculated tap amplitude being indicative of group delay in the channel; correcting for the group delay in the multi-tone signal, for example, by subtracting the calculated tap amplitude from the multi-tone signal; and identifying a fault signature when amplitude of the corrected signal is greater than a threshold and the identified fault signature triggers operational maintenance of the cable network.

Systems and techniques relating to channel degradation detection for communication systems are described. A described system includes an interface to transmit signals and receive signals via a channel that includes a cable; an echo canceller coupled with the interface, the echo canceller to perform echo cancellation based on echo tap values to remove portions of the transmitted signals that appear as echoes within the received signals; an equalizer coupled with the interface, the equalizer to perform signal equalization based on equalizer tap values, the equalizer tap values being determined based on at least a portion of the received signals to adjust an impulse response of the channel and reduce inter-symbol interference within the received signals; and circuitry configured to determine a return loss channel quality indicator of the channel based on the echo tap values, determine an insertion loss channel quality indicator of the channel based on the equalizer tap values, or both.

Systems and techniques relating to channel degradation detection for communication systems are described. A described system includes an interface to transmit signals and receive signals via a channel that includes a cable; an echo canceller coupled with the interface, the echo canceller to perform echo cancellation based on echo tap values to remove portions of the transmitted signals that appear as echoes within the received signals; an equalizer coupled with the interface, the equalizer to perform signal equalization based on equalizer tap values, the equalizer tap values being determined based on at least a portion of the received signals to adjust an impulse response of the channel and reduce inter-symbol interference within the received signals; and circuitry configured to determine a return loss channel quality indicator of the channel based on the echo tap values, determine an insertion loss channel quality indicator of the channel based on the equalizer tap values, or both.

A communication device includes: a signal generator configured to generate a first signal and supply the first signal to a telephone line; a terminator having a variable terminal impedance as seen from the telephone line; a detector configured to detect a difference between the terminal impedance and a line impedance of the telephone line; and a controller configured to determine the terminal impedance so that the difference is reduced.

An Ethernet device includes a link test pulse (LTP) generator circuit, a hybrid circuit, a transmit (TX) circuit, a receive (RX) circuit, and a post-processing circuit. The LTP generator circuit generates an LTP signal that is compliant with an IEEE 802.3 standard. The TX circuit transmits the LTP signal to an Ethernet cable through the hybrid circuit. The RX circuit receives an RX signal from the hybrid circuit during a period in which the LTP signal is transmitted through the hybrid circuit. The post-processing circuit performs a cable diagnosis of the Ethernet cable according to the RX signal.

An Ethernet device includes a link test pulse (LTP) generator circuit, a hybrid circuit, a transmit (TX) circuit, a receive (RX) circuit, and a post-processing circuit. The LTP generator circuit generates an LTP signal that is compliant with an IEEE 802.3 standard. The TX circuit transmits the LTP signal to an Ethernet cable through the hybrid circuit. The RX circuit receives an RX signal from the hybrid circuit during a period in which the LTP signal is transmitted through the hybrid circuit. The post-processing circuit performs a cable diagnosis of the Ethernet cable according to the RX signal.