Systems and methods of RF power transmission, modulation, and amplification

• US 8,884,694 B2
• Filed: 06/26/2012
• Issued: 11/11/2014
• Est. Priority Date: 06/28/2007
• Status: Active Grant

• Current Assignee: ParkerVision, Inc.
• Original Assignee: ParkerVision, Inc.
• Inventors: Sorrells, David F., Rawlins, Gregory S., Rawlins, Michael W.
• Primary Examiner(s): Pascal, Robert
• Assistant Examiner(s): NGUYEN, KHIEM D
• Application Number:
  US13/532,968
• Publication Number:
  US 20130027128A1
• Time in Patent Office: 868 Days
• Field of Search: 330/127, 330/129, 455/127.1
• US Class Current: 330/127
• CPC Class Codes: H03F 1/0211 with control of the supply voltage or current
• CPC Class Codes: H03F 1/0272 by using a signal derived from the output signal
• CPC Class Codes: H03F 1/0294 using vector summing of two or more constant amplitude phase-modulated signals
• CPC Class Codes: H03F 1/32 Modifications of amplifiers to reduce non-linear distortion by negative feedback H03F1/34
• CPC Class Codes: H03F 2200/336 A I/Q, i.e. phase quadrature, modulator or demodulator being used in an amplifying circuit
• CPC Class Codes: H03F 2200/345 Pulse density modulation being used in an amplifying circuit
• CPC Class Codes: H03F 2200/451 the amplifier being a radio frequency amplifier
• CPC Class Codes: H03F 2203/21106 An input signal being distributed in parallel over the inputs of a plurality of power amplifiers
• CPC Class Codes: H03F 3/193 with field-effect devices H03F3/195 takes precedence
• CPC Class Codes: H03F 3/211 using a combination of several amplifiers H03F3/60 takes precedence

Abstract

Methods and systems for vector combining power amplification are disclosed herein. In one embodiment, a plurality of signals are individually amplified, then summed to form a desired time-varying complex envelope signal. Phase and/or frequency characteristics of one or more of the signals are controlled to provide the desired phase, frequency, and/or amplitude characteristics of the desired time-varying complex envelope signal. In another embodiment, a time-varying complex envelope signal is decomposed into a plurality of constant envelope constituent signals. The constituent signals are amplified equally or substantially equally, and then summed to construct an amplified version of the original time-varying envelope signal. Embodiments also perform frequency up-conversion.

Claims

1. A method of amplifier class control, comprising:

determining a desired class of operation of an amplifier based on a power level of an output waveform;

operating the amplifier in the desired class of operation by biasing the amplifier into a non-linear switch mode;

determining a modified class of operation based on a change in the power level of the output waveform; and

operating the amplifier in the modified class of operation.

2. The method of claim 1, wherein the amplifier comprises a multiple input single output (MISO) amplifier.

3. The method of claim 1, wherein the desired class of operation is determined such that a power efficiency is optimized for the power level of the output waveform.

4. The method of claim 1, wherein the desired class of operation is determined such that a linearity of the amplifier is optimized for power level of the output waveform.

5. The method of claim 1, wherein the power level of the output waveform is an instantaneous power level.

6. The method of claim 5, wherein the instantaneous power level is determined as a function of a desired output waveform envelope.

7. The method of claim 1, wherein the power level of the output waveform is an average power level.

8. The method of claim 1, wherein the desired class of operation is determined based on a desired type of output waveform.

9. The method of claim 1, wherein operating the amplifier in the modified class of operation comprises biasing the amplifier in a modified non-linear switch mode.

10. The method of claim 1, further comprising controlling a phase of the output waveform based on the desired class of operation or the modified class of operation.

11. An apparatus, comprising:

an amplifier; and

an amplifier controller configured to;

determine a desired class of operation of an amplifier based on a power level of an output waveform,

operate the amplifier in the desired class of operation by biasing the amplifier into a non-linear switch mode,

determine a modified class of operation based on a change in the power level of the output waveform, and

operate the amplifier in the modified class of operation.

12. The apparatus of claim 11, wherein the amplifier comprises a multiple input single output (MISO) amplifier.

13. The apparatus of claim 11, wherein the desired class of operation is determined such that a power efficiency is optimized for the power level of the output waveform.

14. The apparatus of claim 11, wherein the desired class of operation is determined such that a linearity of the amplifier is optimized for power level of the output waveform.

15. The apparatus of claim 11, wherein the power level of the output waveform is an instantaneous power level.

16. The apparatus of claim 15, wherein the instantaneous power level is determined as a function of a desired output waveform envelope.

17. The apparatus of claim 11, wherein the power level of the output waveform is an average power level.

18. The apparatus of claim 11, wherein the desired class of operation is determined based on a desired type of output waveform.

19. The apparatus of claim 11, wherein the amplifier controller is configured to operate the amplifier in the modified class of operation by biasing the amplifier in a modified non-linear switch mode.

20. The apparatus of claim 11, wherein the amplifier controller is further configured to control a phase of the output waveform based on the desired class of operation or the modified class of operation.