Design And Implementation Of A Baseband Predistorter For Hf High Power Amplifier

In order to reduce the distortion caused by the nonlinear characteristics of power amplifier (PA) in the communication system, the measurement system is built to measure nonlinear characteristics of the power amplifier. The obtained nonlinear characteristic curve is modelled with polynomial and the baseband predistorter based on look-up table is designed and implemented. Experimental results show that the nonlinear characteristic of the PA is compensated with the baseband predistorter, and the three order intermodulation caused by the nonlinearity of the investigated PA is decreased about 36dB.