Patent ID: 8194785

Claim:
A polar transmitter comprising: a digital processor operable to produce an outgoing modulated signal; a translational loop operable to produce an outgoing modulated Radio Frequency (RF) signal based upon the outgoing modulated signal; a power amplifier operable to produce an amplified outgoing modulated RF signal based upon the outgoing modulated RF signal and an amplifier input; a polar transmitter envelope signal path comprising: an envelope detector operable to produce an envelope signal based upon the outgoing modulated signal; and a delay block operable to produce the amplifier input based upon the envelope signal and a delay error signal; a delay calibrator comprising: a down-converter operable to produce a feedback signal based upon the amplified outgoing modulated RF signal; a filter block operable to filter the feedback signal; a delay calibrator envelope detector operable to produce a feedback envelope signal based on the filtered feedback signal; and summing node operable to produce the delay error signal based on a difference between the feedback envelope signal and the envelope signal.