Power amplifier for amplifying radio frequency signal

Patent metadata

Field	Value
Publication number	US-2016142020-A1
Application number	US-201414543635-A
Country	US
Kind code	A1
Filing date	Nov 17, 2014
Priority date	Nov 14, 2014
Publication date	May 19, 2016
Grant date	—

Abstract

Power amplifiers for amplifying a radio frequency signal are provided. The power amplifier may include an envelope tracking power supply, a carrier amplifier coupled with the envelope tracking power supply and configured to amplify the radio frequency signal, an input matching network configured to split the amplified radio frequency signal from the carrier amplifier such that one part of the amplified radio frequency signal passes along a peak amplifier path and another part of the amplified radio frequency signal passes along an impedance transformer path, a peak amplifier coupled with the envelope tracking power supply and configured to amplify the one part of the amplified radio frequency signal from the input matching network, an impedance transformer configured to perform impedance transformation on the other part of the amplified radio frequency signal from the input matching network, an output matching network configured to combine the output of the peak amplifier and the impedance transformer, wherein the peak amplifier is configured to be switched off in a lower power mode and switched on in a high power mode based at least in part on an input power level of the radio frequency signal. With the claimed solutions, more powerful and efficient power amplifiers that are capable of operating over broader frequency ranges may be achieved.

First claim

1 . A power amplifier for amplifying a radio frequency signal, comprising:
an envelope tracking power supply; a carrier amplifier coupled with the envelope tracking power supply and configured to amplify the radio frequency signal; an input matching network configured to split the amplified radio frequency signal from the carrier amplifier such that one part of the amplified radio frequency signal passes along a peak amplifier path and another part of the amplified radio frequency signal passes along an impedance transformer path; a peak amplifier coupled with the envelope tracking power supply and configured to amplify the one part of the amplified radio frequency signal from the input matching network; an impedance transformer configured to perform impedance transformation on the other part of the amplified radio frequency signal from the input matching network; an output matching network configured to combine the output of the peak amplifier and the impedance transformer, wherein the peak amplifier is configured to be switched off in a lower power mode and switched on in a high power mode based at least in part on an input power level of the radio frequency signal.

2 . The power amplifier according to claim 1 , wherein the output of the envelope tracking power supply is a combination of an alternating current component and a direct current component, and wherein the alternating current component is provided by a linear modulator of the envelope tracking power supply and the direct current component is provided by an external direct current power supply.

3 . The power amplifier according to claim 1 , wherein the input matching network is configured to split the amplified radio frequency signal according to a ratio of an input impedance of the peak amplifier path to an input impedance of the impedance transformer path.

4 . The power amplifier according to claim 1 , wherein the input matching network is configured to split the amplified radio frequency signal according to an operation of the peak amplifier when it is switched on.

5 . The power amplifier according to claim 1 , wherein the input matching network and the output matching network are matched with each other to produce one or more resonances such that one or more LC pairs are omitted.

6 . The power amplifier according to claim 1 , wherein the input matching network and the output matching network are implemented by lumped element networks comprising lumped elements, by distributed parameters, or by a combination of both.

7 . The power amplifier according to claim 1 , wherein the one part of the amplified radio frequency signal passing along the peak amplifier path and the other part of the amplified radio frequency signal passing along the impedance transformer are mutually out of phase by an arbitrary value from 0 to 180 degree.

8 . A multi-stage power amplifier for amplifying a radio frequency signal, comprising an envelope tracking power supply and each stage comprising:
a carrier amplifier coupled with the envelope tracking power supply and configured to amplify the radio frequency signal; an input matching network configured to split the amplified radio frequency signal from the carrier amplifier such that one part of the amplified radio frequency signal passes along a peak amplifier path and another part of the amplified radio frequency signal passes along an impedance transformer path; a peak amplifier coupled with the envelope tracking power supply and configured to amplify the one part of the amplified radio frequency signal from the input matching network; an impedance transformer configured to perform impedance transformation on the other part of the amplified radio frequency signal from the input matching network; an output matching network configured to combine the output of the peak amplifier and the impedance transformer for input to a next stage, wherein the peak amplifier is configured to be switched off in a lower power mode and switched on in a high power mode based at least in part on an input power level of the radio frequency signal.

9 . The multi-stage power amplifier according to claim 8 , wherein the output of the envelope tracking power supply is a combination of an alternating current component and a direct current component, and wherein the alternating current component is provided by a linear modulator of the envelope tracking power supply and the direct current component is provided by an external direct current power supply.

10 . The multi-stage power amplifier according to claim 8 , wherein the input matching network is configured to split the amplified radio frequency signal according to a ratio of an input impedance of the peak amplifier path to an input impedance of the impedance transformer path.

11 . The multi-stage power amplifier according to claim 8 , wherein the input matching network is configured to split the amplified radio frequency signal according to an operation of the peak amplifier when it is switched on.

12 . The multi-stage power amplifier according to claim 8 , wherein the input matching network and the output matching network are matched with each other to produce one or more resonances such that one or more LC pairs are omitted.

13 . The multi-stage power amplifier according to claim 8 , wherein the input matching network and the output matching network are implemented by lumped element networks comprising lumped elements, by distributed parameters, or by a combination of both.

14 . The multi-stage power amplifier according to claim 8 , wherein the one part of the amplified radio frequency signal passing along the peak amplifier path and the other part of the amplified radio frequency signal passing along the impedance transformer are mutually out of phase by an arbitrary value from 0 to 180 degree.

15 . A method for amplifying a radio frequency signal, comprising:
amplifying the radio frequency signal using a carrier amplifier; splitting the amplified radio frequency signal from the carrier amplifier using an input matching network such that one part of the amplified radio frequency signal passes along a peak amplifier path and another part of the amplified radio frequency signal passes along an impedance transformer path; amplifying the one part of the amplified radio frequency signal from the input matching network using a peak amplifier in the peak amplifier path; performing impedance transformation on the other part of the amplified radio frequency signal using an impedance transformer in the impedance transform path; and combining the output of the peak amplifier and the impedance transformer using an output matching network, wherein the carrier amplifier and peak amplifier are powered by an envelope tracking power supply and the peak amplifier is configured to be switched off in a lower power mode and switched on in a high power mode based at least in part on an input power level of the radio frequency signal.

16 . The method according to claim 15 , wherein the output of the envelope tracking power supply is a combination of an alternating current component and a direct current component, and wherein the alternating current component is provided by a linear modulator of the envelope tracking power supply and the direct current component is provided by an external direct current power supply.

17 . The method according to claim 15 , wherein the amplified radio frequency signal is split according to a ratio of an input impedance of the peak amplifier path to an input impedance of the impedance transformer path.

Assignees

• Microsoft Corp

Inventors

• Wang Zhancang

Classifications

• H03F3/21

  with semiconductor devices only {(H03F3/245 takes precedence)} · CPC title

• H03F2200/451

  the amplifier being a radio frequency amplifier · CPC title

• H03F2200/387

  A circuit being added at the output of an amplifier to adapt the output impedance of the amplifier · CPC title

• H03F2200/222

  A circuit being added at the input of an amplifier to adapt the input impedance of the amplifier · CPC title

• H03F2200/102

  A non-specified detector of a signal envelope being used in an amplifying circuit · CPC title