RADIO FREQUENCY SYSTEM WITH SWITCH TO RECEIVE ENVELOPE

• US 20180041170A1
• Filed: 08/07/2017
• Published: 02/08/2018
• Est. Priority Date: 08/08/2016
• Status: Active Grant

• Current Assignee: Skyworks Solutions Incorporated
• Original Assignee: Skyworks Solutions Incorporated
• Inventors: Zhu, Yu, Klimashov, Oleksiy, Wang, Hailing, Bartle, Dylan Charles, DiCarlo, Paul T.
• Granted Patent: US 9,973,148 B2
• Time in Patent Office: Days
• CPC Class Codes: G10H 1/057 by envelope-forming circuits
• CPC Class Codes: H02M 1/0045 Converters combining the concepts of switch-mode regulation and linear regulation, e.g. linear pre-regulator to switching converter, linear and switching converter in parallel, same converter or same transistor operating either in linear or switching mode
• CPC Class Codes: H03F 1/0222 by using a signal derived from the input signal
• 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 2200/102 A non-specified detector of a signal envelope being used in an amplifying circuit
• 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 2203/7236 the gated amplifier being switched on or off by putting into parallel or not, by choosing between amplifiers by (a ) switch(es)
• CPC Class Codes: H03F 2203/7239 the gated amplifier being switched on or off by putting into parallel or not, by choosing between amplifiers and shunting lines by one or more switch(es)
• CPC Class Codes: H03F 3/193 with field-effect devices H03F3/195 takes precedence
• CPC Class Codes: H03F 3/2171 with field-effect devices H03F3/2173 - H03F3/2178 take precedence
• CPC Class Codes: H03F 3/245 with semiconductor devices only
• CPC Class Codes: H03K 17/08122 in field-effect transistor switches
• CPC Class Codes: H03K 17/102 in field-effect transistor switches
• CPC Class Codes: H03K 17/162 without feedback from the output circuit to the control circuit
• CPC Class Codes: H03K 17/284 in field effect transistor switches
• CPC Class Codes: H03K 17/693 Switching arrangements with several input- or output-terminals, e.g. multiplexers, distributors logic circuits H03K19/00; code converters H03M5/00, H03M7/00
• CPC Class Codes: H03K 2217/0054 Gating switches, e.g. pass gates
• CPC Class Codes: H04B 1/04 Circuits
• CPC Class Codes: H04B 2001/0408 with power amplifiers
• CPC Class Codes: H04B 2001/045 with means for improving efficiency

Abstract

Aspects of this disclosure relate to a radio frequency system that includes an envelope generator configured to generate an envelope signal corresponding to an envelope of a radio frequency signal and at least two radio frequency components coupled to the envelope generator. One of the radio frequency components is a radio frequency switch configured to pass the radio frequency signal. The radio frequency switch is configured to receive the envelope signal to cause intermodulation distortion associated with the radio frequency switch to be reduced.

Claims

1. A power amplifier system comprising:

an envelope generator configured to generate an envelope signal corresponding to an envelope of a radio frequency signal;

a power amplifier coupled to the envelope generator, the power amplifier configured to amplify a radio frequency signal and to receive a power amplifier supply voltage that is based on the envelope of the radio frequency signal; and

a radio frequency switch coupled to an output of the power amplifier, the radio frequency switch configured to receive the envelope signal from the envelope generator to cause intermodulation distortion associated with the radio frequency switch to be reduced.

2. The power amplifier system of claim 1 wherein the radio frequency switch includes a field effect transistor having a body configured to receive the envelope signal.

3. The power amplifier system of claim 1 wherein the radio frequency switch includes a field effect transistor having a gate configured to receive the envelope signal superimposed on a direct current control signal.

4. The power amplifier system of claim 1 wherein the envelope generator is configured to adjust a phase of the envelope signal.

5. The power amplifier system of claim 4 wherein the envelope generator is configured to adjust a magnitude of the envelope signal.

6. The power amplifier system of claim 1 wherein the envelope generator is configured to adjust a magnitude of the envelope signal.

7. The power amplifier system of claim 1 wherein the envelope generator is configured to generate the envelope signal from a baseband signal.

8. The power amplifier system of claim 1 further comprising an envelope tracking modulator configured to generate the power amplifier supply voltage, the power amplifier being coupled to the envelope generator by way of the envelope tracking modulator.

9. The power amplifier system of claim 1 wherein a band select switch includes the radio frequency switch.

10. The power amplifier system of claim 1 wherein an antenna switch includes the radio frequency switch.

11. The power amplifier system of claim 1 wherein a transmit/receive switch includes the radio frequency switch.

12. A radio frequency system comprising:

an envelope generator configured to generate an envelope signal corresponding to an envelope of a radio frequency signal;

a radio frequency switch configured to pass the radio frequency signal, the radio frequency switch configured to receive the envelope signal to cause intermodulation distortion associated with the radio frequency switch to be reduced; and

an other radio frequency component coupled to the envelope generator.

13. The radio frequency system of claim 12 wherein the other radio frequency component is a power amplifier configured to receive a supply voltage that is based on the envelope of the radio frequency signal.

14. The radio frequency system of claim 12 wherein the other radio frequency component includes a second radio frequency switch.

15. The radio frequency system of claim 14 wherein the radio frequency switch and the second radio frequency switch are both included in a signal path between a power amplifier and an antenna port.

16. A method of switching a radio frequency signal with improved linearity, the method comprising:

generating, with an envelope generator, an envelope signal corresponding to an envelope of a radio frequency signal;

providing a power amplifier supply voltage to a power amplifier that is coupled to the envelope generator by way of an envelope tracking modulator;

applying the envelope signal to a radio frequency switch configured to receive the radio frequency signal from the power amplifier; and

switching the radio frequency signal using the radio frequency switch during said applying so as to reduce intermodulation distortion associated with the radio frequency switch.

17. The method of claim 16 wherein said applying includes applying the envelope signal to a control terminal of the radio frequency switch.

18. The method of claim 16 wherein the radio frequency switch includes a field effect transistor and said applying includes applying the envelope signal to a body of the field effect transistor.

19. The method of claim 16 further comprising adjusting a phase of the envelope signal applied to the radio frequency switch relative to a phase of a signal from the envelope generator from which the envelope tracking modulator generates the power amplifier supply voltage.

20. The method of claim 19 further comprising adjusting a magnitude of the envelope signal applied to the radio frequency switch relative to a magnitude of the signal from the envelope generator from which the envelope tracking modulator generates the power amplifier supply voltage.