A transmitter for a mobile terminal including a polar modulator that compensates for amplitude to frequency distortion (AM to FM distortion) of a power amplifier in the transmit chain is provided. In general, the modulator includes a polar converter that converts an input signal into an amplitude signal and a phase signal. A phase to frequency converter converts the phase signal into a frequency signal. Based on the amplitude signal, compensation circuitry generates a frequency compensation signal that essentially cancels that AM to FM distortion of the power amplifier. A combiner combines the frequency signal and the frequency compensation signal, and the pre-distorted signal is converted into an analog frequency signal and amplified by the power amplifier. Accordingly, when the pre-distorted signal is amplified by the power amplifier, the frequency compensation signal essentially cancels the AM to FM distortion of the power amplifier.