Advanced Micro Devices Corporation

Sunnyvale Micro Devices, Inc.

Colin D Nayler

Atul Garg

Yi Cheng

Boon-Aik Ang

Philip J Keller

Oikwan Tsang

Kyongsoo Michael Jung

Hung Duy Vo

Dennis Lau

Paul K Jung

Phil Keller

Zhen-Hua Liu

A physical layer transceiver, configured for retrieving signal samples from a prescribed network medium having an undetermined length, includes a digital feedforward equalizer, configured for generating equalized signal samples from the retrieved signal samples and based on supplied equalizer settings, and an equalizer controller. The equalizer controller is configured for supplying selected equalizer settings that overcome intersymbol interference encountered by transmission of the signal samples across the prescribed network medium. The equalizer controller is configured for supplying prescribed initial equalizer settings to the digital feedforward equalizer, receiving equalized signal samples from the digital feedforward equalizer, and selectively changing the prescribed initial equalizer settings based on comparing the equalized signal samples to a prescribed equalization threshold. The equalizer controller is configured for selectively repeating the changing of the equalizer settings until the equalized signal samples reach the prescribed equalization threshold.

Arrangement for initializing digital equalizer settings based on comparing digital equalizer outputs to prescribed equalizer outputs

A novel method of configuring a physical layer transceiver for providing data communications via residential wiring. A transmit section of the transceiver produces a pulse signal having selected amplitude. This pulse signal received by an input circuit in a receiver section of the transceiver is used for adjusting the gain of the input circuit to a fixed optimum level. In particular, the gain of the input circuit may be adjusted in response to at least one pulse. A calibration circuit of the transceiver includes a comparator for comparing the receive signal produced at the output of the input circuit, with a threshold level, and controller that supplies the input circuit with a gain control value, and sets the threshold level. The controller reduce the gain control value to decrease the gain of the input circuit when the receive signal exceeds the threshold level. The gain control value is increased to raise the gain of the input circuit when the receive signal is less than the threshold level.

Self-calibration procedure in physical layer transceiver for home telephone wire network

A network receiver is configured for receiving a modulated carrier signal from another network transceiver via a network medium, the modulated carrier signal may be either a pulse position modulated (PPM) carrier or a quadrature amplitude modulated (QAM) carrier. The network receiver is configured to select an optimal gain setting for the input amplifier corresponding to whether the modulated carrier is PPM or QAM.

Device and method for adjusting input gain for multiple signal formats in a data network

A device for modulating a carrier signal simultaneously performs frequency translation, upsampling, and pulse shaping. The device includes a mapper generating a first data signal. A complex mixer and an upsampling device are used to increase the data value frequency and spectrum shift the data signal. A finite impulse response filter operating on the data signal generates a digital signal representing the modulated carrier.

Device and method for I/Q modulation, frequency translation and upsampling

A network transmitter for generating frames of data for transmission in a compatibility mode network including frames utilizing two modulation schemes is provided. The transmitter includes a first physical layer circuit generating frames utilizing a first modulation scheme and a second physical layer circuit generating frames utilizing a second modulation scheme. The second modulation circuit retrieves a compatibility mode header from the first physical layer circuit for generating compatibility mode frames.

Compatibility mode pulse signal generation circuit and method

A pulse transmitter includes a phase correction module configured for detecting a phase error between a transmit clock and a prescribed clock specification at a transmit clock instance. The transmit clock instance represents an instance in time in which the pulse transmitter is to transmit data according to the prescribed clock specification. The pulse transmitter also includes pulse shape tables, each configured for outputting a corresponding waveform sample set of a prescribed waveform relative to a corresponding phase offset. Hence, the pulse transmitter is able to compensate for phase differences between the transmit clock utilized by the pulse transmitter and the prescribed clock specification, by outputting a selected waveform sample set that has a corresponding phase offset that compensates for the detected phase error, optimizing the performance of pulse position modulation communications systems that are adversely affected by transmit jitter.

Arrangement for reducing transmitted jitter

A network receiver is configured for receiving a modulated carrier signal representing a data frame from a network transmitter via a network medium, the receiver includes an adaptive equalizer with a finite impulse response filter for filtering the received signal. The filter utilizes a plurality filter coefficients. A cache stores a plurality of sets of coefficients for use by the filter and the equalizer selects a set of coefficients for receiving the data frame.

Network receiver utilizing pre-determined stored equalizer coefficients

A novel physical layer transceiver is provided for receiving data transmitted via residential wiring. The transceiver includes an input circuit for receiving an incoming pulse signal, and an energy detector responsive to the incoming pulse signal for producing a pulse energy value representing energy of the incoming pulse signal. An adaptive energy detector gain control circuit is responsive to the pulse energy value for adaptively controlling gain of the energy detector so as to maintain the pulse energy value at a predetermined level. The gain of the energy detector is controlled in response to at least one of access identification pulses preceding data pulses to identify the transmitting station. The adaptive energy detector gain control circuit includes a comparator for comparing a pulse energy value produced by the energy detector with a preset threshold level, and a controller for supplying the energy detector with a gain control value. The controller reduces the gain of the energy detector if the pulse energy value exceeds the threshold level, and raises the gain of the energy detector if the pulse energy value is less than the threshold level.

