Abstract: A method of operation in an ethernet receiver circuit is disclosed. The method comprises sampling an input signal to generate a sampled signal having a sampled noise component and a sampled data component. The sampled signal is sliced, and a slicer error determined based on the slicing of the sampled signal. A subsequently sampled noise component is filtered based on the slicer error.

Abstract: A communications system and method for switching data rates while maintaining convergence of adaptive components. The data rates can switch between, for example, 10G, 1G, 100M and the like. The adaptive components can include, for example, equalizers, cross-talk filters (e.g., NEXT filters; FEXT filters), transmission drivers, low density parity checks and echo cancellers. The data rate is reduced by maintaining the same symbol rate over a channel, while reducing the number of channels, reducing the symbol alphabet, and zero-filling unused bits in the transmission frame. In addition, full duplex communication can be changed to simplex communication. A usage rotation (e.g., a round robin rotation) switches among different twisted pairs of a communication channel to maintain convergence of the adaptive components. Inactive components can be powered down, or the power can be reduced, in order to reduce the amount of power required for the communications system.

Abstract: Embodiments of methods and apparatus for fast link recover are disclosed. One method includes sensing a link quality failure of a link between a receiver and a transmitter. If a link quality failure is sensed, then the receiver selects new pre-coder settings for the transmitter. The receiver communicates the new pre-coder settings to the transmitter. The transmitter applies the new pre-coder settings. The receiver computes its equalizer settings based on the new pre-coder settings of the transmitter. One apparatus or transceiver includes a means for determining a link quality failure of a link between the transceiver and a link partner transceiver. The transceiver selects new pre-coder settings for the link partner transceiver if a link quality failure is sensed. Additionally, the transceiver communicates the new pre-coder settings to the link partner transceiver, and computes its equalizer settings based on the new pre-coder settings of the link partner transceiver.

Abstract: An apparatuses and methods of setting power back-off of a master transceiver and a slave transceiver is disclosed. One example of a method includes the master transceiver determining a master power back-off, and the slave transceiver determining a slave power back-off based on signals received from the master transceiver, and based on the master power back-off. One example of an apparatus includes a master transceiver and slave transceiver system. The slave transceiver is connected to the master transceiver through a cable. The master transceiver includes means for determining a master power back-off. The slave transceiver includes means for determining a slave power back-off based on signals received from the master transceiver, and based on the master power back-off.

Abstract: Embodiments of methods, apparatuses and systems for transceiver processing are disclosed. One method includes a transceiver receiving a data stream from a link partner transceiver. A link parameter of a link between the transceiver and the link partner transceiver is determined. Allocation of transceiver processing between high-latency processing and low-latency processing is based at least in part on the link parameter.

Abstract: Embodiments of methods, apparatuses, and systems for preprocessing a transmit signal of a transceiver are disclosed. One method includes estimating parameters of a communication link between the transceiver and a link partner transceiver, estimating cross-talk coupling of the transceiver to at least one other transceiver, and adjusting at least one of a transmit power or a transmit signal waveform based on the estimated parameters and estimated cross-talk. One apparatus includes a transceiver that is operative to obtain parameters of a communication link between the transceiver and a link partner transceiver, and to obtain a representation of cross-talk coupling of the transceiver to at least one other transceiver. Further, a controller of the transceiver is operative to adjust at least one of a transmit power level or a transmit signal waveform based on the estimated parameters and estimated cross-talk.

Abstract: Embodiments of methods and apparatuses for reducing electromagnetic interference in a receive signal are disclosed. One method includes receiving a receive signal. An analog cancellation signal is generated. The analog cancellation signal is summed with a receive signal, thereby mitigating electromagnetic interference in the receive signal. One apparatus includes a transceiver that includes a receive analog to digital converter (ADC) sampling a receive signal. Electromagnetic interference (EMI) processing circuitry generates an analog cancellation signal. The analog cancellation signal is summed with a receive signal, thereby mitigating electromagnetic interference in the receive signal.

Abstract: A transceiver with a compensator circuit and a method for signaling are disclosed. A common mode signal detector in the transceiver detects a common mode signal, and the compensator circuit adjusts one or more component of a differential signal based on the common mode signal to pre-compensate the differential signal so that the effect of noise interference or imbalance in the circuitry is reduced.

Abstract: An ethernet transceiver integrated circuit chip is disclosed including a plurality of transceivers for coupling to a corresponding plurality of physical channels. A channel switcher is coupled to the plurality of transceivers. During a first mode of operation, the channel switcher activates all of the plurality of transceivers to transceive data in accordance with a first aggregate data transfer rate. During a second mode of operation, the channel switcher activates less than all of the plurality of transceivers to transceive data in accordance with a second aggregate data rate that is less than the first aggregate data transfer rate.

