Power loop control based envelope tracking

1. Circuitry comprising:

configuration-feedback circuitry configured to regulate an output power from a radio frequency power amplifier based on a difference between a target output power from the radio frequency power amplifier and a measured output power from the radio frequency power amplifier; and

transceiver circuitry configured to regulate a modulated power supply voltage, which is used by the radio frequency power amplifier to provide power for amplification, based on the difference between the target output power from the radio frequency power amplifier and the measured output power from the radio frequency power amplifier, wherein:

the transceiver circuitry is further configured to provide a modulated radio frequency input signal to the radio frequency power amplifier;

the transceiver circuitry comprises a V CC look up table;

the modulated power supply voltage is based on the V CC look up table; and

a V CC look up table index signal is configured to provide an index signal into the V CC look up table that substantially emulates an input power of the modulated radio frequency input signal.

2. The circuitry of claim 1 wherein the configuration-feedback circuitry is further configured to regulate the output power from the radio frequency power amplifier, such that the measured output power from the radio frequency power amplifier is about equal to the target output power from the radio frequency power amplifier.

3. The circuitry of claim 1 wherein:

the transceiver circuitry is further configured to provide a modulated radio frequency input signal having an input power to the radio frequency power amplifier;

the radio frequency power amplifier is configured to generate an amplified radio frequency output signal based on the input power of the modulated radio frequency input signal and the modulated power supply voltage;

the measured output power from the radio frequency power amplifier is representative of the output power from the radio frequency power amplifier; and

a measured amplified radio frequency output signal is representative of the measured output power from the radio frequency power amplifier.

4. The circuitry of claim 1 further comprising the radio frequency power amplifier.

5. The circuitry of claim 1 wherein the configuration-feedback circuitry is further configured to:

receive a measured amplified radio frequency output signal;

provide a transmit-target power setting signal, which is based on a transmit-target power setting parameter; and

provide a transmit-gain setting signal, which is based on a transmit-gain setting parameter.

6. The circuitry of claim 5 wherein:

the transmit-target power setting parameter is representative of the target output power from the radio frequency power amplifier; and

the transmit-gain setting parameter is representative of a transmit-gain setting of the transceiver circuitry.

7. The circuitry of claim 5 wherein the transmit-gain setting parameter is based on the measured amplified radio frequency output signal and the transmit-target power setting parameter.

8. The circuitry of claim 5 wherein the transceiver circuitry is further configured to provide and adjust an input power of a modulated radio frequency input signal to the radio frequency power amplifier based on the transmit-target power setting parameter and the transmit-gain setting parameter.

9. The circuitry of claim 5 wherein the transceiver circuitry is further configured to adjust the transmit-gain setting parameter in response to changes in bias settings of the transceiver circuitry.

10. The circuitry of claim 5 wherein the transceiver circuitry is further configured to adjust the transmit-gain setting parameter in response to temperature changes of the transceiver circuitry.

11. The circuitry of claim 5 wherein the transceiver circuitry is further configured to adjust the transmit-gain setting parameter in response to changes in a voltage standing wave ratio associated with the radio frequency power amplifier.

12. The circuitry of claim 5 wherein the transceiver circuitry is further configured to adjust the transmit-gain setting parameter in response to changes in a transmit frequency of the radio frequency power amplifier.

13. The circuitry of claim 1 wherein an envelope tracking power converter system is configured to generate the modulated power supply voltage based on a control signal.

14. The circuitry of claim 13 further comprising the envelope tracking power converter system.

15. The circuitry of claim 1 wherein:

the transceiver circuitry is further configured to receive an I/Q signal and provide a modulated radio frequency input signal to the radio frequency power amplifier;

the modulated power supply voltage is based on the I/Q signal; and

the modulated radio frequency input signal is based on the I/Q signal.

16. The circuitry of claim 1 wherein:

the modulated power supply voltage is based on a control signal; and

the transceiver circuitry is further configured to adjust the modulated power supply voltage via the control signal to compensate for changes of a transmit-gain setting of the transceiver circuitry.

17. The circuitry of claim 1 wherein the transceiver circuitry is further configured to adjust the V CC look up table index signal in response to changes in bias settings of the transceiver circuitry.

18. The circuitry of claim 1 wherein the transceiver circuitry is further configured to adjust the V CC look up table index signal in response to temperature changes of the transceiver circuitry.

19. The circuitry of claim 1 wherein the transceiver circuitry is further configured to adjust the V CC look up table index signal in response to changes in a voltage standing wave ratio associated with the radio frequency power amplifier.

20. The circuitry of claim 1 wherein the transceiver circuitry is further configured to adjust the V CC look up table index signal in response to changes in a transmit frequency of the radio frequency power amplifier.

21. The circuitry of claim 1 wherein the transceiver circuitry is further configured to adjust the V CC look up table index signal in response to changes of a transmit-gain setting of the transceiver circuitry.

22. The circuitry of claim 1 wherein the transceiver circuitry further comprises a pseudo-envelope follower gain control circuit, which is configured to provide a gain control signal based on a transmit-gain setting of the transceiver circuitry, such that the V CC look up table index signal is based on the gain control signal.

23. The circuitry of claim 22 wherein the gain control signal is further based on a difference between a calibration transmit-gain setting of the transceiver circuitry and the transmit-gain setting of the transceiver circuitry.

24. The circuitry of claim 22 wherein the gain control signal is further based on a difference between a calibration temperature of the transceiver circuitry and a measured temperature of the transceiver circuitry.

25. The circuitry of claim 22 wherein the gain control signal is further based on a difference between a calibration transmit frequency of the radio frequency power amplifier and a transmit frequency of the radio frequency power amplifier.

26. The circuitry of claim 22 wherein the gain control signal is further based on at least one of a difference between a calibration transmit-gain setting of the transceiver circuitry and the transmit-gain setting of the transceiver circuitry, the difference between a calibration temperature of the transceiver circuitry and a measured temperature of the transceiver circuitry, and a difference between a calibration transmit frequency of the radio frequency power amplifier and a transmit frequency of the radio frequency power amplifier.

27. A method comprising:

regulating an output power from a radio frequency power amplifier based on a difference between a target output power from the radio frequency power amplifier and a measured output power from the radio frequency power amplifier;

regulating a modulated power supply voltage, which is used by the radio frequency power amplifier to provide power for amplification, based on the difference between the target output power from the radio frequency power amplifier and the measured output power from the radio frequency power amplifier;

providing a modulated radio frequency input signal to the radio frequency power amplifier;

providing a V CC look up table, wherein the modulated power supply voltage is based on the V CC look up table; and

providing an index signal into the V CC look up table that substantially emulates an input power of the modulated radio frequency input signal.