Title :
AM-PM distortion caused by transistor´s signal-dependent input impedance
Author :
Rahkonen, Timo ; Hietakangas, Simo ; Aikio, Janne
Author_Institution :
Eletronics Lab., Univ. of Oulu & Infotech Oulu, Oulu, Finland
Abstract :
AM-PM distortion causes spectral regrowth in RF transmitters with modulated signals. One reason for AM-PM is the fact that signal-dependent transistor input capacitance pulls the frequency response of the input matching network and causes phase shift already at the input of the transistor. This paper studies the Miller capacitance effect in most common fixed-supply and supply modulated power amplifier topologies and typical matching networks, and shows that the signal-dependent input capacitance can cause significant AM-PM distortion.
Keywords :
distortion; impedance matching; power amplifiers; transistors; AM-PM distortion; Miller capacitance effect; RF transmitters; fixed- supply; frequency response; matching networks; phase shift; power amplifier topologies; signal-dependent transistor input capacitance; transistor signal-dependent input impedance; Capacitance; Impedance; Impedance matching; Logic gates; Mathematical model; Power amplifiers; Transistors; AM-PM; Miller effect; input capacitance; input matching;
Conference_Titel :
Circuit Theory and Design (ECCTD), 2011 20th European Conference on
Conference_Location :
Linkoping
Print_ISBN :
978-1-4577-0617-2
Electronic_ISBN :
978-1-4577-0616-5
DOI :
10.1109/ECCTD.2011.6043830
