Infineon Technologies Ag

Telefonaktiebolaget Lm Ericsson (publ)

Thomas Magesacher

Peter Singerl

Martin Mataln

Chenguang Lu

Per-Erik Eriksson

Elmar Trojer

Christian Schuberth

Andreas Wiesbauer

Miguel Berg

Martin Clara

Lajos Gazsi

Yezi Huang

David Seebacher

Eduardo Lins De Medeiros

Franz Dielacher

Jaume Rius I Riu

Peter Caldera

Thomas Pötscher

Hubert Weinberger

Per Ödling

Jörg Hauptmann

An RF transmitter arrangement using analog pre-distortion is disclosed. The arrangement includes lower bandwidth circuitry, an analog pre-distorter, and a non-linear amplifier chain. The lower bandwidth circuitry is configured to generate an analog signal. The analog pre-distorter is configured to apply a non-linear distortion to the analog original signal based on a coupled feedback signal in order to generate an RF output signal. The non-linear amplifier chain is configured to amplify the RF output signal to generate a transmission signal relative to the analog original signal. The coupled feedback signal is derived from the transmission signal.

Analog RF pre-distorter and non-linear splitter

Vector Control Entity and method therein for Disorderly Leaving Events, DLEs, causing Sudden Termination Change in a DSL system. The method comprises, when a DLE occurs on a line m in a vectored group of DSL lines, and the transmission on line m is, at least partly, continued: obtaining at least one error sample from CPEs connected to other lines in the vectored group of DSL lines, and calculating an estimate of the channel coefficients, H', changed due to the DLE. The estimate is calculated based on the at least one error sample, and thus a channel estimate is provided. The method further comprises modifying a downstream precoder, based on the channel estimate, such that retraining of the other lines in the vectored group due to the DLE is avoided. The estimate of the channel coefficients is calculated based on the model H&#x2032;=H+C&#x39b;H.

Method and arrangement in a DSL vectoring system

A non-linear pre-distortion engine maintaining constant peak power at its output is disclosed. The engine includes a compression estimator, a crest factor reduction processor, a digital pre-distorter and a power amplifier. The compression estimator is configured to generate a compression estimate based on an input signal and a feedback signal. The feedback signal is based on an RF output signal. The crest factor reduction processor is configured to reduce a crest factor of the input signal to generate a crest factor reduced signal based on the compression estimate. The digital pre-distorter is configured to apply a pre-distortion to the crest factor reduced signal after an initial phase and generate a pre-distorted signal based on pre-distortion parameters. The power amplifier is configured to amplify the pre-distorted signal to generate the RF output signal. The operation of the chain consisting of pre-distorter and power amplifier is substantially linear and the pre-distorter maintains constant peak power at its output, which eliminates unwanted avalanche or pre-distorter blow-up issues.

Devices and methods for adaptive crest factor reduction in dynamic predistortion

There is provided spectrum shaping of a signal. A frequency-domain representation of the signal to be spectrum-shaped is provided. The signal is associated with a set of constellation points having a minimum distance. A spectrum-shaped signal is determined by altering a proper subset of the constellation points while maintaining the minimum distance between all of the constellation points. The spectrum-shaped signal is transformed into a time-domain signal.

Spectrum shaping for OFDM/DMT

Transceiver device and method therein, for baseband processing of signals associated with TDD communication over wire lines. The method involves use of a single burst I/O N-point complex FFT kernel for baseband processing of receive and transmit signal blocks, where the processing involves simultaneously performing a respective FFT or IFFT of two N-sample signal blocks.

Baseband processing of TDD signals

The present disclosure relates to a low-complexity transmitter architecture that drives phase modulators with digital signals to generate a pulse width modulated (PWM) signal that is transmitted by an antenna. In some embodiments, the system has a pre-processing element that generates first and second digital control signals from a digital baseband signal. A first phase modulation component introduces a first phase shift into a first local oscillator signal based upon the first control signal and generates a first digital signal corresponding to the first phase shift. A second phase modulation component introduces a second phase shift into the first local oscillator signal based upon the second control signal and generates a second digital signal corresponding to the second phase shift. A combination element is configured to combine the first and second digital output signals to generate an RF pulse width modulated (RF-PWM) signal.

Low-complexity ACPR-enhancing digital RF MIMO transmitter

One embodiment relates to a system which includes a pre-distortion unit, a power amplifier circuit, a power amplifier model, and a parameter estimation unit. The pre-distortion unit is configured to pre-distort an input signal based on a model parameter by directly computing the model inverse in an iterative fashion, thereby providing a pre-distorted signal. The power amplifier circuit is configured to amplify the pre-distorted signal. The power amplifier model is configured to model amplification of the pre-distorted signal by the power amplifier circuit based on the pre-distorted signal and the model parameter. Based on the pre-distorted signal and an error signal, the parameter estimation unit is configured to update the model parameter provided to the pre-distortion unit and the power amplifier model. The error signal represents a difference between an output signal from the power amplifier circuit and a modeled output signal from the power amplifier model.

Device and method for adaptive digital pre-distortion

The present invention relates to a precoder for a communication system arranged to provide transmission blocks for transmission over a transmission channel based on inputted symbol blocks. The precoder is arranged to pre-distort each symbol block based on an estimate of the characteristics of the transmission channel so that the corresponding transmission block appears to be undistorted after transmission over the transmission channel. In accordance therewith, the precoder is arranged to apply Tomlinson-Harashima precoding on a sum of a first measure corresponding to predistortion so as to remove intrasymbol interference and a second measure corresponding to predistortion so as to remove intersymbol interference. The present invention further relates to a method for providing transmission blocks for transmission over a transmission channel in a communication system.

Precoder for a communication system and methods used in said communication system

The invention creates a method and a device for digitally transmitting analog signals, in which oversampling is performed in analog/digital and digital/analog converters. In this arrangement, a digital/analog conversion is performed which, in particular, is suitable for VDSL systems. A transmitted digital transmission signal () is supplied to a mixing unit () and in the mixing unit (), a receive noise signal () applied to a receive noise source terminal () is superimposed on the digital transmission signal (). An interpolation filter unit (), in combination with a subsequent noise shaping device (), provides an increase in the frequency bandwidth, resulting in suitable oversampling.

Oversampling in analog/digital and digital/analog converters

A comb filter arrangement has an integrator that outputs an input value to a signal path. The signal path includes a delay stage for adjusting the input value using a delay factor, a decimator that converts the input value into a decimated output value using a non-integral factor, a differentiator that generates an intermediate output value from the input value, and an interpolation arrangement that receives the intermediate output value and generates a decimated sequence of the output value.

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Villach, Austria

Thomas Magesacher