Broadcom Corporation

Avago Technologies International Sales Pte. Limited

Avago Technologies General IP (singapore) Pte. Ltd.

Giuseppe Cusmai

Ramon Alejandro Gomez

Leonard Dauphinee

Young J Shin

Francesco Gatta

Takayuki Hayashi

Steven T Jaffe

Loke Kun Tan

Lin He

Hanli Zou

Massimo Brandolini

Chun-Ying Chen

Avi Kliger

Xi Chen

Randall Bret Perlow

Anatoli Shindler

Jianhong Xiao

Hong Liu

Peter Cangiane

Bryan Juo-Jung Hung

Vijayaramalingam Periasamy

Flavio Avanzo

Eliran Hania

In some aspects, the disclosure is directed to methods and systems for improving signal to noise ratios of signals from multiple communication links. In some embodiments, a system includes a first frequency transformation circuit configured to transform a first signal in a time domain received from a first device into a corresponding second signal in a frequency domain. The system further includes a second frequency transformation circuit configured to transform a third signal in the time domain received from a second device into a corresponding fourth signal in the frequency domain. The system further includes a leg combining circuit configured to select, for a group of subcarriers, one of the first frequency transformation circuit and the second frequency transformation circuit, and cause, for the group of subcarriers, the selected frequency transformation circuit to output one of the second signal and the fourth signal, according to the selection.

Leg combining by FFT selection

Systems and methods relate to providing a transmit signal. The transmit signal can be provided in a transmitter circuit including a main pre-equalizer, a main power amplifier in communication with the main pre-equalizer, a replica pre-equalizer, and a replica power amplifier in communication with the replica pre-equalizer. The replica preamplifier is in communication with the main pre-equalizer, and control signals are provided to the main pre-equalizer to reduce distortion. The control signals are provided in response to an output signal of the replica power amplifier.

System for and method of reducing transmit signal distortion

A method and apparatus is disclosed to couple a transmission amplifier and a reception amplifier to a shared medium. An output of the transmission amplifier is directly coupled to an input of the reception amplifier to form a common connection. The transmission amplifier and the reception amplifier may receive a first amplifier bias via the common connection. In response to the first amplifier bias, the transmission amplifier provides a first communication signal to the shared medium and the reception amplifier does not provide a second communication signal from the shared medium. Alternatively, the transmission amplifier and the reception may receive a second amplifier bias via the common connection. In response to the second amplifier bias, the reception amplifier provides the second communication signal from the shared medium and the transmission amplifier does not provide the first communication signal to the shared medium.

Direct coupled radio frequency (RF) transceiver front end

A system includes a weighting element, a transconductance circuit, a feedback loop, and an auxiliary loop. In some implementations, the transconductance circuit may accept an input and provide a first portion of an output for amplification at a variable amplification level to generate an amplifier output. The feedback loop may provide a portion of the amplifier output as a first feedback to the input. The first feedback may be associated with an impedance that may vary with the amplification level. The auxiliary loop may provide a second feedback to the input to reduce the dependence of the impedance on the amplification level.

Gain invariant impedance feedback amplifier

Various multi-lane ADCs are disclosed that substantially compensate for impairments present within various signals that result from various impairments, such as phase offset, amplitude offset, and/or DC offset to provide some examples, such that their respective digital output samples accurately represent their respective analog inputs. Generally, the various multi-lane ADCs determine various statistical relationships, such as various correlations to provide an example, between these various signals and various known calibration signals to quantify the phase offset, amplitude offset, and/or DC offset that may be present within the various signals. The various multi-lane ADCs adjust the various signals to substantially compensate for the phase offset, amplitude offset, and/or DC offset based upon these various statistical relationships such that their respective digital output samples accurately represent their respective analog inputs.

Compensation for lane imbalance in a multi-lane analog-to-digital converter (ADC)

Systems and methods for demodulating a plurality of contiguous channels contained within a bandlimited portion of a radio-frequency (RF) input signal are provided. In an embodiment, the bandlimited portion of the RF input signal is down-converted to baseband. After down-conversion, the bandlimited portion overlaps at baseband with a mirror image of the bandlimited portion. The plurality of contiguous channels within the down-converted signal similarly overlap at baseband and subsequently occupy a bandwidth substantially equal to half that required before down-converting. Image rejection is performed in the digital domain to recover each of the plurality of overlapping channels.

Variable low IF receiver for multi-channel applications

A system comprises a first amplifier stage including a first amplifier, a second amplifier stage including second and third amplifiers, and a fourth amplifier. The first amplifier stage includes an input and an output. The second amplifier stage is coupled between the output of the first amplifier stage and a first output node. The fourth amplifier is coupled between the input of the first amplifier stage and a second output node.

Amplifier for cable and terrestrial applications with independent stage frequency tilt

Multi-tuner variable low IF receiver for multi-channel applications

A system and method for over-voltage protection of a power amplifier is provided. A power amplifier is typically employed in a transmitter to amplify signals prior to transmission via a load; the load may include an antenna or a cable. As a result of an impedance mismatch between the power amplifier and its load, excess power from the power amplifier output fails to reach the load and must be dissipated by one or more transistors in the power amplifier. In severe impedance mismatch conditions, this dissipated power may damage or destroy the transistor(s). An automatic gain control (AGC) is provided for detecting a gain difference between the power amplifier and a replica power amplifier. A gain difference may signal an over-voltage situation. The AGC may be configured to adjust the gain of the power amplifier if a gain difference exists to prevent device damage.

System and method for over-voltage protection of a power amplifier

Growing community of inventors

Irvine, CA, United States of America

Giuseppe Cusmai