Abstract: An apparatus is disclosed, which may include: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to perform: receiving downlink channel estimates between a plurality of access point (AP) antennas of one or more APs and a plurality of user equipment (UE) antennas of one or more UEs; iteratively updating a set of power allocation weights for the AP antennas using weights extracted from a precoder; computing the precoder based on the received channel estimates and a previous set of power allocation weights; performing the iterative updates until a stopping criterion is reached; and outputting data representative of a precoder computed from the received channel estimates and the updated set of power allocation weights.

Abstract: An apparatus is disclosed, which may include: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to perform: receiving downlink channel estimates between a plurality of access point (AP) antennas of one or more APs and a plurality of user equipment (UE) antennas of one or more UEs; iteratively updating a set of power allocation weights for the AP antennas using weights extracted from a precoder; computing the precoder based on the received channel estimates and a previous set of power allocation weights; performing the iterative updates until a stopping criterion is reached; and outputting data representative of a precoder computed from the received channel estimates and the updated set of power allocation weights.

Abstract: Echo cancellation for a two-way audio communication includes receiving, at an AEC system from microphone(s), an audio signal based on, at least in part, near-end signals and reproduced far-end signals. Loudspeaker(s) reproduced the far-end signals. The AEC system is operated, at least in part, with filter(s) so as to update estimates of coefficients of an acoustic channel from the loudspeaker(s) to the microphone(s). Control parameter(s) affecting an operation of the AEC system that is/are configurable and is/are set to value(s), from a range of values, is/are determined, based on estimating an accuracy of the estimates of the coefficients of the acoustic channel and a characteristic of the near-end signals. The AEC system controls the filter(s) with different values of the control parameter(s) at different times.

Abstract: An apparatus comprises: a first plurality of first radio frequency chains; a second plurality of second radio frequency chains, the first radio frequency chains being configured to produce wider side-band emissions than the second radio frequency chains; at least one antenna array comprising antenna elements, each of a first plurality of the antenna elements being coupled with a corresponding one of the first plurality of first radio frequency chains, the first plurality of first radio frequency chains being configured to cause transmissions predominately in a first band within a channel, each of a second plurality of the antenna elements being coupled with a corresponding one of the second plurality of second radio frequency chains, the second plurality of second radio frequency chains being configured to cause transmissions predominately in at least one second band within the channel.

Abstract: An AEC system can implement different updating techniques for echo cancellation. A Block Maximum Likelihood updating technique updates filter coefficients typically at integer multiples of a block size. A Proportional-Incremental Maximum Likelihood updating technique applies proportional weighting to the updates of filter coefficients. A Multi-source Incremental Maximum Likelihood updating technique uses separate control parameters associated with each of multiple loudspeakers. Combinations of these may be used, and one or more of these can be selected and implemented in real-time.

Abstract: Echo cancellation for a two-way audio communication includes receiving, at an AEC system from microphone(s), an audio signal based on, at least in part, near-end signals and reproduced far-end signals. Loudspeaker(s) reproduced the far-end signals. The AEC system is operated, at least in part, with filter(s) so as to update estimates of coefficients of an acoustic channel from the loudspeaker(s) to the microphone(s). Control parameter(s) affecting an operation of the AEC system that is/are configurable and is/are set to value(s), from a range of values, is/are determined, based on estimating an accuracy of the estimates of the coefficients of the acoustic channel and a characteristic of the near-end signals. The AEC system controls the filter(s) with different values of the control parameter(s) at different times.

Abstract: In accordance with an embodiment, the method includes determining a second sequence of numbers of digits for encoding the respective integer coefficient values of the first sequence, the second sequence including, as first element, a first number of digits for encoding the first integer coefficient value of the first sequence, and as second and subsequent elements, constrained numbers of digits that are greater than or equal to respective minimum required numbers of digits for encoding the second and subsequent integer coefficient values of the first sequence. The constrained numbers of digits are such that any two successive elements of the second sequence do not differ from each other by more than a given threshold value. The method further includes encoding difference values between the successive elements of the second sequence; and encoding the integer coefficient values of the first sequence using the respective numbers of digits of the second sequence.

