Marvell International Limited

Trellisware Technologies, Inc.

Xiaopeng Chen

Runsheng He

William Lo

Jianqing Lin

Shuran Wei

Hubertus Notohamiprodjo

Keith Michael Chugg

In some implementations, an apparatus includes an echo canceller that generates an echo interference compensation signal that compensates for an echo interference signal in a communication signal, a crosstalk canceller that generates a crosstalk interference compensation signal that compensates for a crosstalk interference signal in the communication signal, and a combiner that generates a combined interference compensation signal based on the echo interference compensation signal and the crosstalk interference compensation signal.

Interference signal compensation

A system including a processor that receives a first digital signal corresponding to a first signal received by the system, and a second digital signal corresponding to a second signal transmitted by the system; generates a first control signal based on the first and second digital signals; and generates a first output signal based on the first control signal and a second analog signal corresponding to the second signal. A cancellation device generates a second control signal based on a first analog signal corresponding to the first signal, and a third control signal based on the first control signal and the first output signal; selects the second or third control signal when the system operates in a first or a second mode; and outputs a second output signal to cancel interference in the first signal according to the second analog signal and one of the second and third control signals.

Adaptive analog echo/next cancellation

A compensator generating a compensation signal to compensate for nonlinear echo in an output of a current source. The nonlinear echo is a result of transitioning the current source between an ON state and an OFF state. The compensator includes driving, weighting, function, and compensating circuits. The driving circuit receives a first signal that is based on the output of the current source. The weighting circuit is configured to generate a second signal based on weighted versions of the first signal. The function circuit, based on the second signal, (i) updates each of multiple functions, and (ii) selects a first function. The driving circuit generates a driving signal based on the first function selected by the function circuit. The compensating circuit generates the compensation signal based on the driving signal to compensate for the nonlinear echo provided by the output of the current source.

Method and apparatus to compensate for nonlinear echo in an output of a current source

Method and apparatus for reducing echo and crosstalk in a communication system

A nonlinear echo compensator comprises a mapping circuit that includes a weighting circuit that generates a weighted signal based on a current symbol and a prior symbol and a function generating circuit that selects one of N functions based on the weighted signal, where N is an integer greater than one. The mapping circuit generates a driving signal based on the selected one of the N functions and the weighted signal. A canceling circuit generates a nonlinear echo compensation signal based on the driving signal.

Nonlinear echo compensator for class B transmitter line driver

An adaptive analog echo/near-end crosstalk (NEXT) cancellation system includes a processor configured to receive a first digital signal corresponding to a first signal received by the system, receive a second digital signal corresponding to a second signal transmitted by the system, and generate a first error control signal based on each of the first digital signal and the second digital signal. A cancellation device is configured to generate a second error control signal based on a first analog signal corresponding to the first signal. The cancellation device selectively outputs the second error control signal or the first error control signal based on whether the system is operating in a first mode or a second mode, respectively. The cancellation device selectively outputs a cancellation signal according to one of the second error control signal and the first error control signal, and a second analog signal corresponding to the second signal.

Methods and apparatus describe techniques for reducing interference signals in a communication signal. An apparatus includes, in at least one aspect, a transceiver circuit to receive a communication signal that includes one or more interference signals and a compensation circuit to generate a compensation signal to compensate for the one or more interference signals in the communication signal based on one or more cancellation coefficients and one or more data symbols.

Method and apparatus for reducing an interference signal in a communication system

A transceiver includes an analog front end (AFE) device and first, second, third, and fourth transmitters. A digital signal processor (DSP) receives digital receive signal and digital transmit signals and generates a shared error control signal and first, second, third, and fourth individual error control signals. An echo canceller system generates an estimated echo signal. First, second, and third NEXT canceller systems generate first, second, and third estimated NEXT signals, respectively, each based on the second analog receive signal and respective ones of the analog transmit signals from the second, third, and fourth transmitters during the first mode and each based on the shared error control signal, respective ones of the second, third, and fourth individual error control signals, and the respective ones of the analog transmit signals from the second, third, and fourth transmitters during the second mode.

Adaptive analog echo/NEXT cancellation

Circuits, systems, methods and software for controlling a power conversion and/or correcting and/or controlling a power factor in such conversion(s). The present invention generally takes a computational approach to reducing or minimizing zero current periods in the critical mode of power converter operation, and advantageously reduces zero current periods in the critical mode of power converter operation, thereby maximizing the power factor of the power converter in the critical mode and reducing noise that may be injected back into AC power lines. The present power factor controller allows for greater design flexibility, reduced design complexity, and reduced resolution and greater tolerance for error in certain parameter measurements useful in power factor correction and/or control.

Circuits, systems, methods, and software for power factor correction and/or control

A physical layer device includes a converter module to convert input data having a first predetermined number of bits into output data having a second predetermined number of bits. A scrambler module is operable to be activated and deactivated. The scrambler module receives the output data having the second predetermined number of bits. An encoding module modulates the output of the scrambler module in accordance with one of a plurality of modulation types and generates an encoded output signal having an output level. The encoding module is operable to vary the output levels of the encoded output signal.

Multispeed communications device

An adaptive analog echo/near-end crosstalk (NEXT) cancellation system includes a selector that outputs a first error control signal when a first receive signal does not include a remotely transmitted signal and a second error control signal when the first receive signal includes a remotely transmitted signal. An echo/NEXT cancellation module communicates with the selector and generates an estimated echo/NEXT signal based on the first error control signal and a first transmit signal when the first receive signal does not include a remotely transmitted signal and based on the second error control signal and the first transmit signal when the first receive signal includes a remotely transmitted signal. A summing module receives the first receive signal and the estimated echo/NEXT signal and generates an echo/NEXT filtered receive signal by subtracting the estimated echo/NEXT signal from the first receive signal.

A physical layer device comprises a mode selector that selects a mode. A clock selects a clock frequency from T clock frequencies based on the mode. A converter module selects one of N mapping functions based on the mode and converts an n-bit input to an m-bit output based on the selected one of the N mapping functions. A scrambler module scrambles the m-bit output or passes the m-bit output unchanged based on the mode. An encoding module modulates the m-bit output based on the selected clock frequency and one of M modulation modes selected based on the mode, where T, n, m, N and M are integers greater than one and n is not equal to m.

Methods and apparatus describe techniques for reducing interference signals in a communication signal. A communication signal is received through a receiver. The communication signal contains an interference signal. A digital replica of the interference signal is generated, the digital replica is converted into a corresponding analog replica of the interference signal. The analog replica of the interference signal is subtracted from the communication signal.

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Sunnyvale, CA, United States of America

Xiaopeng Chen