Arbitrary waveform predistortion table generation
First Claim
1. A method of determining predistortion that will compensate for distortion introduced by a power amplifier circuit, the method comprising:
- applying a time-varying reference signal to the power amplifier circuit, wherein at each moment the time-varying reference signal has a reference amplitude and a reference phase;
measuring a corresponding output signal supplied by the power amplifier circuit, wherein at each moment the output signal has a measured amplitude and a measured phase;
determining amplitude predistortion by comparing the reference amplitude with the measured amplitude;
determining phase predistortion by comparing the reference phase with the measured phase; and
determining a relationship between the phase predistortion and the reference amplitude such that, for any value of the reference amplitude, a corresponding value of the phase predistortion is identified,wherein;
the amplitude predistortion is associated with a range of measured amplitude values; and
the method further comprises extracting representative points from the amplitude predistortion by performing;
dividing the range of measured amplitude values into a number of intervals; and
for each of the intervals, determining an average amplitude predistortion value and using the average amplitude predistortion values as the amplitude predistortion value associated with a measured amplitude value at the center of the interval.
1 Assignment
0 Petitions
Accused Products
Abstract
Predistortion that will compensate for distortion introduced by a power amplifier circuit is determined by applying a time-varying reference signal to the power amplifier circuit, wherein at each moment the time-varying reference signal has a reference amplitude and a reference phase. A corresponding output signal supplied by the power amplifier circuit is measured, wherein at each moment the output signal has a measured amplitude and a measured phase. Amplitude predistortion is determined by comparing the reference amplitude with the measured amplitude, and phase predistortion is determined by comparing the reference phase with the measured phase. A relationship between the phase predistortion and the reference amplitude is determined such that, for any value of the reference amplitude, a corresponding value of the phase predistortion is identified.
-
Citations
31 Claims
-
1. A method of determining predistortion that will compensate for distortion introduced by a power amplifier circuit, the method comprising:
-
applying a time-varying reference signal to the power amplifier circuit, wherein at each moment the time-varying reference signal has a reference amplitude and a reference phase; measuring a corresponding output signal supplied by the power amplifier circuit, wherein at each moment the output signal has a measured amplitude and a measured phase; determining amplitude predistortion by comparing the reference amplitude with the measured amplitude; determining phase predistortion by comparing the reference phase with the measured phase; and determining a relationship between the phase predistortion and the reference amplitude such that, for any value of the reference amplitude, a corresponding value of the phase predistortion is identified, wherein; the amplitude predistortion is associated with a range of measured amplitude values; and the method further comprises extracting representative points from the amplitude predistortion by performing; dividing the range of measured amplitude values into a number of intervals; and for each of the intervals, determining an average amplitude predistortion value and using the average amplitude predistortion values as the amplitude predistortion value associated with a measured amplitude value at the center of the interval. - View Dependent Claims (2, 3, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
-
-
5. The method of claim , further comprising:
interpolating between two average amplitude predistortion values respectively associated with adjacent first and second intervals to determine an amplitude predistortion value associated with a measured amplitude value that is in-between the centers of the first and second intervals.
-
16. An apparatus for determining predistortion that will compensate for distortion introduced by a power amplifier circuit, the apparatus comprising:
-
logic that applies a time-varying reference signal to the power amplifier circuit, wherein at each moment the time-varying reference signal has reference amplitude and a reference phase; logic that measures a corresponding output signal supplied by the power amplifier circuit, wherein at each moment the output signal has a measured amplitude and a measured phase; logic that determines amplitude predistortion by comparing the reference amplitude with the measured amplitude; logic that determines phase predistortion by comparing the reference phase with the measured phase; and logic that determines a relationship between the phase predistortion and the reference amplitude such that, for any value of the reference amplitude, a corresponding value of the phase predistortion is identified, wherein; the amplitude predistortion is associated with a range of measured amplitude values; and the apparatus further comprises logic that extracts representative points from the amplitude predistortion by performing; dividing the range of measured amplitude values into a number of intervals; and for each of the intervals, determining an average amplitude predistortion value and using the average amplitude predistortion value as the amplitude predistortion value associated with a measured amplitude value at the center of the interval. - View Dependent Claims (17, 18, 19, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30)
-
-
20. The apparatus of claim , further comprising:
logic that interpolates between two average amplitude predistortion values respectively associated with adjacent first and second intervals to determine an amplitude predistortion value associated with a measured amplitude value that is in-between the centers of the first and second intervals.
-
31. A machine storage medium having stored therein a set of program instructions for determining predistortion that will compensate for distortion introduced by a power amplifier circuit, the set of program instructions causing a processor and associated logic to perform:
-
applying a time-varying reference signal to the power amplifier circuit, wherein at each moment the time-varying reference signal has a reference amplitude and a reference phase; measuring a corresponding output signal supplied by the power amplifier circuit, wherein at each moment the output signal has a measured amplitude and a measured phase; determining amplitude predistortion by comparing the reference amplitude with the measured amplitude; determining phase predistortion by comparing the reference phase with the measured phase; and determining a relationship between the phase predistortion and the reference amplitude such that, for any value of the reference amplitude, a corresponding value of the phase predistortion is identified, wherein; the amplitude predistortion is associated with a range of measured amplitude values; and the method further comprises extracting representative points from the amplitude predistortion by performing; dividing the range of measured amplitude values into a number of intervals; and for each of the intervals, determining an average amplitude predistortion value and using the average amplitude predistortion value as the amplitude predistortion value associated with a measured amplitude value at the center of the interval.
-
Specification