Dissertation in the field or signal processing, Mei Yen Cheong, Lic. Tech.
Mei Yen Cheong's disseratation takes place in Aalto University School of Electrical Engineering on Friday 25 April at 12 noon. The tile of the thesis is "Development of digital predistorters for broadband power amplifiers in OFDM systems using the simplicial canonical piecewise linear function".
Dissertation studies new techniques for mitigating distortion caused by nonlinear power amplifiers in broadband wireless communications systems. Nonlinear distortion affects the transmitted signal quality as well as causes interference to the adjacent frequency channels. These effects can be reduced by linearizing the power amplifier using an external linearizer. Predistortion is one of the commonly employed linearization methods, for which this work proposes various algorithms and architectures based on piecewise linear function with memory.
By using a piecewise linear function, it is possible to model the power amplifier and the predistorter more efficiently. Performance studies show that the methods proposed in this work can effectively compensate the effects of nonlinear power amplifiers. The results also show that the performance of the methods are comparable, and in some cases, exceeds the performance of state-of-the art predistorition methods employing polynomial structures. The techniques proposed in this work can be applied, for example, in the fourth generation wireless communication systems.
Opponents: Professori Markku Renfors (Tampere University of Technology, Finland) and Professor Paulo S. R. Diniz (Universidade Federal do Rio de Janeiro, Brazil)
Supervisor: Professor Risto Wichman, Aalto University School of Electrical Engineering Department of Signal Processing and Acoustics
Lisätiedot:
Electronic dissertation thesis (otalib.aalto.fi)