ADAPTIVE CONTROL OF POWER AMPLIFIER LINEARIZATION TECHNIQUES BY USING HYBRID ANALOG AND DIGITAL APPROACHES

2021-9
Abdulwahab, Bassam
Power Amplifiers (PA) are widely used in mobile communication systems, yet power amplifiers have a non-linear region which is the major problem in all communication and radar systems. Moreover, PAs show a low power efficiency when operating in their linear region and are highly non-linear when operating in their high-efficiency region. To overcome such issues, there are different methods to linearize PAs and other methods to enhance their power efficiency. These linearization methods are built to meet a certain linearity level for a specific application. However, the linearization techniques are not built to cope with the changes that might occur to the system. In this thesis an adaptive control mechanism for linearization techniques is studied, the goal is to achieve a linearization system for the PA that can maintain the desired linearity level without compromising the efficiency. The idea of the system is to find an intelligent way that can be added to any linearization technique to detect and measure any changes in the system and the effect of this change on the system, then adapt the system to overcome this change and achieve linearity. A digitally programmable feedback control system will be added to the PA linearization technique, having a microcontroller in a feedback vi circuitry that will work as an efficient detector to detect any changes on the sampled signal with accuracy as to control an adaptive network. Accordingly, the microcontroller will decide the voltage control changes required to maintain the required linearity.

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Citation Formats
B. Abdulwahab, “ADAPTIVE CONTROL OF POWER AMPLIFIER LINEARIZATION TECHNIQUES BY USING HYBRID ANALOG AND DIGITAL APPROACHES,” M.S. - Master of Science, Middle East Technical University, 2021.