Digital Predistortion using Feedback Signal with Incomplete Spectral Information

Power amplifiers are nonlinear in nature and digital predistortion is often used to compensate the nonlinearity of PAs. Generally, digital predistortion needs 3 to 5 times feedforward and feedback bandwidth of the transmission bandwidth to achieve reasonable good linearization performance. To reduce the bandwidth requirement on feedback signal path a novel algorism, in which the coefficients would be approached step by step, is presented in this paper. Through turning and optimizing the algorithm parameters one is able to significantly alleviate the impact on linearization performance caused by feedback signal with incomplete spectral information. Index Terms -- Linearization, digital predistortion, iterative methods, incomplete spectral information, power amplifiers.