Title :
A Metric for the Quantification of Memory Effects in Power Amplifiers
Author :
Martins, João Paulo ; Cabral, Pedro Miguel ; Carvalho, Nuno Borges ; Pedro, José Carlos
Author_Institution :
Instituto de Telecomunicacoes, Aveiro Univ.
Abstract :
This paper presents a quantitative metric for memory effects in power amplifiers (PAs) and applies it to various active device technologies and wireless system contexts. The proposed metric is mathematically founded in the dynamic two-tone distortion response, has a clear physical meaning in the important field of PA linearization and can be easily evaluated from either harmonic balance simulations or measurement data gathered in a microwave laboratory. In addition, a memoryless PA linearizer, optimum for reducing the integrated intermodulation distortion (IMD) power in the operation bandwidth for a two-tone excitation, is derived, providing a rigorous figure-of-merit of PA linearizability under static IMD compensation. The application of this figure-of-merit is then illustrated for three different PA prototypes based on Si LDMOS, InGaP/GaAs heterojunction bipolar transistors, and GaN high electron-mobility transistors, designed for 900-MHz (global system for mobile communications), 2.1-GHz (wideband code division multiple access), and 3.5-GHz (WiMax) wireless systems, respectively
Keywords :
MOSFET; UHF bipolar transistors; UHF field effect transistors; UHF power amplifiers; WiMax; cellular radio; code division multiple access; heterojunction bipolar transistors; high electron mobility transistors; intermodulation distortion; linearisation techniques; microwave bipolar transistors; microwave field effect transistors; microwave power amplifiers; 2.1 GHz; 3.5 GHz; 900 MHz; GaN; InGaP-GaAs; LDMOS; PA linearizability; Si; WiMax wireless systems; active device technologies; figure-of-merit; global system for mobile communications; heterojunction bipolar transistors; high electron-mobility transistors; integrated intermodulation distortion; long-term memory; memory effects; nonlinear systems; power amplifiers; quantitative metric; two-tone distortion response; wideband code division multiple access; Bandwidth; Distortion measurement; Gallium arsenide; Harmonic distortion; Intermodulation distortion; Laboratories; Microwave devices; Microwave measurements; Power amplifiers; Prototypes; Long-term memory; memory effects (MEs); nonlinear systems; power amplifiers (PAs);
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
DOI :
10.1109/TMTT.2006.882871
