The present disclosure provides a communication device and a skew correction method thereof. The communication device includes a first signal transceiving device and a correction device. The correction device is coupled to the first signal transceiving device through multiple first channels in a correction mode, each of the first channels has multiple first sub-channels. In the correction mode, the first signal transceiving device simultaneously transmits multiple first data through all the first sub-channels of first channels, and the correction device receives the first data through all the first sub-channels to calculate first skew differences of all the first sub-channels, thus calculating first skew differences according to the first skew values.

Methods and systems are described for sequentially obtaining a plurality of data streams, the plurality of data streams comprising a data stream in a current condition, a data stream in a skewed-forward condition, and a data stream in a skewed-backward condition, calculating, for each data stream in the plurality of data streams, a corresponding set of cost-function values by obtaining a corresponding set of eye measurements, the eye measurements obtained by adjusting a sampling threshold of a sampler generating a plurality of samples of the data stream, the plurality of samples comprising edge samples and data samples, wherein the data stream is sampled at a rate equal to twice a rate of the data stream and calculating the corresponding set of cost-function values based on the corresponding set of eye measurements, and generating a skew control signal based on a comparison of the sets of calculated cost-function values.

Methods and systems are described for sequentially obtaining a plurality of data streams, the plurality of data streams comprising a data stream in a current condition, a data stream in a skewed-forward condition, and a data stream in a skewed-backward condition, calculating, for each data stream in the plurality of data streams, a corresponding set of cost-function values by obtaining a corresponding set of eye measurements, the eye measurements obtained by adjusting a sampling threshold of a sampler generating a plurality of samples of the data stream, the plurality of samples comprising edge samples and data samples, wherein the data stream is sampled at a rate equal to twice a rate of the data stream and calculating the corresponding set of cost-function values based on the corresponding set of eye measurements, and generating a skew control signal based on a comparison of the sets of calculated cost-function values.

A system for detecting a failure along a transmission line of a cable plant is provided. The system includes a mobile vehicle configured to travel along a pathway substantially proximate to the cable plant along a span of the transmission line, and a transmitter disposed with the mobile vehicle. The transmitter is configured to emit (i) a test signal capable of ingressing the transmission line at a location of the failure, and (ii) an information signal containing location and velocity data of the mobile vehicle. The test signal is configured to provide phase shift and Doppler frequency information to a receiver operably connected to the transmission line at a location upstream from the location of the failure.

A system for detecting a failure along a transmission line of a cable plant is provided. The system includes a mobile vehicle configured to travel along a pathway substantially proximate to the cable plant along a span of the transmission line, and a transmitter disposed with the mobile vehicle. The transmitter is configured to emit (i) a test signal capable of ingressing the transmission line at a location of the failure, and (ii) an information signal containing location and velocity data of the mobile vehicle. The test signal is configured to provide phase shift and Doppler frequency information to a receiver operably connected to the transmission line at a location upstream from the location of the failure.

Apparatuses (and methods of manufacturing same), systems, and methods concerning polyphase digital filters are described. In one aspect, an apparatus is provided, including at least one pair of subfilters, each having symmetric coefficients, and a lattice comprising two adders and feedlines corresponding to each of the at least one pair of subfilters, each having symmetric coefficients. In one aspect, the apparatus is a polyphase finite impulse response (FIR) digital filter, including an interpolator and a decimator, where each of the interpolator and the decimator have at least one pair of subfilters, each having symmetric coefficients, and a lattice comprising two adders and feedlines corresponding to each of the at least one pair of subfilters, each having symmetric coefficients.

Apparatuses (and methods of manufacturing same), systems, and methods concerning polyphase digital filters are described. In one aspect, an apparatus is provided, including at least one pair of subfilters, each having symmetric coefficients, and a lattice comprising two adders and feedlines corresponding to each of the at least one pair of subfilters, each having symmetric coefficients. In one aspect, the apparatus is a polyphase finite impulse response (FIR) digital filter, including an interpolator and a decimator, where each of the interpolator and the decimator have at least one pair of subfilters, each having symmetric coefficients, and a lattice comprising two adders and feedlines corresponding to each of the at least one pair of subfilters, each having symmetric coefficients.

This application provides a power line communication method. Wherein, a first node determines a channel status of a channel between a second node and the first node in an alternating current cycle. Then, the first node may divide the alternating current cycle into time windows based on the channel status, and determine modulation coding parameters used for data transmission between the second node and the first node in the time window obtained through division. Further, the first node may send information about the time window obtained through division and the modulation coding parameters used in the time window obtained through division to the second node.

This application provides a power line communication method. Wherein, a first node determines a channel status of a channel between a second node and the first node in an alternating current cycle. Then, the first node may divide the alternating current cycle into time windows based on the channel status, and determine modulation coding parameters used for data transmission between the second node and the first node in the time window obtained through division. Further, the first node may send information about the time window obtained through division and the modulation coding parameters used in the time window obtained through division to the second node.

Methods and systems are described for sequentially obtaining a plurality of data streams, the plurality of data streams comprising a data stream in a current condition, a data stream in a skewed-forward condition, and a data stream in a skewed-backward condition, calculating, for each data stream in the plurality of data streams, a corresponding set of cost-function values by obtaining a corresponding set of eye measurements, the eye measurements obtained by adjusting a sampling threshold of a sampler generating a plurality of samples of the data stream, the plurality of samples comprising edge samples and data samples, wherein the data stream is sampled at a rate equal to twice a rate of the data stream and calculating the corresponding set of cost-function values based on the corresponding set of eye measurements, and generating a skew control signal based on a comparison of the sets of calculated cost-function values.