For my family. iii ACKNOWLEDGEMENTS It is time to draw a period to my PhD endeavor. I feel extremely lucky to meet so many talented people during these years. I am grateful for their friendship, help, encouragement, and support. First, I would like to thank my advisor, Dr. G. Tong Zhou, for providing this opportunity for me to study at Georgia Tech. Her constant encouragement and valuable advic...

The Doherty amplifier architecture is a well known technique offering the potential to improve transmitter efficiency especially for signal protocols that exhibit high peak-toaverage power ratios. Although the Doherty approach has significant efficiency advantages, it generally must be augmented with some form of correction or linearity enhancement in the full transmitter design. Wireless infra...

Many modern communication signal formats, such as orthogonal frequency-division multiplexing (OFDM) and code-division multiple access (CDMA), have high peak-to-average power ratios (PARs). A signal with a high PAR not only is vulnerable in the presence of nonlinear components such as power amplifiers (PAs), but also leads to low transmission power efficiency. Selected mapping (SLM) and clipping...

High Efficiency Power Amplifier for Envelope Detection is presented here in this paper which uses the LDMOS power amplifier to achieve high efficiency. The main objective in this work to design a power amplifier which is more efficient when subject to various kind of situations. QAM modulation with 64 point, and Additive White Gaussian Noise Channel was used here in this work. Amplitude Modulat...

Digital predistortion (DPD) techniques are widely used to linearize of RF power amplifiers. In this article, a memory polynomial-based power has been modeled with memory order of 5 and nonlinearity order of 9. These specifications had been found suitable for advanced long-term evolution (LTE) wireless systems. A suitable DPD model was created based on the least square error minimization. Result...

Nonlinearity of a directly modulated laser diode imposes limitations in the performance of fiber based wireless access schemes. Previously, laser diode nonlinearity has been investigated in CATV related applications. In the CATV scenario, analog optoelectronic compensation schemes have been widely attempted due to the analog nature modulating signals. However, fiber based wireless schemes provi...

With the advent of spectrally efficient wireless communication systems employing modulation schemes with varying amplitude of the communication signal, linearization techniques for nonlinear microwave power amplifiers (PAs) have gained significant interest. In this article, a low complexity, direct-learning multilevel lookup table based adaptive digital predistortion technique has been proposed...

The paper presents our experimental workplace currently built-up for testing of power amplifier linearization algorithms. After a brief introduction into linearization techniques using predistortion, a measurement configuration together with a brief description of its individual components are presented. The paper also presents the first experimental results. On the example of the QPSK modulati...