Systems and methods of RF power transmission, modulation, and amplification, including transfer function embodiments

• US 7,421,036 B2
• Filed: 01/16/2007
• Issued: 09/02/2008
• Est. Priority Date: 10/22/2004
• Status: Expired due to Fees

• Current Assignee: ParkerVision, Inc.
• Original Assignee: ParkerVision, Inc.
• Inventors: Rawlins, Gregory S., Sorrells, David F., Rawlins, Michael W.
• Primary Examiner(s): Tran; Khai
• Application Number:
  US11/653,409
• Publication Number:
  US 20070116145A1
• Time in Patent Office: 595 Days
• Field of Search: 375/294, 375/376, 375/354, 375/293, 375/147, 375/130, 455/214, 455/288, 455/293, 455/307
• US Class Current: 375/294
• CPC Class Codes: H03C 5/00 Amplitude modulation and angle modulation produced simultaneously or at will by the same modulating signal H03C7/00 takes precedence
• 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 1/0233 by using a signal derived from the output signal, e.g. bootstrapping the voltage supply
• 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 1/3205 in field-effect transistor amplifiers
• CPC Class Codes: H03F 1/3223 using feed-forward H03F1/3211 takes precedence
• 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 2200/387 A circuit being added at the output of an amplifier to adapt the output impedance of the amplifier
• CPC Class Codes: H03F 2200/451 the amplifier being a radio frequency amplifier
• CPC Class Codes: H03F 2201/3215 To increase the output power or efficiency
• 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
• CPC Class Codes: H03F 3/24 of transmitter output stages
• CPC Class Codes: H03F 3/245 with semiconductor devices only
• CPC Class Codes: H03F 3/45071 with semiconductor devices only
• 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
• CPC Class Codes: H04B 1/0475 with means for limiting noise, interference or distortion H04B1/0483 takes precedence
• CPC Class Codes: H04B 1/0483 : Transmitters with multiple parallel paths
• CPC Class Codes: H04B 2001/045 : with means for improving efficiency
• CPC Class Codes: H04B 2001/0491 : with frequency synthesizers, frequency converters or modulators
• CPC Class Codes: H04L 27/20 : Modulator circuits; Transmitter circuits
• CPC Class Codes: H04L 27/36 : Modulator circuits; Transmitter circuits
• CPC Class Codes: H04L 27/362 : Modulation using more than one carrier, e.g. with quadrature carriers, separately amplitude modulated H04L27/366 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. An apparatus for at least RF power amplification, comprising:

first circuitry that generates a plurality of control signals according to at least one transfer function;

second circuitry that generates a plurality of substantially constant envelope signals using at least said control signals; and

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

wherein said power amplifier transitions among a plurality of amplifier operational classes; and

wherein at least one parameter of said at least one transfer function changes as an amplifier operational class of said power amplifier changes.

2. The apparatus of claim 1, further comprising:

third circuitry that changes said at least one transfer function parameter as an amplifier operational class of said power amplifier changes.

3. The apparatus of claim 2, wherein said third circuitry changes said at least one transfer function parameter within a spectrum of magnitude to phase shift transform functions.

4. The apparatus of claim 3, wherein said spectrum of magnitude to phase shift transform functions correspond to a range of amplifier classes of operation of said power amplifier.

5. The apparatus of claim 4, wherein said range of amplifier classes of operation is bounded by amplifier operational class A and amplifier operational class S.

6. The apparatus of claim 4, wherein said range of amplifier classes of operation comprises amplifier operational classes A, AB, B, C, D, and S.

7. The apparatus of claim 6, wherein said third circuitry changes said at least one transfer function parameter using amplifier output functions of FIG. 77 corresponding to amplifier operational class transitions.

8. The apparatus of claim 2, wherein said third circuitry changes said at least one transfer function parameter using amplifier output functions corresponding to amplifier operational class A and amplifier operational class S.

9. The apparatus of claim 8, said amplifier output functions corresponding to amplifier operational class A and amplifier operational class S comprising functions shown in FIG. 76.

10. The apparatus of claim 8, wherein said third circuitry changes said at least one transfer function parameter as a function of an operational class of said power amplifier.

11. The apparatus of claim 8, wherein said third circuitry changes said at least one transfer function parameter using a function:

(1−

K)×

R(θ

)+K×

SQ(θ

), with 0≦

K ≦

1,and wherein θ

is a phase angle between said substantially constant envelope signals.

12. The apparatus of claim 1, wherein a power amplifier output pulse width varies with changes in phase angle θ

.

13. The apparatus of claim 1, wherein transistors of said power amplifier operate as switching amplifiers.

14. The apparatus of claim 2, wherein said third circuitry establishes said at least one transfer function parameter when said power amplifier operates as a switching amplifier according to a magnitude to phase shift transform:

$\mathrm{SQ}<br><br>\left(\mathrm{\theta <br><br>}\right)=A<br><br><br><br>\frac{\mathrm{\pi <br><br>}-\mathrm{\theta <br><br>}}{2<br><br><br><br>\mathrm{\pi <br><br>}}$

wherein θ

is a phase angle between said substantially constant envelope signals, and amplitude A of said substantially constant envelope signals is substantially equal.