Adaptive energy detector gain control in physical layer transceiver for home telephone wire network

A circuit for demodulating a modulated carrier includes a sampler receiving the modulated carrier signal and generating a digital carrier signal represented by a sequence of sample values in accordance with a clock signal at a first sampling frequency. A complex mixer frequency shifts the digital carrier signal by a frequency equal to one fourth the sampling frequency to generate a frequency shifted data signal with a sampling rate at the first sampling frequency. A decimation circuit generates four decimated signals from the frequency shifted signal, each at a decimated sampling rate. A resampling circuit generates a data signal at the decimated sampling rate and at a phase independent of the clock signal.

Device and method for interpolated signal resampling between sampling clock cycles

A physical layer transceiver of a home network station connected to a telephone medium has an architecture enabling adaptation of detection circuitry based on received network signals to enable reliable recovery of data signals. The physical layer transceiver includes an input amplifier that amplifies network signals according to one of 128 gain settings set by a receiver gain control signal. A signal conditioning circuit includes an envelope detector configured for outputting an envelope of the amplified received signal, and an energy detector configured for outputting an energy signal of the amplified received signals. The envelope signal and the energy signal are supplied to slicer threshold circuits, configured for outputting noise, peak, data event and energy event signals based on noise threshold, peak threshold, data transition threshold, and energy threshold signals, respectively. A digital controller controls the input amplifier gain and the threshold values, and adjusts the gain and threshold values based on the noise event signal and the peak event signal within an access ID (AID) interval. Hence, the receiver can be optimized on a per-packet basis for receiving network signals by adjusting the receiver portion during the AID preamble phase of the data packet. Gain control may also be used by the digital controller on the transmitter portion to selectively adjust the output gain for optimizing transmission to a destination home network station.

Physical layer transceiver architecture for a home network station connected to a telephone line medium

A network receiver is configured for receiving a modulated carrier signal representing a data frame from another network transceiver via a network medium, the modulated carrier signal may be either a pulse position modulated (PPM) carrier, a quadrature amplitude modulated (QAM) carrier, or a compatibility mode frame including both PPM and QAM portions. The network receiver is configured to select an A/D sampling clock frequency corresponding to the detected frame type.

Device and method for signal sampling at multiple clock rates

A device for modulating a carrier signal comprises a mapper generating a baud rate data signal at a first data value frequency. A complex mixer and an upsampling device are used to increase the data value frequency and spectrum shift the data signal. A finite impulse response filter operating on the data signal to generate filtered first signal with characteristics that provide for reduced side band noise when the filtered signal is mixed to generate a quadrature amplitude modulated carrier.

A network receiver is configured for receiving a base band carrier signal from another network transceiver via a network medium. A variable gain amplifier generates an amplified base band signal. An A/D converter generates a sequence of sample values representing the base band signal in response to the amplified base band signal. A gain control circuit monitors the sequence of sample values for a plurality of monitoring intervals in a sample time period, determines a range for each monitoring interval, and determines a gain setting for the variable gain amplifier.

Automatic gain control device and method for base band signaling in communications

A physical layer transceiver of a home network station connected to a telephone medium has an architecture enabling adaptation of detection circuitry based on received network signals to enable reliable recovery of data signals. The physical layer transceiver includes an input amplifier that amplifies network signals according to one of three gain settings set by a receiver gain control signal. A signal conditioning circuit includes an envelope detector configured for outputting an envelope of the amplified received signal, and an energy detector configured for outputting an energy signal of the amplified received signals. The envelope signal and the energy signal are supplied to slicer threshold circuits, configured for outputting noise, peak, data event and energy event signals based on noise threshold, peak threshold, data transition threshold, and energy threshold signals, respectively. A digital controller controls the input amplifier gain and the threshold values, and adjusts the gain and threshold values based on the noise event signal and the peak event signal within an access ID (AID) interval. In particular, the digital controller adjusts the input amplifier gain during a first part of the AID interval, and adjusts the peak threshold and the data transition threshold during a second part of the AID interval by using the slicer threshold circuits for ternary searching of the peak of the detected envelope signal.

Apparatus and method for adjusting an input gain and comparator threshold value within an access identifier interval on a telephone line medium

A method for demodulating a modulated carrier includes sampling the modulated carrier with an A/D converter clocking at a first sampling frequency to generate a modulated carrier series of samples occurring at the first sampling frequency. The first sampling frequency it selected to optimize a digital signal processor (DSP) design from demodulating a carrier modulated in accordance with a first transmission specification to recover base band data. The method includes generating a second series of samples occurring at a second sampling frequency representing the base band data. The second series of samples is calculated from the first series of samples and the second sampling frequency is selected to optimal a DSP design for recovering data from the base band data signal encoded in accordance with a second transmission specification.

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Sunnyvale, CA, United States of America

Colin D Nayler