AMPLIFIER SYSTEM EMPLOYING ANALOG POLYNOMIAL PREDISTORTION WITH SUB-NYQUIST DIGITAL ADAPTATION

摘要

A predistortion linearized amplifier system that uses analog polynomial based predistortion is disclosed. An analog polynomial function generator (110) receives polynomial parameter updates from a polynomial parameter generator (155). The polynomial parameter generator (155) uses a combination of analog and digital signal processing to create the parameter updates. This processing is performed on input signal amplitude, detected using analog circuits, and RF coupled samples of the input signal, and the output signal. By using a combination of analog and digital signal processing means, digital processing can be performed at sub-Nyquist rates, significantly reducing the cost of digital circuits. Also, since the predistortion modulation signal is created with an analog function generator, time correlating delay is minimized reducing circuit costs.