RF power transmission, modulation, and amplification embodiments

• US 7,932,776 B2
• Filed: 12/23/2009
• Issued: 04/26/2011
• Est. Priority Date: 10/22/2004
• Status: Active Grant

• Current Assignee: ParkerVision, Inc.
• Original Assignee: ParkerVision, Inc.
• Inventors: Rawlins, Gregory S., Sorrells, David F., Rawlins, Michael W.
• Primary Examiner(s): Nguyen; Khanh V
• Application Number:
  US12/646,091
• Publication Number:
  US 20100097138A1
• Time in Patent Office: 489 Days
• Field of Search: 330/2, 330/124.R, 330/149, 330/295, 455/114.2, 455/114.3, 455/127.3
• US Class Current: 330/2
• CPC Class Codes: H03F 1/02 Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation
• CPC Class Codes: H03F 1/0205 in transistor amplifiers
• CPC Class Codes: H03F 1/0211 with control of the supply voltage or current
• CPC Class Codes: H03F 1/0261 with control of the polarisation voltage or current, e.g. gliding Class A
• 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 2200/102 A non-specified detector of a signal envelope being used in an amplifying circuit
• CPC Class Codes: H03F 2201/3206 Multiple channels are combined and amplified by only one amplifier
• CPC Class Codes: H03F 3/211 using a combination of several amplifiers H03F3/60 takes precedence
• CPC Class Codes: H03F 3/24 of transmitter output stages
• CPC Class Codes: H03F 3/38 DC amplifiers with modulator at input and demodulator at output; Modulators or demodulators specially adapted for use in such amplifiers switched capacitor amplifiers H03F3/005
• CPC Class Codes: H03G 3/3042 in modulators, frequency-changers, transmitters or power amplifiers transmission power control in bidirectional transmission systems H04W52/04
• CPC Class Codes: H04B 1/04 Circuits

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. An apparatus for RF power transmission, modulation, and amplification, comprising:

a digital control module that generates a plurality of control signals;

vector modulation circuitry that generates a plurality of substantially constant envelope signals using at least said control signals and a frequency reference signal;

a power amplifier that amplifies and combines said substantially constant envelope signals to create an output signal; and

control circuitry that controls said power amplifier to transition among amplifier operational classes, wherein said control circuitry controls one or more of phases of said substantially constant envelope signals, amplitudes of said substantially constant envelope signals, and biasing inputs to said power amplifier to cause said power amplifier to transition among said amplifier operation classes.

2. The apparatus of claim 1, wherein said control circuitry controls said power amplifier according to a waveform trajectory of said output signal.

3. The apparatus of claim 1, wherein said control circuitry causes said power amplifier to traverse from a switching amplifier to a substantially linear amplifier as a waveform envelope of said output signal decreases from its maximum value towards zero.

4. The apparatus of claim 1, wherein said control circuitry causes said power amplifier to traverse to a substantially linear amplifier at a zero crossing of a waveform envelope of said output signal.

5. The apparatus of claim 1, wherein said control circuitry causes said power amplifier to traverse to a higher amplifier operational class as a waveform envelope of said output signal increases from a zero crossing of said waveform envelope.

6. The apparatus of claim 1, where said control circuitry controls said amplitudes of said substantially constant envelope signals, pursuant to a transfer function.

7. The apparatus of claim 1, where said control circuitry controls said biasing inputs to said power amplifier, pursuant to a transfer function.

8. The apparatus of claim 1, wherein said control circuitry causes said power amplifier to transition to a substantially linear amplifier by controlling drive level and bias of said power amplifier such that an output current conduction angle is equal to 360 degrees.

9. The apparatus of claim 1, wherein said control circuitry causes said power amplifier to transition to a class AB amplifier by controlling drive level and bias of said power amplifier such that an output current conduction angle is greater than 180 degrees and less than 360 degrees.

10. The apparatus of claim 1, wherein said control circuitry causes said power amplifier to transition to a class B amplifier by controlling drive level and bias of said power amplifier such that an output current conduction angle is substantially equal to 180 degrees.

11. The apparatus of claim 1, wherein said control circuitry causes said power amplifier to transition to a class C amplifier by controlling drive level and bias of said power amplifier such that an output current conduction angle is less than 180 degrees.

12. The apparatus of claim 1, wherein said control circuitry causes said power amplifier to transition to a class D amplifier by controlling drive level and bias of said power amplifier such that said power amplifier is operated in switch mode.

13. The apparatus of claim 1, wherein said control circuitry causes said power amplifier to transition to a switching amplifier by controlling said power amplifier to generate a Pulse Width Modulated (PWM) output signal.

14. The apparatus of claim 1, wherein said control circuitry causes said power amplifier to transition among amplifier operational classes pursuant to a transfer function that varies within a spectrum of magnitude to phase shift transform functions.

15. The apparatus of claim 1, wherein said control circuitry causes said power amplifier to transition from a substantially linear amplifier to a switching amplifier.