Extraction of a Multi-Dimensional Polynomial Device Model for an Improved Distortion Contribution Analysis Technique
Aikio, J A
; Rahkonen, T. R.
;
Pedro, J. C.
IEEE Transactions on Microwave Theory and Techniques Vol. 63, Nº 1, pp. 155 - 164, January, 2015.
ISSN (print): 0018-9480
ISSN (online): 1557-9670
Scimago Journal Ranking: 1,01 (in 2015)
Digital Object Identifier: 10.1109/TMTT.2014.2367530
Abstract
This paper presents a method to characterize a multidimensional
polynomial current and charge source models needed
for a distortion contribution analysis technique that can identify
the dominant nonlinearities and different mixing mechanisms. A
separate model characterization step with carefully chosen test signals
is used to break the inherent input–output correlation that
otherwise complicates the model fitting. The proposed Volterraon-
top-of-harmonic-balance technique and improved polynomial
fitting are then verified through the analysis of a 100-W LDMOS
RF Doherty amplifier, which showed that, in this circuit, the cubic
nonlinearity of the gate capacitance is the main culprit of AM–PM
distortion.
