A new non-iterative, adaptive baseband predistortion method for high power rf amplifiers

In this paper a digital baseband predistorter based on a noniterative adaptation method is presented. In the proposed solution, there are no convergence constrains and the loop delay has to be estimated only once, in advance of the training process. In addition, the gain table is directly extracted in rectangular form overcoming the need of a sequential extraction of the AM/AM and AM/PM gain table, while any polar to rectangular gain transformation is eliminated. Experimental measurements of an in-house prototype of the method show a linearity improvement better than 25 dB.