Patent ID: 7639992

Claim:
A phase-locked loop (PLL) for use in a polar transmitter, comprising: a phase and frequency detector coupled to receive a reference signal and a feedback signal and operable to produce an error signal indicative of a difference in phase or frequency between the reference signal and the feedback signal; a charge pump coupled to receive the error signal and operable to generate a current pulse proportional to the error signal; a loop filter coupled to receive the current pulse and operable to filter the current pulse to produce a control voltage; a voltage controlled oscillator coupled to receive the control voltage and operable to produce an RF phase signal based on the control voltage; a frequency divider coupled to receive the RF phase signal and divide the RF phase signal by a divide ratio to produce the feedback signal; and a controller coupled to receive a corrected digital phase signal produced from a combination of a digital phase-modulated signal of a complex modulated digital signal and a phase correction signal that compensates for nonlinearities in the charge pump, said controller being operable to set the divide ratio based on the corrected digital phase signal; wherein the voltage controlled oscillator is operable to track the phase of the digital phase-modulated signal based on the control voltage to produce the RF phase signal.