Multi-dimensional error definition, error measurement, error analysis, error function generation, error information optimization, and error correction for communications systems
The present invention is related to multi-dimensional error definition, error measurement, error analysis, error function generation, error information optimization, and error correction for communication systems. Novel techniques are provided that can be applied to a myriad of applications for which an input to output transfer characteristic must be corrected or linearized. According to embodiments of the present invention, error can be described, processed, and geometrically interpreted. Compact formulations of error correction and calibration functions can be generated according to the present invention, which reduce memory requirements as well as computational time.
1. A method for calibrating an electronic system, the method comprising:
applying one or more input stimulus signals to the electronic system for a state of operation;
measuring an actual output of the electronic system for the state of operation;
generating a multi-dimensional error function, wherein the multi-dimensional error function comprises at least three dimensions and a plurality of calibration coefficients associated with a plurality of parameters that characterizes one or more actual input/output transfer characteristics of the electronic system; and
applying, with a processing unit, the plurality of calibration coefficients to the electronic system, wherein the plurality of calibration coefficients adjusts the actual input/output transfer characteristics based on the measured actual output of the electronic system to reduce a difference between the one or more actual input/output transfer characteristics of the electronic system and one or more desired input/output transfer characteristics of the electronic system.
2. The method of claim 1 , wherein generating the multi-dimensional error function comprises generating the plurality of calibration coefficients corresponding to a polynomial approximation of the multi-dimensional error function.
3. The method of claim 1 , wherein generating the multi-dimensional error function comprises characterizing one or more differences between the one or more actual input/output transfer characteristics of the electronic system and the one or more desired input/output characteristics of the electronic system for each of a plurality of states of operation of the electronic system.
4. The method of claim 1 , wherein generating the multi-dimensional error function comprises determining a plurality of parameters that affect performance of the electronic system.
5. The method of claim 1 , wherein the actual input/output transfer characteristics of the electronic system depends on the state of operation of the electronic system.
6. The method of claim 1 , wherein the electronic system is calibrated at a point of calibration within the electronic system.
7. The method of claim 6 , wherein the point of calibration is located at an output of any of one or more components of the electronic system.
8. The method of claim 6 , wherein the multi-dimensional error function characterizes one or more differences between the one or more actual input/output transfer characteristics of the electronic system and the one or more desired input/output characteristic of the electronic system at the point of calibration.
9. The method of claim 6 , wherein the electronic system comprises a vector power amplifier (VPA), and wherein the point of calibration is located at an output of the VPA.
10. The method of claim 6 , wherein the electronic system comprises a vector power amplifier (VPA), wherein the VPA comprises a Multiple Input Single Output (MISO) amplifier, and wherein the point of calibration is located at an output of the MISO amplifier.
11. The method of claim 1 , wherein the electronic system comprises a vector power amplifier (VPA), and wherein determining the state of operation of the electronic system includes determining or estimating one or more of:
VPA power supply;
VPA power gain;
VPA carrier frequency;
temperature variations;
process variations;
VPA output waveform bandwidth; and
VPA Adjacent Channel Power Ratio (ACPR).
12. The method of claim 1 , wherein the electronic system includes a vector power amplifier (VPA), and wherein calculating one or more calibration multipliers comprises calculating one or more calibration coefficients related to at least one of a gain of the VPA, phase of the VPA, or both.
13. The method of claim 1 , wherein the processing unit comprises circuitry.