Adaptive Power Amplifier Linearization by Digital Pre-Distortion with Narrowband Feedback usingGenetic Algorithms

Narrowband;Predistortion;Linearization;Genetic algorithms

Sperlich, Roland ; Electrical and Computer Engineering

University:Georgia Institute of Technology

Department:Electrical and Computer Engineering

关键词: Narrowband;    Predistortion;    Linearization;    Genetic algorithms;   

Others  :  https://smartech.gatech.edu/bitstream/1853/11652/1/sperlich_roland_200508_phd.pdf

美国|英语

来源: SMARTech Repository

【 摘 要 】

This dissertation presents a study of linearization techniques that have been applied to power amplifiers in the cellular communicationindustry. The objective of this work is to understand the limitations of power amplifiers, specifically the limitations introduced by the use of spectrally efficient modulation schemes.The digitization of communication systems has favored the use of new techniques and technologies capable of increasing the efficiency of costly power amplifiers. The work explores traditional and digital linearization systems; an algorithm based on the principles of natural recombination is proposed to directly address thelimitations of previous embodiments. Previous techniques, although effective, have significant implementation costs that increase exponentially with the increasing signal bandwidths. The proposed software-hardware architecture significantly reduces implementation costs and the overall complexity of the design without sacrificing performance.To fulfill the requirements of this study, multiple systems are implemented through simulation and closed-loop hardware. Both simulation and hardware embodiments meet the expected performance metrics, providing validation of the proposed algorithm. The application of the algorithm to memory power amplifier linearization is a new approach to adaptive digital pre-distortion using narrowband feedback. The work will show performance improvements on an amplifier with memory effects suggesting that this technique can be employed as a lower-cost solution to meet requirements when compared to typical system implementations.