According to an exemplary embodiment, a transmitter system includes a power amplifier receiving a supply voltage and a supply current from a power control/current detection circuit, where the power amplifier drives a load impedance. The transmitter system further includes a power correction module configured to sample the supply current and to cause a change in a control voltage, which corrects the supply voltage in response to a change in the load impedance. The supply voltage is corrected to cause the power amplifier to have a substantially constant output power. The power correction module is further configured to output a corrected peak voltage determined by an average value of the supply current. The transmitter system further includes a predistortion module configured to determine the control voltage from a product of the corrected peak voltage and an amplitude modulation component and to output the control voltage to the power control/current detection circuit.