15. The apparatus of claim 1, wherein said power amplifier emulates a summing node when it operates as a substantially linear amplifier.

16. The apparatus of claim 15, wherein transistors of said power amplifier operate as current sources when said power amplifier operates as a substantially linear amplifier.

17. The apparatus of claim 2, wherein said third circuitry establishes said at least one transfer function parameter when said power amplifier operates as a substantially linear amplifier according to a magnitude to phase shift transform:

R(θ

)=AA√

{square root over (2(1+cos(θ

)))}

wherein θ

is a phase angle between said substantially constant envelope signals, and amplitude A of said substantially constant envelope signals is substantially equal.

41. The apparatus of claim 4, wherein said range of amplifier classes of operation comprises only amplifier operational classes A and S.

42. The apparatus of claim 4, wherein said range of amplifier classes of operation comprises only amplifier operational classes A and D.

43. The apparatus of claim 4, wherein said range of amplifier classes of operation comprises only amplifier operational classes AB and C.

44. The apparatus of claim 4, wherein said range of amplifier classes of operation comprises only amplifier operational classes AB and D.

45. The apparatus of claim 4, wherein said range of amplifier classes of operation comprises only amplifier operational class A.

18. A method for at least RF power amplification, comprising:

generating a plurality of control signals according to at least one transfer function;

generating a plurality of substantially constant envelope signals using at least said control signals; and

amplifying using a power amplifier said substantially constant envelope signals to create an output signal;

wherein said power amplifier transitions among a plurality of amplifier operational classes; and

wherein at least one parameter of said at least one transfer function changes as an amplifier operational class of said power amplifier changes.

19. The method of claim 18, further comprising:

changing said at least one transfer function parameter as an amplifier operational class of said power amplifier changes.

20. The method of claim 19, wherein said at least one transfer function parameter is changed within a spectrum of magnitude to phase shift transform functions.

21. The method of claim 20, wherein said spectrum of magnitude to phase shift transform functions correspond to a range of amplifier classes of operation of said power amplifier.

22. The method of claim 21, wherein said range of amplifier classes of operation is bounded by amplifier operational class A and amplifier operational class S.

23. The method of claim 21, wherein said range of amplifier classes of operation comprises amplifier operational classes A, AB, B, C, D, and S.

24. The method of claim 23, wherein said at least one transfer function parameter is changed using amplifier output functions of FIG. 77 corresponding to amplifier operational transitions.

25. The method of claim 19, wherein said at least one transfer function parameter is changed using amplifier output functions corresponding to amplifier operational class A and amplifier operational class S.

26. The method of claim 25, said amplifier output functions corresponding to amplifier operational class A and amplifier operational class S comprising functions shown in FIG. 76.

27. The method of claim 25, wherein said at least one transfer function parameter is changed as a function of an operational class of said power amplifier.

28. The method of claim 25, wherein said at least one transfer function parameter is changed using a function:

(1−

K)×

R(θ

)+K×

SQ(θ

), with 0≦

K≦

1, and wherein θ

is a phase angle between said substantially constant envelope signals.

29. The method of claim 18, wherein a power amplifier output pulse width varies with changes in phase angle θ

.

30. The method of claim 18, wherein transistors of said power amplifier operate as switching amplifiers.

31. The method of claim 19, wherein said at least one transfer function parameter is established when said power amplifier operates as a class S amplifier according to a magnitude to phase shift transform:

$\mathrm{SQ}<br><br>\left(\mathrm{\theta <br><br>}\right)=A<br><br><br><br>\frac{\mathrm{\pi <br><br>}-\mathrm{\theta <br><br>}}{2<br><br><br><br>\mathrm{\pi <br><br>}}$

wherein θ

is a phase angle between said substantially constant envelope signals, and amplitude A of said substantially constant envelope signals is substantially equal.

32. The method of claim 18, wherein said power amplifier emulates a summing node when it operates as a substantially linear amplifier.

33. The method of claim 32, wherein transistors of said power amplifier operate as current sources when said power amplifier operates as a substantially linear amplifier.

34. The method of claim 19, wherein said at least one transfer function parameter is established when said power amplifier operates as a substantially linear amplifier according to a magnitude to phase shift transform:

R(θ

)=AA √

{square root over (2(1+cos(θ

)))}

wherein θ

is a phase angle between said substantially constant envelope signals, and amplitude A of said substantially constant envelope signals is substantially equal.

35. The method of claim 21, wherein said range of amplifier classes of operation varies from a switching mode to a substantially linear mode.

36. The method of claim 21, wherein said range of amplifier classes of operation comprises only amplifier operational classes A and S.

37. The method of claim 21, wherein said range of amplifier classes of operation comprises only amplifier operational classes A and D.

38. The method of claim 21, wherein said range of amplifier classes of operation comprises only amplifier operational classes AB and C.

39. The method of claim 21, wherein said range of amplifier classes of operation comprises only amplifier operational classes AB and D.

40. The method of claim 21, wherein said range of amplifier classes of operation comprises only amplifier operational class A.