Modeling digital predistorter
AssigneeTelefonaktiebolaget L M Ericsson (publ)
InventorChunlong Bai
Life of this patent
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Abstract
Methods and apparatus are disclosed for predistorting an input signal to compensate for non-linear distortions introduced by an electronic device, for example, a power amplifier. The non-linear effects of a power amplifier can be modeled using different behavior models. Coefficients for one behavior model can be converted into coefficients for a different behavior model using a conversion function. A conversion circuit implementing the conversion function can be used in between a predistorter and an adaptation circuit that use different models.
Claims16
A method of compensating for distortions introduced by an electronic device, comprising:
- receiving an input signal to a predistorter and an output signal from the electronic device;
- generating a first set of model coefficients based on a first predistorter model used in an adaptation circuit, the input signal to the predistorter, and the output signal;
- generating a second set of model coefficients for a second predistorter model by applying a conversion function to the first set of model coefficients, wherein the second predistorter model is used by the predistorter;
- adapting the predistorter based on the second set of model coefficients;
- and
- predistorting input signals to the predistorter based on the second predistorter model.
A circuit for compensating for distortions introduced by an electronic device to produce a predistorted input signal, wherein the electronic device operates on an input signal to a predistorter, said circuit comprising:
- an adaptation circuit configured to compute a first set of model coefficients for a first predistorter model from the input signal to the predistorter;
- a coefficient conversion circuit configured to generate a second set of model coefficients for a second predistorter model from the first set of model coefficients;
- and
- a modeling circuit configured to adapt the predistorter based on the second set of model coefficients.
Dependencies are inferred from the claim text.