Cartesian augmented Hammerstein model for non-linearity and I/Q impairments compensation in concurrent dual-band transmitters

摘要

In this study, a novel model for the joint compensation of dual-band power amplifier (PA) distortion and in-phase/quadrature (I/Q) imbalance, which are the dominant impairments of wireless signal transmitters, in a complexity reduced structure is proposed. This model is mainly based on the augmented Hammerstein approach in a Cartesian form so that a static block is intended to model the PA non-linearity and the modulator I/Q imbalance while a finite impulse response filter based block is used to model the PA memory effects. The proposed approach reduces significantly the complexity of the proposed model compared with the recently published memory polynomial models. Experiments with and without I/Q modulator impairments have been carried out on a dual-band PA to verify the accuracy and the performance of the linearisation technique based on the proposed model. The experimental results have revealed a good impairments reduction with much less model coefficients compared with the recently published ones.