Abstract: A vectoring controller for configuring a vectoring processor that jointly processes DMT communication signals to be transmitted over, or received from, a plurality of N subscriber lines according to a vectoring matrix. In accordance with an embodiment, the vectoring controller is configured, for given ones of a plurality of tones, to enable the given tone for direct data communication over a first set of N?Mk targeted lines out of the plurality of N subscriber lines, and to disable the given tone for direct data communication over a second disjoint set of Mk supporting lines out of the plurality of N subscriber lines, Mk denoting a non-null positive integer. The vectoring controller is further configured to configure the vectoring matrix to use an available transmit or receive power at the given tone over the second set of Mk supporting lines for further enhancement of data signal gains at the given tone over the first set of N?Mk targeted lines.

Abstract: In accordance with an embodiment, the method includes detecting an update event whereupon a precoder needs to be updated, sending signal adjustment information to a receiver remotely coupled to a subscriber line out of the plurality of subscriber lines indicative of a signal compensation factor to be applied to a receive communication signal to compensate for a channel bias caused by the scheduled precoder update, and time-coordinating the precoder update with the enforcement of the signal compensation factor at the receiver.

Abstract: In accordance with an embodiment, the method includes determining a second sequence of numbers of digits for encoding the respective integer coefficient values of the first sequence, the second sequence including, as first element, a first number of digits for encoding the first integer coefficient value of the first sequence, and as second and subsequent elements, constrained numbers of digits that are greater than or equal to respective minimum required numbers of digits for encoding the second and subsequent integer coefficient values of the first sequence. The constrained numbers of digits are such that any two successive elements of the second sequence do not differ from each other by more than a given threshold value. The method further includes encoding difference values between the successive elements of the second sequence; and encoding the integer coefficient values of the first sequence using the respective numbers of digits of the second sequence.

Abstract: An apparatus comprises: a first plurality of first radio frequency chains; a second plurality of second radio frequency chains, the first radio frequency chains being configured to produce wider side-band emissions than the second radio frequency chains; at least one antenna array comprising antenna elements, each of a first plurality of the antenna elements being coupled with a corresponding one of the first plurality of first radio frequency chains, the first plurality of first radio frequency chains being configured to cause transmissions predominately in a first band within a channel, each of a second plurality of the antenna elements being coupled with a corresponding one of the second plurality of second radio frequency chains, the second plurality of second radio frequency chains being configured to cause transmissions predominately in at least one second band within the channel.

Abstract: In accordance with an embodiment, the method includes detecting an update event whereupon a precoder needs to be updated, sending signal adjustment information to a receiver remotely coupled to a subscriber line out of the plurality of subscriber lines indicative of a signal compensation factor to be applied to a receive communication signal to compensate for a channel bias caused by the scheduled precoder update, and time-coordinating the precoder update with the enforcement of the signal compensation factor at the receiver.

Abstract: In accordance with an embodiment, the method includes determining a second sequence of numbers of digits for encoding the respective integer coefficient values of the first sequence, the second sequence including, as first element, a first number of digits for encoding the first integer coefficient value of the first sequence, and as second and subsequent elements, constrained numbers of digits that are greater than or equal to respective minimum required numbers of digits for encoding the second and subsequent integer coefficient values of the first sequence. The constrained numbers of digits are such that any two successive elements of the second sequence do not differ from each other by more than a given threshold value. The method further includes encoding difference values between the successive elements of the second sequence; and encoding the integer coefficient values of the first sequence using the respective numbers of digits of the second sequence.

Abstract: A vectoring controller is configured to determine first coefficient values for a vectoring matrix at a first tone based on a first number of iterations through an iterative update algorithm and a first channel matrix estimate at the first tone, and to determine second coefficient values for the vectoring matrix at a second neighboring tone based on a second number of iterations through the iterative update algorithm and a second channel matrix estimate at the second tone. The vectoring controller is configured to start with the first coefficient values as initial values for the respective second coefficient values in the iterative update algorithm. The second number of iterations is lower than or equal to the first number of iterations.

