Title :
A highly integrated CMOS direct digital RF quadrature modulator
Author :
Zhou, Yijun ; Yuan, Jiren
Author_Institution :
Dept. of Electrosci., Lund Univ., Sweden
Abstract :
A highly integrated CMOS direct digital RF quadrature modulator, consisting of two 10-bit linear interpolation current steering digital-to-analog converters (DACs) and two Gilbert cell based mixers, is described. By employing linear interpolation, the attenuation of the DAC´s image components is significantly increased, and the reconstruction filter is therefore eliminated. The DAC´s differential current signals are directly sent to the mixer, which improves the linearity of the modulated RF signal. Measurement results on operations of 16 QAM and GSM are presented. This structure is suitable for system-on-chip (SOC) design.
Keywords :
analogue-digital conversion; mixers (circuits); modulators; quadrature amplitude modulation; radiofrequency integrated circuits; system-on-chip; CMOS; Gilbert cell based mixers; SOC design; differential current signals; digital-to-analog converters; direct digital RF quadrature modulator; linear interpolation; modulated RF signal; reconstruction filter; Attenuation; Digital modulation; Digital-analog conversion; Image reconstruction; Interpolation; Linearity; Nonlinear filters; Quadrature amplitude modulation; RF signals; Radio frequency;
Conference_Titel :
Solid-State Circuits Conference, 2003. ESSCIRC '03. Proceedings of the 29th European
Conference_Location :
Estoril, Portugal
Print_ISBN :
0-7803-7995-0
DOI :
10.1109/ESSCIRC.2003.1257200
