Digital pre-distortion
AssigneeAnalog Devices, Inc.
InventorsGanesh Ananthaswamy, Sudheesh A. Somanathan
Life of this patent
Estimating the term…
Abstract
A pre-distortion circuit that may introduce a pre-distortion signal in a communication channel by determining a harmonic signal of the signal to be output. One or more image correction signals of the signal to be output may be determined. The one or more image correction signals may be complex conjugate signal variations of the signal to be output. The harmonic signal, the one or more image correction signals and the signal to be output may be combined into a combined output signal. The combined output signal may be transmitted to a digital-to-analog converter. The predistortion circuit may be implemented in a FPGA, an ASIC, a digital-to-analog converter, and/or a separate IC package.
Claims22
A predistortion system to generate a predistortion signal, comprising:
- a second order harmonic correction section including a first set of mixers to generate a second harmonic correction signal based on real and imaginary parts of a data signal and to generate at least one intermediate signal for the second harmonic correction signal generation;
- a third order harmonic correction section including a second set of mixers to generate a third harmonic correction signal based on the real and imaginary parts of the data signal and the at least one intermediate signal;
- an image correction section to generate an image correction signal;
- and
- an output for the predistortion signal, wherein the predistortion signal is a combination of the second harmonic correction signal, third harmonic correction signal, and the image correction signal.
A predistortion system, comprising:
- a harmonic correction module including a plurality of mixers to generate harmonic correction signals based on real and imaginary parts of an input data signal and on a set of correction coefficients selected in response to input data signal type;
- an image correction module to generate an image correction signal;
- a combiner module to combine the harmonic correction signals and the image correction signal to generate a predistortion signal.
A method of generating a predistortion signal, comprising:
- receiving a data signal, the data signal comprising a real portion and an imaginary portion;
- generating a second harmonic correction signal based on the real and imaginary portions and a first set of correction coefficients, wherein in generating the second harmonic correction signal, at least one intermediate signal is generated;
- based on the real and imaginary portions, a second set of correction coefficients, and the at least one intermediate signal, generating a third harmonic correction signal;
- generating an image correction signal;
- and
- combining the second harmonic correction signal, the third harmonic correction signal, and the image correction signal to generate the predistortion signal.
Dependencies are inferred from the claim text.