AMPLIFIER PHASE DISTORTION CORRECTION BASED ON AMPLITUDE DISTORTION MEASUREMENT

• US 20140266432A1
• Filed: 03/17/2014
• Published: 09/18/2014
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Qorvo International Pte. Ltd. (Qorvo, Inc.)
• Original Assignee: RF Micro Devices Incorporated (Qorvo, Inc.)
• Inventors: Scott, Baker, Shi, Ying, Maxim, George, Smith, Malcolm, Ho, Daniel
• Granted Patent: US 9,391,565 B2
• Time in Patent Office: Days
• US Class Current: 330/149
• CPC Class Codes: H01F 27/28 Coils; Windings; Conductive connections
• CPC Class Codes: H01F 27/385 for reducing harmonics
• CPC Class Codes: H03F 1/22 by use of cascode coupling, i.e. earthed cathode or emitter stage followed by earthed grid or base stage respectively
• CPC Class Codes: H03F 1/32 Modifications of amplifiers to reduce non-linear distortion by negative feedback H03F1/34
• CPC Class Codes: H03F 1/3241 using predistortion circuits H03F1/3211, H03F1/3217 take precedence
• CPC Class Codes: H03F 1/34 Negative-feedback-circuit arrangements with or without positive feedback H03F1/02 - H03F1/30, H03F1/38 - H03F1/50, H03F3/50 take precedence ; for rejection of common mode signals H03F3/45479
• CPC Class Codes: H03F 3/19 with semiconductor devices only
• CPC Class Codes: H03F 3/195 in integrated circuits
• CPC Class Codes: H03F 3/211 using a combination of several amplifiers H03F3/60 takes precedence
• CPC Class Codes: H03F 3/213 in integrated circuits
• CPC Class Codes: H03H 7/09 Filters comprising mutual inductance
• CPC Class Codes: H03H 7/1775 Parallel LC in shunt or branch path H03H7/1791 takes precedence

Abstract

This application discloses correction circuitry for correcting a phase distortion in an amplification circuit by measuring an amplitude distortion and controlling a phase shifting component based upon the measured amplitude distortion. In one embodiment, a first amplitude distortion sensor is coupled to a first node of an amplification circuit, and a first phase shifter is coupled to a second node of the amplification circuit. Additionally, a first control circuit is coupled to the first amplitude sensor and to the first phase shifter. The first control circuit is configured to correlate a first amplitude distortion measured by the first amplitude distortion sensor to a first inferred phase distortion, and to generate a first phase correction signal based upon the first inferred phase distortion, and is configured to send the first phase correction signal towards the first phase shifter.

Claims

1. A correction circuit for correcting a nonlinearity in an amplification circuit, the correction circuit comprising:

a first amplitude distortion sensor coupled to a first node of the amplification circuit; and

a first phase shifter coupled to a second node of the amplification circuit.

2. The correction circuit of claim 1, further comprising:

a first control circuit coupled to the first amplitude distortion sensor and coupled to the first phase shifter.

3. The correction circuit of claim 2, wherein the first control circuit is configured to correlate a first amplitude distortion measured by the first amplitude distortion sensor to a first inferred phase distortion.

4. The correction circuit of claim 2, wherein the first control circuit is further configured to generate a first phase correction signal based upon a first inferred phase distortion, and is configured to send the first phase correction signal towards the first phase shifter.

5. The correction circuit of claim 1, wherein the first phase shifter is coupled to the first amplitude distortion sensor.

6. The correction circuit of claim 5, wherein the first amplitude distortion sensor is configured to detect a first saturation.

7. The correction circuit of claim 6, wherein the first phase shifter is configured to shift a first phase upon detection of the first saturation by the first amplitude distortion sensor.

8. The correction circuit of claim 1, wherein:

the amplification circuit includes a first transistor having a drain, a gate, and a source;

the first amplitude distortion sensor is configured to sense the drain of the first transistor, and is configured to send a first amplitude distortion sensor control signal to the first phase shifter; and

the first phase shifter is coupled to the gate of the first transistor, and is configured to correct a first phase distortion caused by of the first transistor.

