Amplitude-modulation signal and phase-modulation signal delay adjustment for polar transmitter

A method comprising:

• generating a calibration signal to control a polar transmitter to generate a calibration transmit signal;
• receiving a result signal based on the calibration transmit signal;
• estimating an amplitude modulation/phase modulation (AMPM) delay value based at least on the result signal;
• and
• generating an adjustment signal to control an AMPM delay circuitry to delay a signal output by a digital signal processing circuitry (DSP) based at least on the estimated AMPM delay value.

A polar transmitter, comprising:

• digital signal processing circuitry (DSP) configured to process a baseband signal to generate a phase modulated local oscillator (PM LO) signal and an amplitude modulation signal,
• wherein the DSP comprises an amplitude modulation/phase modulation (AMPM) delay circuitry configured to delay, based at least on an AMPM delay value, output of a signal by the DSP;
• calibration circuitry configured to generate an adjustment signal to communicate the AMPM delay value to the AMPM delay circuitry by:
• generating a calibration signal to control the polar transmitter to generate a calibration transmit signal;
• receiving a result signal that is based on the calibration transmit signal;
• and
• estimating the AMPM delay value based at least on the result signal;
• and
• providing the adjustment signal communicating the estimated AMPM delay value to the AMPM delay circuitry.