Joint compensation of I/Q impairments and PA nonlinearity in mobile broadband wireless transmitters

Bozic, M. 2016. Joint compensation of I/Q impairments and PA nonlinearity in mobile broadband wireless transmitters. PhD thesis University of Westminster Computer Science

TitleJoint compensation of I/Q impairments and PA nonlinearity in mobile broadband wireless transmitters
TypePhD thesis
AuthorsBozic, M.
Abstract

The main focus of this thesis is to develop and investigate a new possible solution for compensation of in-phase/quadrature-phase (I/Q) impairments and power amplifier (PA) nonlinearity in wireless transmitters using accurate, low complexity digital predistortion (DPD) technique. After analysing the distortion created by I/Q modulators and PAs together with nonlinear crosstalk effects in multi-branch multiple input multiple output (MIMO) wireless transmitters, a novel two-box model is proposed for eliminating those effects. The model is realised by implementing two phases which provide an optimisation of the identification of any system. Another improvement is the capability of higher performance of the system without increasing the computational complexity. Compared with conventional and recently proposed models, the approach developed in this thesis shows promising results in the linearisation of wireless transmitters. Furthermore, the two-box model is extended for concurrent dual-band wireless transmitters and it takes into account cross-modulation (CM) products. Besides, it uses independent processing blocks for both frequency bands and reduces the sampling rate requirements of converters (digital-to-analogue and analogue-to-digital). By using two phases for the implementation, the model enables a scaling down of the nonlinear order and the memory depth of the applied mathematical functions. This leads to a reduced computational complexity in comparison with recently developed models. The thesis provides experimental verification of the two-box model for multi-branch MIMO and concurrent dual-band wireless transmitters. Accordingly, the results ensure both the compensation of distortion and the performance evaluation of modern broadband wireless transmitters in terms of accuracy and complexity.

Year2016
FileBozic_Milica_thesis.pdf

Related outputs

Joint Compensation of I/Q Impairments and PA Nonlinearity for Concurrent Dual-Band Transmitters using Two-Box Model
Bozic, M. and Budimir, D. 2015. Joint Compensation of I/Q Impairments and PA Nonlinearity for Concurrent Dual-Band Transmitters using Two-Box Model. IEEE Microwave and Wireless Components Letters. 25 (5), pp. 340-342. doi:10.1109/LMWC.2015.2409771

Compensation of undesired effects in MIMO wireless transceivers
Cabarkapa, M., Bozic, M., Neskovic, N., Neskovic, A. and Budimir, D. 2012. Compensation of undesired effects in MIMO wireless transceivers. IEEE International Symposium on Antennas and Propogation and CNC//USNC/URSI National Radio Science Meeting (APS2012). Chicago, Illinois, USA 08 - 14 July 2012 IEEE . doi:10.1109/APS.2012.6348077

Evaluation of nonlinear distortion in MIMO transmitters
Bozic, M., Cabarkapa, M., Neskovic, N., Neskovic, A. and Budimir, D. 2012. Evaluation of nonlinear distortion in MIMO transmitters. 42nd European Microwave Conference (EuMC2012). Amsterdam, The Netherlands 28th October - 2nd November 2012 IEEE .

Permalink - https://westminsterresearch.westminster.ac.uk/item/9yxv7/joint-compensation-of-i-q-impairments-and-pa-nonlinearity-in-mobile-broadband-wireless-transmitters


Share this
Tweet
Email