Autonomous predistortion calibration of an RF power amplifier

A novel built-in calibration mechanism for a nonlinear digitally-controlled power amplifier (DPA), or its combination with an external power amplifier (PA), is proposed. It allows construction of a digital predistortion mechanism, which is configured based on data collected entirely through processing of internal digital signals in an all-digital PLL (ADPLL)-based transmitter. The proposed technique is suitable not only for characterizing the amplitude and phase transfer function non- linearities and configuring the internal predistortion accordingly, but may also be useful for built-in self-test (BIST) purposes. The proposed technique has been implemented and successfully validated in a commercial single-chip GSM/EDGE radio.