Fast Algorithms for the Delay Estimation in Digital Predistortion System

In this letter, two methods are introduced for the efficiency enhancement of the delay estimation in the digital predistortion (DPD) system. The frequency multiplication (FM) method, which has less computation complexity than traditional cross-correlation method, is used for the coarse alignment of the DPD system. The parabolic curve fitting (PCF) method, which can eliminate up-sampling and filtering operations, is used for the fine alignment. The final experiment result shows that new methods can efficiently improve the delay estimation efficiency of the DPD system with almost the same estimate precision as the traditional delay estimation methods.