LUT Predistortion Based On Measured Non-Linear Characteristics of Power Amplifier

Techniques of performing the linearization for power amplifier (PA) are indispensable in wireless transmitter system. In order to compensate the distortion caused by PA, it is necessary to obtain the PA´s AM-AM and AM-PM characteristics with the latter difficult to track. In this paper, we propose two effective approaches for measuring the above two characteristics of PA. Based on the measured data, the compensation introduced by look-up table (LUT) predistorter can be evaluated by computer simulation. By eliminating the signal distortion and spectral regrowth, good linearization is achieved by this LUT technique, and it becomes better with the increase of LUT size.