9. The correction circuit of claim 8, wherein the first phase shifter is a first varactor.

10. The communication circuit of claim 9, further comprising:

a second transistor stacked with the first transistor.

11. The correction circuit of claim 5, further comprising:

a second amplitude distortion sensor coupled to a third node of the amplification circuit; and

a second phase shifter coupled to a fourth node of the amplification circuit, and

wherein the second phase shifter is coupled to the second amplitude distortion sensor.

12. The correction circuit of claim 11, wherein:

the first amplitude distortion sensor and the first phase shifter form at least a portion of a first feedback loop; and

the second amplitude distortion sensor and the second phase shifter form at least a portion of a second feedback loop.

13. The correction circuit of claim 11, wherein:

the first amplitude distortion sensor and the first phase shifter form at least a portion of a first feedback loop; and

the second amplitude distortion sensor and the second phase shifter form at least a portion of a first feed forward loop.

14. The correction circuit of claim 11, wherein:

the first amplitude distortion sensor and the first phase shifter form at least a portion of a first feed forward loop; and

the second amplitude distortion sensor and the second phase shifter form at least a portion of a second feed forward loop.

21. The correction circuit of claim 5, wherein the first amplitude distortion sensor is a true transconductance saturation detector.

15. A communication circuit comprising:

an amplification circuit; and

a correction circuit including;

a first amplitude distortion sensor coupled to the amplification circuit,

a first control circuit coupled to the first amplitude distortion sensor, and

a first phase shifter coupled to the first control circuit and coupled to the amplification circuit.

16. The communication circuit of claim 15, wherein the amplification circuit comprises:

a first transistor having a drain, a gate, and a source; and

a second transistor having a drain, a gate, and a source, and

wherein the second transistor is stacked above the first transistor.

17. The communication circuit of claim 16, wherein:

the first amplitude distortion sensor is coupled to the amplification circuit at the drain of the first transistor; and

the first phase shifter is coupled to the amplification circuit at the gate of the first transistor.

18. The communication circuit of claim 17, further comprising:

a second phase shifter coupled the first control circuit and coupled to the gate of the second transistor.

19. The communication circuit of claim 18, further comprising:

a second amplitude distortion sensor coupled to the source of the second transistor and coupled to the first control circuit.

20. The communication circuit of claim 19, further comprising:

a third phase shifter coupled to the first control circuit and coupled to the drain of the second transistor.

22. A communication circuit comprising:

an amplification circuit including;

a first transistor having a drain, a gate, and a source; and

a second transistor having a drain, a gate, and a source, wherein the second transistor is stacked above the first transistor, and

a correction circuit including;

a first amplitude sensor coupled to the drain of the second transistor, and coupled to the gate of the first transistor, and configured to provide feedback from the drain of the second transistor to the gate of the first transistor.

23. The communication circuit of claim 22, further comprising:

an acceleration circuit coupled to the first amplitude sensor, and configured to provide an accelerated signal;

a first phase shifter configured to receive the accelerated signal and configured to correct a phase shift of the amplification circuit.

24. A communication circuit comprising:

an amplification circuit including;

a first transistor having a drain, a gate, and a source; and

a second transistor having a drain, a gate, and a source, wherein the second transistor is stacked above the first transistor, and

a correction circuit including;

a first pre-saturation sensor coupled to the drain of the first transistor; and

a first phase shifter coupled to the first pre-saturation sensor and coupled to the gate of the first transistor.

25. The communication circuit of claim 24, wherein the correction circuit further includes:

a first true saturation sensor coupled to the drain of the first transistor and coupled to the first phase shifter.

26. The communication circuit of claim 24, wherein the correction circuit further includes:

a second pre-saturation sensor coupled to the drain of the first transistor; and

a second phase shifter coupled to the second pre-saturation sensor and coupled to the gate of the second transistor.

27. The communication circuit of claim 26, further comprising:

a third phase shifter coupled to the second pre-saturation sensor and coupled to the drain of the second transistor.

28. A correction circuit for correcting a nonlinearity in an amplification circuit, the correction circuit comprising:

a first device saturation detector coupled to a first node of the amplification circuit; and

a first phase shifter coupled to a second node of the amplification circuit.