A. Behravan
Department of Signals and Systems, Chalmers University of Technology, Sweden
T. Eriksson
Department of Signals and Systems, Chalmers University of Technology, Sweden
A. Svensson
Department of Signals and Systems, Chalmers University of Technology, Sweden
H. Zirath
Department of Microtechnology and Nanoscience, Chalmers University of Technology, Sweden
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Ingår i: GigaHertz 2003. Proceedings from the Seventh Symposium
Linköping Electronic Conference Proceedings 8:5, s.
Publicerad: 2003-11-06
ISBN:
ISSN: 1650-3686 (tryckt), 1650-3740 (online)
In this paper we present and compare several models of compensating the nonlinearity of the RF front-end of a wireless system. The baseband compensation techniques have gained more attentions due to the simplicity of DSP implementation and also utilizing adaptive algorithms. Two baseband compensation techniques; namely predistortion and postdistortion (equalization) of the baseband signal are discussed and teh problems associated with each one is addressed. Furthermore a combination of a predistorter and a nonlinear equalizer is studied. It is shown that under realistic conditions with a frequently saturated amplifier and ISI channel; the latter methods is able to compensate the nonlinearity up to a good extent; while the first two methods can only operate under certain channel conditions and nonlinearity type.
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