Patent ID: 8738066

Claim:
An electronic device that is configured to wirelessly transmit radio-frequency signals using a plurality of cellular telephone modulation schemes, comprising: antenna structures; a transceiver that produces the radio-frequency signals for transmission; power amplifier circuitry that amplifies the radio-frequency signals for transmission of the radio-frequency signals through the antenna structures at an output power; a power detector that produces measurements of the output power; an adjustable voltage supply that supplies an adjustable power amplifier bias voltage to the power amplifier circuitry to power the power amplifier circuitry; and control circuitry that is configured to direct the adjustable voltage supply to supply the adjustable power amplifier bias voltage at a level that is adjusted in real time based at least partly on which cellular telephone modulation scheme of the plurality of cellular telephone modulation schemes is currently being used in transmitting the radio-frequency signals through the antenna structures, wherein the control circuitry includes storage that contains calibration data, wherein the calibration data includes calibration data specifying a first power amplifier bias voltage for a first operating frequency and a second power amplifier bias voltage for a second operating frequency, and wherein the first operating frequency is different from the second operating frequency.