Abstract: A transceiver system is disclosed. The transceiver system comprises a first transceiver physical layer circuit (PHY) having a first plurality of channels and a second transceiver PHY disposed adjacent the first transceiver PHY and having a second plurality of channels. Filter circuitry is coupled between at least one of the plurality of first channels and at least one of the plurality of second channels.

Abstract: Rejecting radio frequency (RF) interference in a communication system. In one aspect, rejecting RF interference includes receiving a signal on a signal path of a receiver from a communication channel, the signal including one or more received signal components having a frequency within a predetermined subset range of frequencies within an operating signal bandwidth of the receiver. The received signal components are attenuated using a notch filter to reduce RF interference obtained during transmission of the signal over the communication channel. In some embodiments, the one or more signal components have been boosted in power at a link partner transmitter connected to the communication channel.

Abstract: A method of operation in a receive circuit is disclosed. The method comprises entering an initialization mode followed by receiving training data from a lossy signaling path. The training data originates from a transmit circuit. The received training data is sampled and minimax transmit equalizer coefficients are generated based on the sampled data. The minimax transmit equalizer coefficients are then transmitted back to the transmit circuit. The initialization mode is exited and an operating mode initiated, where transmit data precoded by the minimax transmit equalizer coefficients is received.

Abstract: An apparatuses and methods of setting power back-off of a master transceiver and a slave transceiver is disclosed. One example of a method includes the master transceiver determining a master power back-off, and the slave transceiver determining a slave power back-off based on signals received from the master transceiver, and based on the master power back-off. One example of an apparatus includes a master transceiver and slave transceiver system. The slave transceiver is connected to the master transceiver through a cable. The master transceiver includes means for determining a master power back-off. The slave transceiver includes means for determining a slave power back-off based on signals received from the master transceiver, and based on the master power back-off.

Abstract: A multi-PAM line driver circuit to drive input data along a transmission line from a voltage source is disclosed. The driver circuit includes a voltage source to supply a regulated voltage and a regulator current. A main branch is coupled between the voltage source and the transmission line and includes variable impedance circuitry. The main branch draws a drive current from the voltage source. A compensating branch is coupled to the voltage source in parallel with the main branch and includes a second variable impedance circuit to draw a compensating current from the voltage source based on the drive current, such that a sum of the drive current and the compensating current is substantially constant during the transmission of the input data.

Abstract: A transceiver circuit is disclosed. The transceiver circuit comprises a receive path to receive a differential signal and a first crosstalk filter coupled to the receive path. A common-mode path is provided for carrying a common-mode signal. An RFI interference filter is coupled between the common-mode path and the receive path. Isolation circuitry decouples the RFI interference filter from the first crosstalk filter.

Abstract: Embodiments of a method and apparatus for generating an estimated non-linear echo signal are disclosed. One method includes receiving a plurality of data inputs. The plurality of data inputs are partitioned into subsets. A weight vector is computed for each of the subsets. A vector of addresses to memory locations is computed for each of the subsets. Values of interpolants are accessed at the memory locations (interpolation sites) based on the vector of addresses for each of the subsets. The estimated non-linear echo signal based is calculated on the values of the interpolants and the weight vector corresponding to each subset.

Abstract: Fast retraining of communication parameters for a transceiver in a communication network. In one aspect, it is determined that the transceiver has lost the communication link for data communication, and the transceiver receives a signal providing a fast retraining sequence that updates transceiver parameters in order to reacquire the link for the data communication. The fast retraining sequence is performed in a reduced time relative to a full training sequence used for initializing the parameters for data communication by the transceiver.

Abstract: A magnetic package for a communication system is disclosed the package comprises a plurality of transformers, wherein each transformer comprises a differential transformer. Each differential transformer comprises at least 2 sets of three pins. Each transformer is coupled to a twisted pair channel and a transceiver. The magnetic package includes at least one common mode transformer coupled to at least one of the transformers, wherein the at least one common mode transformer includes at least three pins. The at least three pins for the at least one common mode transformer are in a position relative to the other pins such that the package size is minimized.

Abstract: In one implementation, a transceiver is provided that includes a precoder to pre-equalize a data signal transmitted from the transceiver. The transceiver further includes an interference cancellation system to substantially cancel interference from a data signal received by the transceiver. The precoder and the interference cancellation system share at least one common input signal.

Abstract: An iterative decoder configured to implement a min-sum with correction algorithm. The iterative decoder includes N parity check nodes coupled to M equality constraint nodes. The iterative decoder further includes a first parity check node configured to send an output to a first equality constraint node. Responsive to a minimum magnitude of other M?1 inputs to the first parity check node being lower than a pre-determined threshold, the parity check node sends the output having a same magnitude as that of the minimum magnitude of the other M?1 inputs to the first parity check node. Responsive to the minimum magnitude of the other M?1 inputs to the first parity check node being greater than the pre-determined threshold, the parity check node subtracts a correction factor in the form of p·2q from the minimum magnitude.