US 8,576,941 B2 · Configurable basis-function generation for nonlinear modeling

Abstract

Digital predistorter circuits with selectable basis function configurations are described. In some embodiments, an input scaling block is introduced prior to a basis function generator structure. The input scaling factor is based on the input signal's average power. In other embodiments, configurable connection coefficients are used to construct the orthogonal basis functions. Multiple sets of tap weights for the predistorter are maintained, each set corresponding to a given basis function configuration. In an example method for pre-distorting an input signal to compensate for distortion introduced by an electronic device, a statistic characterizing the input signal is calculated, and one of a pre-determined set of basis function configurations is selected, based on the statistic. A set of pre-distortion model weights corresponding to the selected basis function configuration are determined, after which the selected basis function configuration and the corresponding set of pre-distortion model weights are applied to the input signal.

Claims23

Dependent claims

A method for compensating an input signal for distortion introduced by an electronic device operating on the input signal to produce an output signal, characterized in that the method comprises:

calculating a statistic characterizing the input signal over a selected time interval;
selecting, based on the statistic, one of a predetermined plurality of basis function configurations for a non-linear model of pre-distortion for compensating the distortion introduced by the electronic device, wherein each basis function configuration corresponds to a different basis function set;
determining a set of pre-distortion model weights corresponding to the selected basis function configuration;
applying the selected basis function configuration and the set of pre-distortion model weights to the input signal, to produce a pre-distorted input signal for input to the electronic device.

1 more element

A circuit for compensating an input signal for distortion introduced by an electronic device operating on the input signal to produce an output signal, characterized in that the circuit comprises:

a processor circuit configured to:
calculate a statistic characterizing the input signal over a selected time interval, from samples of the input signal;
select, based on the statistic, one of a predetermined plurality of basis function configurations for a non-linear model of pre-distortion for compensating the distortion introduced by the electronic device, wherein each basis function configuration corresponds to a different basis function set;
and
determine a set of pre-distortion model weights corresponding to the selected basis function configuration;
and
a pre-distortion application circuit configured to apply the selected basis function configuration and the set of pre-distortion model weights to the input signal, to produce a pre-distorted input signal for input to the electronic device.

4 more elements

Dependencies are inferred from the claim text.

Configurable basis-function generation for nonlinear modeling

Life of this patent

Configurable basis-function generation for nonlinear modeling

Life of this patent

Abstract

Claims23