Linealització d'un amplificador de potència pseudo-Doherty LMBA mitjançant models polinomials

Abstract

Today, wireless communications play a crucial role in the telecommunications sector due to the emergence of new technologies such as 5G and smart cities. The amount of data to be transmitted is high, leading to an increased need for bandwidth. One of the key components in these wireless communications is Power Amplifiers (PA), as they amplify the signal to ensure it reaches the receiver correctly. However, a significant challenge with these elements is the high energy consumption they entail. To maximize the efficiency of amplifiers, efforts are made to operate them as efficiently as possible. This involves operating the amplifier in a non-linear region, causing signal distortion. Various solutions exist for balancing efficiency and linearity, with the most prevalent solution being the Digital Predistortion (DPD) technique, which is the focus of this study. The Digital Predistortion technique models the amplifier's behavior to linearize it. Different mathematical models, such as Memory Polynomial (MP), Generalized Memory Polynomial (GMP), and Decomposed Vector Rotation (DVR), have been studied for this purpose. Attempts have been made to combine these models to achieve better results. The DOMP reduction technique, simplifying the number of coefficients in each model, has also been explored. An analysis of the results obtained using these models has been conducted, considering various parameters and the number of coefficients. MATLAB has been used as the programming environment. Subsequently, the best models have been tested using a real digital predistortion environment, meeting expectations by complying with 3GPP standards.