Method and apparatus for power supply modulation of a radio frequency signal

摘要

A transmitter power supply modulates an RF signal without needing to run a calibration/training cycle every time an exciter or PA module is switched in and out or every time the transmitter powers up. During calibration of the exciter module, an exciter module delay factor is determined, and stored in the exciter module, for each signal modulation scheme that may be implemented by the exciter module. During calibration of a power amplifier (PA) module, a power supply modulation (PSM) delay factor is determined for, and stored in, the PA module. During transmitter operation, the exciter module generates RF and envelope signals based on an input signal. The PA module generates a power supply voltage based on the envelope signal and a final delay factor, which final delay factor is based on the exciter module and PSM delay factors. The PA module then modulates the RF signal using the power supply voltage.

主权项

1. A method for modulating a radio frequency signal, the method comprising:
determining an exciter module delay factor based on a signal modulation scheme, wherein the exciter module delay factor corresponds to a propagation time difference between an envelope signal path of an exciter module and an RF signal path of the exciter module; determining a power supply modulation delay factor, wherein the power supply modulation delay factor corresponds to a time delay between an application of an envelope signal to a power supply modulation circuit and a generation of a power supply voltage based on the envelope signal; determining a final delay factor based on the exciter module delay factor and the power supply modulation delay factor; generating a radio frequency signal based on an input signal; generating an envelope signal based on the input signal; generating a power supply voltage based on the envelope signal and the final delay factor; and modulating the radio frequency signal based on the power supply voltage.