Generalised twin-box model for compensation of transmitters radio frequency impairments

A novel generalised twin-box model is proposed for the mutual compensation of modulator imperfections and power amplifier (PA) distortion. It is composed of two cascaded boxes, a dual branch of simplified Volterra filters for the joint characterisation of the mild non-linear dynamic memory effects of the PA and modulator imperfections. The second box is a look-up table for characterising the highly non-linear static distortion exhibited by the PA. Hence, the proposed model has reduced complexity in comparison with the state-of-the-art models, owing to the separate identification of the dynamic and static effects of the PA. The model validation is carried out using a Class AB PA, and the proposed model showed significant improvement in performance as well as reducing the computational complexity of the model.