RADIO FREQUENCY POWER AMPLIFIER INCLUDING A PULSE GENERATOR AND MATCHING NETWORK CIRCUIT

• US 20150326255A1
• Filed: 05/06/2015
• Published: 11/12/2015
• Est. Priority Date: 05/07/2014
• Status: Active Grant

• Current Assignee: NVIDIA Corporation
• Original Assignee: NVIDIA Corporation
• Inventors: Dally, William J.
• Granted Patent: US 9,660,599 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H03F 1/565 using inductive elements
• CPC Class Codes: H03F 2200/171 A filter circuit coupled to the output of an amplifier
• 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 3/193 with field-effect devices H03F3/195 takes precedence
• CPC Class Codes: H03F 3/2175 using analogue-digital or digital-analogue conversion H03F3/2173 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: H03K 2005/00052 by mixing the outputs of fixed delayed signals with each other or with the input signal
• CPC Class Codes: H03K 3/45 by the use, as active elements, of non-linear magnetic or dielectric devices
• CPC Class Codes: H04B 1/04 Circuits
• CPC Class Codes: H04B 2001/0408 with power amplifiers
• CPC Class Codes: H04L 27/3411 reducing the peak to average power ratio or the mean power of the constellation; Arrangements for increasing the shape gain of a signal set

Abstract

A system and method are provided for controlling a radio frequency (RF) power amplifier. A magnitude input and a phase input are received for transmission of a RF signal by the RF power amplifier. A digital pulse, having a center position relative to an edge of a reference clock based on the phase input and having a width based on the magnitude input, is generated. The digital pulse is filtered with a resonant matching network to produce the RF signal corresponding to the magnitude input and the phase input.

Claims

1. A method, comprising:

receiving a magnitude input and a phase input for transmission of a radio frequency (RF) signal by a RF power amplifier;

generating a digital pulse having a center position relative to an edge of a reference clock based on the phase input and having a width based on the magnitude input; and

filtering the digital pulse with a resonant matching network to produce the RF signal corresponding to the magnitude input and the phase input.

2. The method of claim 1, wherein the resonant matching network comprises a tank circuit including an inductor and a capacitor.

3. The method of claim 2, wherein a surface acoustic wave filter is coupled between the tank circuit and an antenna.

4. The method of claim 1, wherein the filtering with the resonant matching network further comprises transforming an impedance at an input to the resonant matching network to match an impedance of an antenna that is coupled to the resonant matching network.

5. The method of claim 1, wherein the filtering with the resonant matching network further comprises resonating at a frequency of the RF signal to convert the digital pulse to an analog signal.

6. The method of claim 1, wherein the digital pulse is generated during a first half of a cycle of the reference clock and further comprising:

generating, during a second half of a cycle of the reference clock, a second digital pulse having a phase displaced 0.5 UI from a phase of the first pulse and having a width equal to the first pulse; and

filtering the second digital pulse with a second resonant matching network.

7. The method of claim 6, wherein the resonant matching network and the second resonant matching network are coupled to opposing terminals of a primary winding of a transformer.

8. The method of claim 7, wherein the transformer is a transmission-line transformer.

9. The method of claim 1, further comprising:

measuring in-phase and quadrature components of the RF signal; and

computing a corrected phase input and a corrected magnitude input.

10. The method of claim 1, further comprising:

receiving new in-phase and quadrature components for a new symbol;

measuring in-phase and quadrature components of the RF signal; and

computing an error phase input and an error magnitude input based on the received in-phase and quadrature components and the measured in-phase and quadrature components.

11. The method of claim 1, wherein the magnitude input and the phase input correspond to previous in-phase and quadrature components, and further comprising:

receiving new in-phase and quadrature components for a new symbol; and

computing a difference phase input and a difference magnitude input based on the previous in-phase and quadrature components and the new in-phase and quadrature components.

12. The method of claim 1, wherein generating the digital pulse comprises:

computing a start time for the digital pulse; and

varying the start time between two different values over multiple cycles of the reference clock to increase the resolution of the start time.

13. A radio frequency (RF) power amplifier circuit, comprising:

a digital pulse generation unit configured to;

receive a magnitude input and a phase input for transmission of a RF signal; and

generate a digital pulse having a center position relative to an edge of a reference clock based on the phase input and having a width based on the magnitude input; and

a resonant matching network circuit that is coupled to the digital pulse generation unit and configured to filter the digital pulse to produce the RF signal corresponding to the magnitude input and the phase input.

14. The RF power amplifier circuit of claim 13, wherein the resonant matching network comprises a tank circuit including an inductor and a capacitor.

15. The RF power amplifier circuit of claim 14, further comprising a surface acoustic wave filter that is coupled between the tank circuit and an antenna.

16. The RF power amplifier circuit of claim 13, wherein the resonant matching network is further configured to transform an impedance at an input to the resonant matching network to match an impedance of an antenna that is coupled to the resonant matching network.

17. The RF power amplifier circuit of claim 13, wherein the resonant matching network is further configured to resonate at a frequency of the RF signal to convert the digital pulse to an analog signal.

18. The RF power amplifier circuit of claim 13, further comprising a second resonant matching network, wherein the digital pulse generation unit is further configured to:

generate the digital pulse during a first half of a cycle of the reference clock; and

generate, during a second half of a cycle of the reference clock, a second digital pulse with a phase displaced 0.5 UI from a phase of the first digital pulse and width equal to the first digital pulse, wherein the second digital pulse is filtered with the second resonant matching network.

19. The RF power amplifier circuit of claim 18, wherein the resonant matching network and the second resonant matching network are coupled to opposing terminals of a primary winding of a transformer.

20. The RF power amplifier circuit of claim 13, further comprising a detector coupled between the digital pulse generation unit and the resonant matching network and configured to:

measure in-phase and quadrature components of the RF signal; and

compute a corrected phase input and a corrected magnitude input.