Abstract: A vectoring controller is configured to determine first coefficient values for a vectoring matrix at a first tone based on a first number of iterations through an iterative update algorithm and a first channel matrix estimate at the first tone, and to determine second coefficient values for the vectoring matrix at a second neighboring tone based on a second number of iterations through the iterative update algorithm and a second channel matrix estimate at the second tone. The vectoring controller is configured to start with the first coefficient values as initial values for the respective second coefficient values in the iterative update algorithm. The second number of iterations is lower than or equal to the first number of iterations.

Abstract: A multi-line digital transceiver configured to use digital signal vectoring in a manner that causes effects of crosstalk between distinct groups of subscriber lines to be effectively mitigated, without directly attempting to mitigate effects of crosstalk within any one of those distinct groups. In an example embodiment, effects of crosstalk within each of the distinct groups can be mitigated indirectly using an appropriate T/FDMA schedule, according to which, during a given symbol period, a given resource block of any of the distinct groups can carry data corresponding to a single respective subscriber. A precoder (postcoder) matrix for the digital signal vectoring can be generated using block-diagonalization techniques appropriately constrained, e.g., using the groups' definitions, aggregate-transmit-power restrictions, etc. In various embodiments, the disclosed digital signal vectoring can be used on the downlink or on the uplink, or both.

Abstract: A multi-line digital transceiver configured to use low-complexity beamforming on at least some tones to boost effective SNR values for selected subscriber lines. In an example embodiment, the beamforming coefficients can be restricted to one-bit values or two-bit values, e.g., such that the corresponding beamforming computations can be implemented using only sign changes, swaps of the real and imaginary parts, and/or zeroing of some values, and without invoking any full-precision hardware multiplication operations. At least some embodiments can be run on a significantly simpler and/or less powerful vectoring engine than conventional beamforming solutions while still being able to provide nearly optimal beamforming SNR gains. In some embodiments, additional scaling by powers of two may be applied to at least some signals contributing to the beamforming, e.g., to satisfy power constraints for some or all of the subscriber lines.

Abstract: A multiport FDX data transceiver having (i) digital transmit and receive chains shared by the multiple ports thereof and (ii) a multi-stage echo-cancellation circuit capable of canceling the echo of the transmitted signal that is coupled back into the receive chain through the analog front end of the transceiver. In an example embodiment, the echo-cancellation circuit comprises two stages. The first stage operates to remove a dominant echo signal corresponding to the output signal that is being broadcast on the multiple ports of the transceiver. The second stage operates to remove a residual echo signal typically caused by differences in the pertinent characteristics of the circuits associated with the different ports of the transceiver. In some embodiments, the multi-stage echo-cancellation circuit can be used for training a single-stage echo-cancellation circuit that may be unable to sufficiently quickly converge on an optimal set of filter coefficients on its own.

Abstract: A vectoring controller for configuring a vectoring processor that jointly processes DMT communication signals to be transmitted over, or received from, a plurality of N subscriber lines according to a vectoring matrix. In accordance with an embodiment, the vectoring controller is configured, for given ones of a plurality of tones, to enable the given tone for direct data communication over a first set of N?Mk targeted lines out of the plurality of N subscriber lines, and to disable the given tone for direct data communication over a second disjoint set of Mk supporting lines out of the plurality of N subscriber lines, Mk denoting a non-null positive integer. The vectoring controller is further configured to configure the vectoring matrix to use an available transmit or receive power at the given tone over the second set of Mk supporting lines for further enhancement of data signal gains at the given tone over the first set of N?Mk targeted lines.

Abstract: A multi-line digital transceiver configured to use low-complexity beamforming on at least some tones to boost effective SNR values for selected subscriber lines. In an example embodiment, the beamforming coefficients can be restricted to one-bit values or two-bit values, e.g., such that the corresponding beamforming computations can be implemented using only sign changes, swaps of the real and imaginary parts, and/or zeroing of some values, and without invoking any full-precision hardware multiplication operations. At least some embodiments can be run on a significantly simpler and/or less powerful vectoring engine than conventional beamforming solutions while still being able to provide nearly optimal beamforming SNR gains. In some embodiments, additional scaling by powers of two may be applied to at least some signals contributing to the beamforming, e.g., to satisfy power constraints for some or all of the subscriber lines.