Digital Predistortion for nonlinear RF power amplifiers
First Claim
1. A method, comprising:
- generating a digital transmit signal;
receiving a digital receive signal that is based on an amplified analog version of the digital transmit signal, wherein the amplified analog version is produced by a power amplifier having one or more nonlinear characteristics;
storing signal samples, the signal samples including (i) transmit samples based on the digital transmit signal and (i) receive samples based on the digital receive signal;
arranging sample pairs in sample pair groups, each sample pair comprising a transmit sample of the transmit samples and a receive sample of the receive samples, wherein the receive samples of the sample pairs are aligned with the corresponding transmit samples of the sample pairs;
determining representative sample pairs for at least a portion of the sample pair groups;
determining gain coefficients based on at least a portion of the signal samples, the gain coefficients being associated with respective first operational ranges of the power amplifier, wherein determining the gain coefficients comprises using the representative sample pairs;
determining predistortion values, the predistortion values including(i) first values based on the gain coefficients, the first values being associated with the first operational ranges, and(ii) one or more second values based on an extrapolation of at least two of the gain coefficients, the one or more second values being associated with respective one or more second operational ranges of the power amplifier; and
using the predistortion values to predistort digital signals to compensate for the one or more nonlinear characteristics of the power amplifier.
3 Assignments
0 Petitions
Accused Products
Abstract
Systems and techniques relating to wireless communications are described. A described technique includes generating a digital transmit signal; receiving a digital receive signal that is based on an amplified analog version of the digital transmit signal, where the amplified analog version is produced by a power amplifier having a nonlinear characteristic(s); storing signal samples; determining gain coefficients based on the signal samples, the gain coefficients being associated with respective first operational ranges of the power amplifier; determining predistortion values, and using the predistortion values to predistort digital signals to compensate for the nonlinear characteristic(s) of the power amplifier. The predistortion values can include first values based on the gain coefficients, the first values being associated with the first operational ranges, and a second value(s) based on an extrapolation of at least two of the gain coefficients, the second value(s) being associated with a respective second operational range(s) of the power amplifier.
-
Citations
23 Claims
-
1. A method, comprising:
-
generating a digital transmit signal; receiving a digital receive signal that is based on an amplified analog version of the digital transmit signal, wherein the amplified analog version is produced by a power amplifier having one or more nonlinear characteristics; storing signal samples, the signal samples including (i) transmit samples based on the digital transmit signal and (i) receive samples based on the digital receive signal; arranging sample pairs in sample pair groups, each sample pair comprising a transmit sample of the transmit samples and a receive sample of the receive samples, wherein the receive samples of the sample pairs are aligned with the corresponding transmit samples of the sample pairs; determining representative sample pairs for at least a portion of the sample pair groups; determining gain coefficients based on at least a portion of the signal samples, the gain coefficients being associated with respective first operational ranges of the power amplifier, wherein determining the gain coefficients comprises using the representative sample pairs; determining predistortion values, the predistortion values including (i) first values based on the gain coefficients, the first values being associated with the first operational ranges, and (ii) one or more second values based on an extrapolation of at least two of the gain coefficients, the one or more second values being associated with respective one or more second operational ranges of the power amplifier; and using the predistortion values to predistort digital signals to compensate for the one or more nonlinear characteristics of the power amplifier. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A system, comprising:
-
processor electronics configured to produce a digital transmit signal; a first converter to convert the digital transmit signal to an analog transmit signal; a power amplifier to amplify the analog transmit signal, wherein the power amplifier has one or more nonlinear characteristics; receiver circuitry to receive an analog receive signal; and a second converter to convert the analog receive signal to a digital receive signal, wherein the processor electronics are configured to perform operations comprising causing the receiver circuitry to receive the amplified analog transmit signal as the analog receive signal, storing signal samples, the signal samples including (i) transmit samples based on the digital transmit signal and (ii) receive samples based on the digital receive signal; arranging sample pairs in sample pair groups, each sample pair comprising a transmit sample of the transmit samples and a receive sample of the receive samples, wherein the receive samples of the sample pairs are aligned with the corresponding transmit samples of the sample pairs; determining representative sample pairs for at least a portion of the sample pair groups; determining gain coefficients based on at least a portion of the signal samples, the gain coefficients being associated with respective first operational ranges of the power amplifier, wherein determining the gain coefficients comprises using the representative sample pairs; determining predistortion values, the predistortion values including (i) first values based on the gain coefficients, the first values being associated with the first operational ranges, and (ii) one or more second values based on an extrapolation of at least two of the gain coefficients, the one or more second values being associated with respective one or more second operational ranges of the power amplifier; and using the predistortion values to predistort digital signals to compensate for the one or more nonlinear characteristics of the power amplifier. - View Dependent Claims (9, 10, 11, 12, 13, 14)
-
-
15. An apparatus, comprising:
-
circuitry configured to (i) produce signals including a digital transmit signal and (ii) receive signals including a digital receive signal that is based on an amplified analog version of the digital transmit signal, the amplified analog version being produced by a power amplifier having one or more nonlinear characteristics; and a memory to store signal samples, the signal samples including (i) transmit samples based on the digital transmit signal and (ii) receive samples based on the digital receive signal, wherein the circuitry is configured to perform operations comprising determining gain coefficients based on at least a portion of the signal samples, the gain coefficients being associated with respective first operational ranges of the power amplifier; determining predistortion values with respect to a threshold parameter, the predistortion values comprising first values and one or more second values, wherein determining the predistortion values comprises; (i) determining the first values based on the gain coefficients, the first values being associated with the first operational ranges, the first operational ranges meeting or surpassing the threshold parameter, and (ii) determining the one or more second values based on an extrapolation of at least two of the gain coefficients, the one or more second values being associated with respective one or more second operational ranges of the power amplifier, the one or more second operational ranges not surpassing the threshold parameter; and using the predistortion values to predistort digital signals to compensate for the one or more nonlinear characteristics of the power amplifier. - View Dependent Claims (16, 17, 18, 19, 20, 21, 22, 23)
-
Specification