Shortwave MemoryPower Amplifier Linearization Based on Multi-Directional Search Algorithm Predistorter

Shortwave power amplifiers (PAs) are nonlinearization and their features are changed with many kinds of factors such as the temperature of environmental, electrical aging, at the same time they have strong memory effection. In this paper, an indirect learning architecture and digital pre-distortion have been adopted, MDS algorithm applied in adaptive pre-distortion amplifier system of optimizes control is used as well, then in order to obtain the three harmonics of the signal as the optimization goal, the system is always in optimal working condition by continuously adjusting the coefficients of pre-distortion model. The adaptation of system can be simulated by Matalab, and the simulation results show that this algorithm is much better than the traditional algorithm, with about 20dB improvement of three times harmoric.