Predistorter design and method using stochastic gradient method and indirect learning architecture

摘要

The present invention uses a statistical gradient approximation method to modify the coefficients of a communication system, and attempts to modify coefficients for a complex structure of a precompensator having a combination of linear and nonlinear distortions, thereby improving system performance and increasing power efficiency. It is about.;According to the present invention, a first inverse linear device for compensating for the linear distortion that occurs when there is a synchronization error in the sampling process of the received signal in the reception filter, ISI (Inter-Symbol Interference); An inverse nonlinear device for compensating for nonlinear amplification occurring in the power amplifier using a phase system and a polynomial type; A second inverse linear device for compensating an ISI signal generated when linear distortion occurs in the filtering process of the pulse shaping filter; And a learning device receiving a signal from the second inverse linear apparatus and updating and feeding back a coefficient of a polynomial type used in the inverse nonlinear apparatus using a statistical gradient approximation method and an indirect learning method. Is provided.