無線通訊射頻功率放大器的線性化技術-LINC

The Linearization Technique of RF Power Amplifier for Wireless Communications-LINC

陳勝彥(Sheng-Yen Chen)

指導教授 ： 黃天偉

國立臺灣大學/電機資訊學院/電信工程學研究所/碩士(2006年)

https://doi.org/10.6342/NTU.2006.01930

摘要

在現代化的無線通訊系統中功率放大器扮演一個重要的腳色，它往往是最消耗功率的元件。在無線發射器中，因為功率放大器的非線性特性，要設計高效率且高線性度的系統是相當困難的挑戰。於是功率放大器的線性化以及提高效率的技術被採用來改善發射器的線性度和效率。
LINC技術是眾多的功率放大器線性化和提高效率的技術之一。採用LINC技術，有高效率的非線性功率放大器能夠被使用，且能將時變振幅的調變訊號線性地放大。因此，採用LINC技術的發射器能夠同時達到高線性度且高效率的效果。
本篇論文中，我們說明LINC發射器的操作原理以及討論在LINC發射器中線性度和效率非理想的效應。我們也使用模擬以及實作量測去驗證當時變振福的調變訊號被發送時，LINC發射器可以在線性度和效率上優於單一個A類線性功率放大器。採用LINC技術的發射器包含了一個信號分離器,兩個功率放大器,以及一個功率合成器。在進行LINC發射器的實驗中，我們使用兩台向量訊號產生器去產生LINC調變的訊號取代了信號分離器的功能；並且搭配實作的功率放大器以及功率合成器來進行量測。我們設計一連串的實驗去逐步執行。我們將實作的幾種功率放大器以及功率合成器分別運用在LINC發射器中組合成各種LINC系統，並且觀察各種LINC發射器的線性度和效率的變化。

關鍵字

功率放大器 ； 線性化技術 ； LINC

並列摘要

The power amplifier plays an important role in a modern wireless communication system and is the most power-hungry device. Because of nonlinear characteristic of power amplifier, it is a big challenge to design a high linearity and power efficiency in a wireless transmitter. Linearization and efficiency enhancement techniques of power amplifier can be adopted to improve the linearity and power efficiency of the transmitter.
LINC (Linear Amplification using Nonlinear Components) technique is one of power amplifier’s linearization and efficiency enhancement methods. By adopting LINC technique, nonlinear power amplifier with high power efficiency can be used and the input variable envelope signal can be amplified linearly by a LINC transmitter. Thus, high linearity and power efficiency can be achieved in LINC transmitter.
In this thesis, we describe the operation of LINC system and discuss the nonideal effects on linearity and power efficiency. We use simulation and measurement to verify the LINC transmitter superior to a single Class-A power amplifier on both linearity and efficiency when a variable envelope modulated signal is used. The LINC transmitter contains a signal separator (SCS), two power amplifiers, and a combiner. In measurement, we use two vector signal generator to generate LINC signals in place of SCS, and power amplifiers and combiners are implemented. A series of experiments are carried out step by step. Several power amplifiers and combiners are used in the measurement of LINC transmitter, observing the variations of linearity and power efficiency of these systems.

並列關鍵字

Power Amplifier ； Linearization Technique ； LINC

參考文獻

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