Abstract:
A network unit includes a non-linear precoder for jointly pre-processing transmit samples to be transmitted over respective communication channels for crosstalk mitigation. The non-linear precoder includes a first non-linear precoding stage configured to operate according to a first triangular precoding matrix and including a modulo function, followed by a second linear precoding stage configured to operate according to a second precoding matrix. The network unit further includes a first pilot signal generator configured to generate first pilot signals for pre-processing by the second precoding stage only to yield partially-precoded pilot signals for further transmission over the respective communication channels, and a controller configured to update the second precoding matrix based on first error measurements performed during the transmission of the partially-precoded pilot signals over the respective communication channels while keeping the first precoding matrix unaltered.
Abstract:
An apparatus includes a DSL transceiver configured to transit to a DSL wait state in which a power transmitted from the DSL transceiver to a local-end line is substantially reduced in response to an interruption or substantial stop at the DSL transceiver of reception of DSL communications from the local-end line. The DSL transceiver is configured to transmit to the local-end line a DSL acknowledge signal in response to receiving from the local-end line a DSL wait signal. The DSL transceiver is configured to resume to transmit DSL communications to the local-end line at a power substantially higher than the power transmitted thereto in the DSL wait state in response either to receiving from the local-end line DSL transmissions at a substantially higher power than received there from in the DSL wait state or to receiving from the local-end line a second DSL acknowledge signal.
Abstract:
The present invention relates to a vectoring controller (130) for configuring a vectoring processor (120) that jointly processes DMT communication signals (u
Abstract:
In one embodiment, the method includes determining (S410), at an access node (100), a precoder matrix for precoding transmission from the access node to a plurality of downstream devices (200) over a plurality of lines. The plurality of lines include high power lines and low power lines. The high power lines are in active communication and transmit more symbols per frame than the low power lines. The method further includes precoding (S420) a signal vector using the precoder matrix regardless of the symbols the signal vector is sending over the low power lines. Here, the determining determines the precoder matrix such that the precoding does not mitigate the cross-talk effect the high power lines have on the low power lines. The method also includes transmitting (S430) over the plurality of lines based on the precoded signal vector.
Abstract:
A method includes maintaining temporally parallel DSL data communication sessions with DSL modems of a group via a set of lines. In response to a substantial stop to reception of DSL communications from one of the DSL modems via one of the lines, the method includes transmitting a substantially reduced average power to the one of the lines and monitoring the one of the lines to determine whether reception of DSL communications has restarted from the one of the DSL modems. The method also includes resuming the maintaining of the temporally parallel DSL communication sessions in response to the monitoring determining that the reception of DSL communications from the one of the DSL modems has restarted.
Abstract:
A method involves performing a plurality of acts. The acts include transmitting a first signal stream to a first channel of a multi-channel communications medium while transmitting a second signal stream to a different second channel of the medium. The second signal stream is substantially temporally correlated to the first signal stream. The method includes receiving an SINR measured at a receiver configured to receive signals from the first channel. The SINR is measured while the receiver received the first signal stream. The method includes determining a channel matrix element between the first and second channels or a ratio of said channel matrix element to a diagonal element of the channel matrix. The act of determining is based on the received SINR.
Abstract:
A method includes maintaining temporally parallel DSL data communication sessions with DSL modems of a group via a set of lines. In response to a substantial stop to reception of DSL communications from one of the DSL modems via one of the lines, the method includes transmitting a substantially reduced average power to the one of the lines and monitoring the one of the lines to determine whether reception of DSL communications has restarted from the one of the DSL modems. The method also includes resuming the maintaining of the temporally parallel DSL communication sessions in response to the monitoring determining that the reception of DSL communications from the one of the DSL modems has restarted.
Abstract:
The present invention relates to a device (108, 109, 110) comprising an interface to at least one active subscriber line (112) and an interface to at least one inactive subscriber line (111). The device (108, 109, 110) comprises means for transmitting a first signal on the inactive subscriber line (111) and means for synchronously measuring crosstalk (130; 201, 203, 205, 207) induced into the active subscriber line (112) by transmitting the first signal on the inactive subscriber line (111).