Digital predistortion using feedback signal with incomplete spectral information

Power amplifiers(PAs) are nonlinear in nature and digital predistortion (DPD) often is used to compensate the nonlinearity of PAs. Generally, digital predistortion needs the bandwidth of feedforward and feedback signal several times higher than the transmission bandwidth to achieve reasonable good linearization performance. To reduce the bandwidth requirement on feedback signal path a novel approach, in which the coefficients would be approached step by step, is presented in this paper. Through optimizing the parameters the impact on linearization performance caused by feedback signal with incomplete spectral information can be significantly alleviate.